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Prefabrication for affordable housing

State-of-art report prepared by Task Group 6.7

August 2011


Subject to priorities defined by the Technical Council and the Presidium, the results of fib’s work in Commissions and Task Groups are published in a continuously numbered series of technical publications called 'Bulletins'. The following categories are used:

category minimum approval procedure required prior to publication Technical Report approved by a Task Group and the Chairpersons of the Commission State-of-Art Report approved by a Commission Manual, Guide (to good practice) or Recommendation

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Any publication not having met the above requirements will be clearly identified as preliminary draft.

This Bulletin N° 60 was approved as an fib state-of-art report by Commission 6 in October 2010.

This report was drafted by fib Task Group 6.7, Affordable housing: David Fernández-Ordóñez (Prefabricados Castelo, Spain, Convener), Antoni Cladera Bohigas (Univ. Of Balearic Islands, Spain), Barry Crisp (Crisp Consultants, Australia), Bruno Della Bella (Gruppo Centro Nord, Italy), Iria Doniak (ABCIC, Brazil), Jaime Fernández Gómez (Intemac, Spain), Holger Karutz (CPI, Germany), Diane Laliberte (BPDL Precast Concrete International, Canada), Marco Menegotto (Italy), Julian Salas (Ministerio de Ciencia y Tecnologia, Spain), Javier Angel Ramírez (Univ. Politecnica de Madrid, Spain), Spyros Tsoukantas (Greece) Corresponding Members: Cliff Billington (J&P Building Systems, UK), Andrzej Cholewicki (Building Research Institute, Poland), Thomas D´Arcy (The Consulting Engineers Group, USA), Paulo E. Fonseca de Campos (Brasil), Antonello Gasperi (Italy), Ravindra Gettu (Indian Institute of Technology Madras, India), Subbaiya Kanappan (Larsen & Toubro, India), Luciano Marcaccioli (Officine Piccini, Italy), Pablo Moñino (Prefabricados Castelo, Spain), Shirish Patel (Shirish Patel & Associates, India), José Adolfo Peña (OTIP, Venezuela), Sthaladipti Saha (Larsen & Toubro, India), Arne Skjelle (Construction Products Association, Norway) Figures in Chapter 5, “Examples of housing systems”, were drafted by. J.A. Ramirez. © fédération internationale du béton (fib), 2011 Although the International Federation for Structural Concrete fib – fédération internationale du béton – does its best to ensure that any information given is accurate, no liability or responsibility of any kind (including liability for negligence) is accepted in this respect by the organisation, its members, servants or agents. All rights reserved. No part of this publication may be reproduced, modified, translated, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission. First published in 2011 by the International Federation for Structural Concrete (fib) Postal address: Case Postale 88, CH-1015 Lausanne, Switzerland Street address: Federal Institute of Technology Lausanne – EPFL, Section Génie Civil Tel +41 21 693 2747 • Fax +41 21 693 6245 [email protected] • www.fib-international.org ISSN 1562-3610 ISBN 978-2-88394-100-7

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fib Bulletin 60: Prefabrication for affordable housing iii

Foreword The need for housing has increased significantly during the last decades all over the world. It is felt particularly in countries where the population growth rate is high and the economy is developing fast; but everywhere people are shifting from country land to towns, where housing in neighbourhoods often becomes critical. Apart from problems of adaptation of people to different lifestyle and of urban planning, a difficulty may rise even in meeting the demand for buildings. Also, the necessity for a great production of houses in a limited time appears, when reconstruction urges after disasters or renewals for inadequacy, together with updated quality requirements. Large projects always face cost and time constraints. Local conditions may be rather variable, with respect to physical, social and market environments. Thus, minimising cost and time of construction, while maximising quantity and quality of product, may lead to different solutions. The concept of “affordable”, meaning compatibility of demand and means, is well understood as such everywhere, although its practical application may be much different from place to place. Prefabrication, with its adaptability and quality consciousness, may offer valid, speedy, cost efficient and sustainable solutions in these instances. fib Commission 6, Prefabrication, is well aware of this and had the idea of sharing information on this issue, which materialised in 2003 when a very successful workshop was held in Chennai, India. The contribution of experts from many countries gave rise to quite interesting mutual information and comparisons. Then, Task Group 6.7 was started, with the aim of collecting the experience from around the world on affordable housing built with precast structural concrete. Its work is concluding with this “State-of-art Report”, offering an overview of housing systems as well as information on their features. A document of this kind was not available before; this report is therefore deemed to be of great interest and a source of ideas for all those who have to confront similar problems. Commission 6 is very grateful for this result to David Fernàndez Ordòñez, who has led the Task Group with determination, up to this successful accomplishment. Marco Menegotto Chairman of fib Commission 6, Prefabrication


iv fib Bulletin 60: Prefabrication for affordable housing

Contents Foreword iii

1 Introduction 1

2 Scope 3

3 Historical review 3

4 General features 5

4.1 Requirements for housing 6

4.2 Materials 8 4.2.1 Precast concrete / concrete 8 4.2.2 Ferrocement 9 4.2.3 Autoclaved aerated concrete 9 4.2.4 Wood 9 4.2.5 Steel 9 4.2.6 Polystyrene 10 4.2.7 Plaster 10 4.2.8 Mortar/grout 10 4.2.9 Fly ash 10 4.2.10 Soil / Soil-cement mixture 10 4.2.11 Composites 10

4.3 Precast structural systems 11 4.3.1 General 11 4.3.2 Structural systems 12 4.3.3 Selection of a structural precast system 12 4.3.4 Frame systems 14 4.3.5 Wall systems 22 4.3.6 Floor systems 29 4.3.7 Stairs 34

4.4 Production, transportation and erection process 36 4.4.1 Production 36 4.4.2 Transportation 46 4.4.3 Erection 38

4.5 Waterproofing and insulation 38

4.6 Services and installations 40

5 Examples of housing systems 41

6 Bibliography 121


fib Bulletin 60: Prefabrication for affordable housing 1

1 Introduction

There is a great need for housing in the world. This need has increased significantly during the last decades due to the fact that the greatest population growth has occurred in the outskirts of cities in developing countries, where the distribution of wealth is increasingly polarized. There is a large amount of human capital but a lack of technology and knowledge, as well as training for designers, contractors and other specialists in the construction industry. In addition, financing and the cost of land is a great problem for the construction of houses around the world.

UNESCO states that the right to housing, the right to shelter for individuals and families, is

a condition of citizenship. Also Human Rights Watch states that every person has a right to an adequate level of living, and that housing is within this right.

In developing countries there is a need for shelter that can guarantee safety against extreme

natural or climatic conditions, but these affordable shelters have also to comply with other needs like waterproofing, insulation and installations or sanitation facilities. These needs vary strongly from one part of the world to other. Also financing, road networks, water supply and infrastructure vary from one part of the world to others.

In developed industrialized countries, housing is normally considered a product. In

developing countries housing becomes a process in which the owner is often also the builder. This process starts with land reclaiming and can last five to fifteen years. Many times people live in a house that is not finished but in a continuous process of building. In this construction process there is collaboration between different agents like administration, co-operative organizations and builders.

With industrialization and prefabrication it is intended to build mass production elements

or to optimise the design of materials for building construction. There is much experience in the industrialization of construction systems around the world, but it is unknown to other parts, and many times even to neighbouring areas. We must understand industrialization as the result of applying technologies either to production (process technology) or to the product (product technology).

It is of primary importance to take into account the construction possibilities in a given

area. This means that production equipment, erection equipment – like mechanic or manual cranes and transportation, both trucks and mobile elements, and infrastructures such as roads – are different in each area. These differences impose the available solutions for each area.

Also the economics of the solution change from area to area because in developing

countries costs are different from those in developed countries. In many cases the cost of materials, equipment and technology is higher in developing countries but the cost of manpower is lower. Therefore in many occasions it is necessary to look for straightforward technology and elements of a size that can be produced, moved and erected by manpower.

The technology adopted for housing components should be such that the production and

erection technology can be adjusted to suit the level of skills and handling facilities available under metropolitan, urban and rural conditions. The structural systems and components selected should ensure minimum use of materials with maximum structural advantage.


2 1 Introduction

Industrialization is interesting as a way to achieve harmony between construction and industry. The technology of developed countries can be applied to the local possibilities of developing countries. Production procedures exist in the industry but they have to be adapted to the specificity of each area. Specific parts added to industrial components will form the industrialized autonomous system.

Housing can be considered both as a whole and as a combination of functional elements.

Affordability of housing is not simply a matter of more economical construction technologies. What dominates the total cost is more often the price of land, or of services, and what finally determines affordability is long-term financing of housing and whether it can be made available to the income groups that are expected to move into the housing.

The methodology for affordable housing therefore has to be less sophisticated, involving

less capital investment. There are four key challenges to be overcome in the shortage of affordable housing facing

developing countries, namely: lack of resources, insufficient funds, shortage of skills, and time constraints. The construction industry needs to make greater use of prefabrication in undertaking projects in order to overcome the shortage of specialized manpower.

There are several levels of industrialization, from closed industrial systems to a partial use

of industrial components or open systems that allow a large freedom of design and construction.

There are two directions of technological transfer: vertically, from theory to practice; and

horizontally, from one industry segment to another. The following principles were put forward by J. Salas at the United Nations Conference on

Human Settlements (“Habitat I”), held in 1976 in Vancouver, Canada:

• The simple adaptation of western ideas for materials or processes does not in general support housing solutions for low-income parts of society.

• It is of vital importance to use designs that are appropriate to the economic, social, cultural and natural conditions of each community.

• It is of primary importance to stop the outflow of currency to purchase machinery and raw material for local production.

• Standards and rules coming directly from developed world make housing unavailable in third world and developing countries.

Concrete is a material with a lot of advantages to be used in affordable housing: it is

durable, as it needs little maintenance, has good thermal inertia, can be used both as structural and finishing material, and is not sensitive to organic attack. It also has some disadvantages, such as higher cost in developing countries compared to developed countries, and also a possible lack of materials, mainly cement or admixtures.

Today recognizing diversity is a primary need for developing processes in the industry of

production and erection of elements for construction.



2 Scope The concept of “affordable” or “low-cost” housing can take on rather different meanings.

Although globalization affects the way of life of all people in some way, economic social and functional requirements of goods are so different around the world that useful low-cost items in one context may be easily unaffordable or unsuitable in other ones.

However, given a particular context, the concept has a clear meaning and it is well

understood. Housing is a primary need of humans. Building houses is an important activity everywhere and controlling its overall cost appears to be a major issue in any context.

The need for houses at a more or less low cost – and in the shortest amount of time, which

also saves costs – may concern high-rate urbanization, rural areas to be upgraded, workers’ settlements in remote regions, rebuilding dwellings destroyed by disasters such as earthquakes, floods or wars, and up to holiday resorts and leisure dwellings.

Prefabrication of structural concrete has become so versatile that it can offer valid

solutions in any situation and at any scale, ranging from simple houses to sophisticated architectures, and provides products ranging from elements for self-construction up to large turn-the-key projects that require significant investments and heavy equipment; always for an “affordable” cost, relatively speaking, and practically without alternatives.

The scope of this State of Art Report is to provide an overview of what is being done and

can be done by prefabrication in the field of housing, under the most varied conditions. By showing the main features of a number of construction systems, although not entering

into the details of the solutions, it aims to make possible a comprehensive comparison, which should help in learning, exchanging and developing ideas on how to better meet the housing needs everywhere, at sustainable cost.

3 Historical review

Prefabrication, intended as fabrication of large units to be subsequently assembled into a structure, dates back in prehistory. In the early 19th century, the industrial revolution had an immeasurable influence on architecture and prefabrication. All design was affected by the common use of new materials such as steel and glass. Design changes were fundamental in some cases and gave rise to new styles that were solidly based on the concept of industry.

The post World War I era in Europe saw a major increase in the industrialization of

building. Due to the destruction of existing buildings and the lack of new construction during the intra-war years, there was an acute demand for economical and simple building systems.

World War II concluded with another housing crisis both in the United States and Europe.

Though United States territories had not seen any action, there was a need for housing due to the number of returning soldiers who quickly started families. A population explosion accompanied the end of the war. Once again, prefabrication was used to meet the demand for housing. This was the time when industrial prefabrication of structural concrete developed and expanded to take a prominent part into the construction market.


4 3 Historical review

Prefabrication is one of the ways to industrialize the construction process, but not the only one. Prefabrication with large panels and closed systems is not much used at present, even if it took a large part on the development of housing after World War II.

We can distinguish three main periods in the evolution of prefabrication for housing during

the second half of the 20th century: 1950-1970: massiveness, euphoria and business. Closed systems based on large panels

were dominant in the East Europe, and also very important in today’s European Community countries. These systems imposed rigid constraints because of the economy, speed of construction and limitations to architecture.

The constraints were:

• need for minimum of several thousands of housing units grouped together; • very rigid projects, with very little formal variations to minimize the different

elements; • blocks of units set in a linear way as long as possible so there was no need to change

crane tracks; • minimum spans and heights to comply with transportation; deck slabs of room size; • little or no flexibility for the redistribution in plan due to the use of massive panels,

even non-load-bearing, so most could be built in the factory. Industrialization was, for the designer, a matter of economy of construction and the system

was a strong constraint to architecture. To change any parameter of the system would imply losing competitively in the market. Camus said once when asked about thermal bridges: “I sell too much, I do not have time to improve”.

1970-1985: crisis and confusion. Prefabrication with large elements tried to get out of the

maze in which it was trapped, by providing more flexibility and variation in its products. The market changed in the EU from demand-led to offer-led. Then quality became the key point. Some panel systems changed, offering variety and quality with good response to small demands; others looked for ways to export, and many disappeared.

The basis for what was called “open prefabrication” was set, with several compatible

components. Technology applied to component production adapted very well to the crisis, and even with

higher costs they could be more easily adapted to smaller and different works. Also components could adapt very easily to the new growing market of individual and low-rise housing in Europe.

A dramatic reduction in the size of construction works penalized closed concrete systems

and favoured component construction. Also components could be easily adapted to new and fast normative changes.

Since 1985: other concepts in prefabrication, subtle prefabrication. Most elements in

housing are now component construction. Large element construction has practically disappeared

New prefabrication techniques and new designers get involved in small and large projects

with excellent results. Now different kinds of individual elements are built using the highest



possible amount of automation to adapt to more and more individualized demands. The use of modern industrialization concepts that are common in the automotive industry is more and more common in the prefabrication of housing.

It is of the highest importance to use all the experience of the last century in Europe to develop new ways of construction for affordable housing in all parts of the world.

4 General features

The right to housing, the right to shelter for individuals and families, is a condition of citizenship. However to define the requirements for shelter are different, depending on many diverse aspects like geographical situation, climate, seismic risk, economy, and social.

The aim is to design and build a shelter that is consistent with the income of the future

users. Regarding this aspect, evolutive systems that allow growth from very simple constructions are especially interesting.

Housing is a basic need and like any basic human need will be constantly in demand. The

concept of liveability of a house is usually framed in terms of activities in a house. The human requirements for space differ widely depending upon the geographic location and the climatic conditions of the site and upon the socio-economic and cultural standards of the population.

Certain principles – like planning a good environment with adequate light and air,

orientation, protection against noise, dust and local hazards – must be observed and minimum specifications must be followed without violating code rules for foundations, superstructure, plastering, painting, doors, windows and roofs.

Standardisation, modular co-ordination and typification of building design are essential.

Rationalisation of the dimensions of building components and the finished structure has a major influence on the planning of buildings. This results in optimum use of space, increased productivity and efficient use of building materials. Such a rationalisation is achieved by dimensional co-ordination.

Geographical situation, and the climate which goes along with it, is relevant for the needs

in these kinds of buildings. Areas with tropical weather require water tightness before other needs. In these areas special attention has to be applied to connections between structural members and also panels when used. Also the way in which water is removed from the building is relevant.

To meet minimum health standards, certain household services and facilities are required.

These include water supply, sanitary means for the disposal of household wastes including domestic sewage, facilities for washing clothes and cleaning household utensils, for bathing, for storage, preparation, cooking and consumption of food, and for storage and safeguarding of personal property.

Due to the difficulty of air conditioning climate installations, at least in the beginning,

ventilation is a key factor when building affordable housing. Therefore proper windows in the walls, protected by trusses, as well as roof ventilation to create natural ventilation, are relevant.


6 4 General features

In some circumstances the need for permanent housing has to take into account the stability of the structure against animal attack, rot or other biological hazards. In these situations the use of concrete leads to solid structures that resist natural deterioration.

Seismic action is a significant factor when building housing. There have been many

disasters due to the lack of properly constructed houses in areas affected by earthquakes. It is very important to follow some simple construction recommendations when building houses in seismic areas. Some relevant ones are to tie different parts of foundations and walls or structural parts of the structure, so that a local failure does not lead to an absolute ruin, or let the structure have deformations without leading to collapse. Some simple rules can be applied depending the type of structure that is used, e.g. wood, masonry, concrete, precast or in situ, steel or some combination of them. Many times sufficient rigidity is easily obtained in low rise buildings without the need for ductility. Also construction techniques with light materials are interesting in seismic areas because they reduce the seismic forces.

Access to the working site might also be relevant when deciding what system is to be used.

Often transportation and lifting capabilities are defining the length and weight of the elements. Therefore in many cases it is only possible to use elements that can be lifted by two persons.

Housing is a basic necessity as well as, being a vital part of the construction sector, an

important factor in the economy. As such, housing acts as a major contributor to employment and income generation and helps people both directly and indirectly in their socio-economic development. Economy is an aspect that is often limiting for a population to be able even to reach housing. Therefore sometimes the ability to obtain enough available funds is a key factor to start building a house. Another relevant factor is the availability of land. It is no wonder that in many situations, housing starts on land that is not used in any other way and later on is occupied with self-construction of housing. At first this starts without any common works, roads, water, sewers or other infrastructures, which later self-develops as the community does.

There are some kinds of help available to finance affordable housing, some from local

governments, normally for the purchase of building materials. Some non-profit organizations have taken part in specific projects with funding and technical help, which has been very useful locally. Private financing organizations have not taken part except for some recent micro credits activity, which extends quite quickly.

Social aspects are relevant when deciding both the internal and external organization of the

building. Depending on social conventions, there will be, for example, more separated rooms besides kitchen or a community room, or other distribution of internal space, as for example in Indian communities where the bathrooms are not inside the house, and it is considered a relevant characteristic to have a courtyard within the house. Some other cultures tend to organize social life outside the house in social or communitarian buildings. 4.1 Requirements for housing

“Affordable housing” must comply with the same requirements of safety, use, health and energy saving as normal buildings. The codes of different countries deal with this subject, or when no national codes exist, it is possible to use International Standards, taking into account the limitations due to the economical design.



A possible classification of requirements to comply with could be as follows:

• Basic requirements for structural safety, which aim to ensure that the building has an adequate structural behaviour against possible actions during its service life and construction. To comply with these requirements, buildings are to be designed and built according to the applicable standards and codes, and must have the same level of safety as other similar constructions. Any reduction in safety is not allowed due to economic reasons. These requirements are divided in two groups: − strength, stability and robustness to avoid inadmissible risks; − service life capacity for normal use, with regard to deflections, cracking and

vibrations. • Basic requirements for safety in the case of fire, which consist of reducing the risks of user

damage due to an accidental fire. For this purpose it is necessary to comply with the following requirements: − interior propagation – limiting the risk of fire spreading to other places of the same

building; − exterior propagation – limiting the risk of fire spreading outside of the building, − evacuation of users; − possibility to install fire-extinguisher equipment, even with individual kits; − possibility for access and intervention by the fire brigade; − structural strength for a determined period during the fire.

• Basic requirements for safety of use, which implies that the users won’t be hurt as a result

of the characteristics of the design, construction or maintenance. For this purpose the following requirements must be observed: − safety against the risk of falling, due to slippery floors, holes, staircases or level

changes; − safety against the risk of impact, being trapped or imprisoned; − safety against the risk caused by inadequate lighting; − safety against the risk caused by high occupation conditions; − safety against the risk of drowning; − safety against the risk caused by moving vehicles; − safety against the risk caused by the action of rays of sunlight.

• Basic requirements for health and protection, which consist of reducing to acceptable

limits the risk that users, while making normal use of the building and installations, suffer illness or injury. Also the building must not be deteriorated or deteriorate the environment. For this purpose, the following requirements must be fulfilled: − protection against water and dampness; − collection and evacuation of wastes; − quality of interior air; − supply of drinking water; − evacuation of sewage.

• Basic requirements for protection against noise, i.e. to limit inside the building

disturbances created by noise. For this purpose, it is necessary to comply with the relevant acoustic protection limits, for noise produced both inside and outside the building.



• Basic requirements for energy saving. The buildings must also comply with some requirements for the thermal insulation of walls and facades, air permeability and thermal bridges.

The risk of dampness due to condensation must be avoided. Heating installations, where

they exist, must be suitable to give thermal comfort while avoiding energy waste. 4.2 Materials

This chapter provides general background information about various materials that can be used for affordable housing. Restricting ourselves to the attached catalogue of example housing systems, we focus on materials that are used in it.

Looking at construction materials for affordable housing, one can divide their properties

roughly into physical and environmental properties. Physical properties can be structural properties or building physics properties. Interesting environmental properties are durability, wind and weather resistance.

It is necessary to know about both the physical and the environmental properties of the

materials used in order to be able to erect a proper housing structure. Foundations should be made of very durable material. Depending on the location, they

have to be water resistant. The compression strength of foundations necessarily needs to be able to withstand the sum of the loads of the housing structure, including dead load and live load. Although one can erect low cost housings even without a ground floor slab, it is recommendable to take it into account. The ground floor slab should protect the inhabitants from temperature variations, and its compression strength should be high enough to resist the live load.

The walls of the buildings need to have enough compression strength to bear the vertical

loads. In addition, they should protect the inhabitants from wind and rain, and they can also have heat insulation properties. If a structural framework is used, the wall panels need only to fulfil the above-mentioned inhabitant protection requirements.

The floor decks above the ground floor have to carry the loads of the upper level, if any. If

their function is mainly the roofing of the building, they should – besides their structural function – be weatherproof.

Besides the structural properties, further important aspects of the materials to be

considered are thermal insulation and fire resistance. Less important for affordable housing, but to be taken into account for more comfortable housing, are properties like sound insulation, etc. 4.2.1 Precast concrete / concrete

Precast concrete and concrete in general can be used for all kind of structural elements for buildings. The main advantages of concrete for affordable housing are very good compression strength, high durability and fire resistance. Prestressed concrete slabs and hollow core slabs can carry high live loads at a low dead weight. Lightweight concrete increases thermal insulation properties. Fibre reinforcement with polypropylene or steel fibres increases the ductility of the material. Concrete, especially precast concrete, can be used for linear structural elements like beams and columns, for foundations, and for 2D elements like walls



and floors. At least structural concrete elements subject to stresses other than compression should be reinforced with steel.

Concrete blocks can be used to erect solid walls. Mortar/grout is mostly used for the

stacking of concrete blocks. 4.2.2 Ferrocement

Ferrocement a highly versatile form of reinforced concrete made of cement mortar and wire mesh reinforcement. Due to the same components, ferrocement possesses similar strength and serviceability to reinforced concrete. 4.2.3 Autoclaved aerated concrete

Autoclaved aerated concrete (AAC) is a lightweight building material with excellent thermal insulation properties. AAC consists of 80% air and 20% solid material. Raw materials needed for its production are sand, cement and/or lime as binders, and water. To create the pore structure of AAC, small quantities of aluminium are used. The production process of AAC is highly automated using autoclaves.

AAC provides good compressive strength even though the specific weight of AAC is

relatively low. Fire protection is similar to concrete. AAC is available as reinforced AAC, as well, providing better bending strength than without reinforcement.

AAC is available in the form of blocks, which are very suitable for self-construction, and

of large wall panels for automated construction processes. 4.2.4 Wood

Wood is mainly used for linear structural elements/structural framework, suitable for compression, tension and bending forces. Load bearing floors can be realized with wooden beams, but mostly this construction requires additional topping with planks. Wooden planks can also be used for the ground floor when there is no danger of water/moisture. Due to the low dead weight, walls and floors made of wooden planks are easy to erect.

Wood is an orthotropic material, as its properties are dependent on the direction. One has

to differentiate between loading in parallel and orthogonal to the fibres of the wood. Without protection, wood has low fire resistance, and also low durability in comparison to concrete. 4.2.5 Steel

Load bearing steel structures are not included in the attached catalogue. Thin steel plates can be used to protect the outer walls of the buildings, since they are weatherproof. They can of course also be used for the roof closure. Steel generally has to be protected to avoid corrosion. With suitable coatings, steel can be very durable, fire resistant and weatherproof.

Thermal and sound insulation properties are not particularly good, compared with

concrete, for example. 4.2.6 Polystyrene

Polystyrene cannot be used as load bearing material, but the thermal insulation properties are very good compared with other materials mentioned. If possible, one should combine a



load bearing structure, heat insulation consisting of polystyrene and a weatherproof outer layer. 4.2.7 Plaster

Plaster can be used to provide outer walls with weather resistance. This might be necessary in case the walls were not erected with proper materials, having many joints in between. Plaster can help to close these joints, and can of course be used for decorative needs as well. 4.2.8 Mortar/grout

Mortar/grout is necessary to glue concrete blocks, especially for walls, together. It should not be taken into account as load bearing material itself. It needs to be combined with suitable blocks for wall structures. Another possibility is to use grout to close vertical joints. 4.2.9 Fly ash blocks

Fly ash blocks consist of around 90% fly ash, 5% lime and 5% gypsum, as well. With an acceptable compression strength, fly ash blocks provide good insulation properties at a low dead weight. 4.2.10 Soil / soil-cement mixture

Some systems of the attached catalogue propose the use of soil, or soil-cement mixture as load bearing material. Although this is possible in principle, one has to take into account that the physical properties of this material are not as constant as those of other materials. Blocks made of soil-cement mixture might be used for wall structures with low demands. To protect these walls from weather influences, they should be coated, e.g. with plaster.

Table 4.2-1: Material properties

Properties Density [kg/m³]

Young’s modulus [N/mm²]

Compressive strength [N/mm²]

Tensile strength [N/mm²]

Thermal conductivity λ [W/mK]

Concrete 2.400 25.800-45.200 12-100 1.6-5.2 2.3 Lightweight concrete

400-2.000 850-32.000 12-60 0.8-4.1 0.13-1.6

Autoclaved aerated concrete

300-1.000 1.200-2.500 2.5−10 0.25−1.0 0.09

Wood 500-1.000 E┴ = 250-1200 E║ = 8000-17000

σ┴ = 2-8 σ║ = 6-20

σ┴ = 0 σ║ = 4-15

0.09-0.24

Steel 7.800 210.000 240 240 50 Polystyrene 15-30 1-11 0.01-0.07 0.2-0.5 0.03-0.04 Plaster 700-1.800 1.000-5.000 2-5 0.3-0.5 0.25-1.0 Mortar/grout 700-2.000 5.000-35.000 1-50 1-5 0.21-1.6 Fly ash blocks 1.000-1.400 – 5-6 – 1.2-1.6 Soil 1.400-2.200 0.5-50 1-2 0 1.5-2.0

4.2.11 Composites

Fibre reinforced plastics (FRP) laminates: FRP are used for the manufacture of prefabricated, portable and modular buildings as well as for exterior cladding panels that can simulate masonry or stone. Typical application items are doors, as well, that might be insulated in between two layers of FRP.



Fibre reinforced cements: FRC are used mainly for exterior cladding panels, that can also simulate other materials. Typical is glass-fiber reinforced cement (GFRC).

Natural fibre composites: Reinforcement fibres made of jute, sisal, coconut fibre, banana fibre, etc., are cheap and their use does not affect the environment. They can be used as for reinforcement for prefabricated products that need low bending capacity, e.g. roof tiles or others.

4.3 Precast structural systems

4.3.1 General As mentioned in previous chapters, when speaking about “affordable housing”, it is of primary importance to take into account the available technological level and construction possibilities in the given area. Also the economic level of each country or area of the country should not be neglected, since it might be (and this is generally the rule)in developing countries) that the cost of materials, equipment and technology is much higher than manpower. Speaking now about reinforced concrete prefabrication, production and erection equipments (cranes, etc.) as well as suitable infrastructure (roads, etc.) and transportation means (tracks, etc.) are needed. Thus it might be that, to achieve affordable housing, full reinforced concrete prefabrication is not the best solution everywhere. Nevertheless, structures made with precast concrete have many advantages, such as strength in both static and dynamic loading, good response to strong winds or earthquake actions, durability, fire resistance, low sensitivity to organic attack, good thermal inertia, etc. Also it should be kept in mind that prefabrication based on reinforced concrete offers a lot of advantages for affordable housing, such as speed of erection, simplicity according to demand, and waterproofing. Generally speaking it has suitable quality, including all that cannot always be provided without the high level of industrialization of prefabrication. Affordable housing is in most cases also based on simplicity. In this respect, buildings with simple layouts, e.g. buildings with orthogonal plans, are ideal for precasting because they exhibit a degree of regularity and repetition in their structural grid, spans, and member size that lead inevitably to economical solutions. In what follows an attempt is made to present briefly the main features of representative precast reinforced concrete structural systems, as well as the main principles of their behaviour under static and dynamic loading. Intentionally, no formulas are presented in this chapter, since it is a matter of specific design. 4.3.2 Structural systems

A large number of technical solutions and systems may be identified in the precast industry for reinforced concrete precast buildings. Nevertheless, they all belong to a rather limited number of basic structural systems, of which the design principles are more or less identical.



By structural system, we mean a proper arrangement of vertical and horizontal bearing members, suitably connected between them to be capable to resist any kind of vertical and lateral loads.

Depending on the type of bearing elements that constitute such a structural system, we may

distinguish systems made by: i) linear elements (columns – beams), ii) walls, iii) combination of linear and wall elements, iv) cells (precast monolithic room cell systems). The above (i-iii) structural systems are completed with a number of complementary precast

elements for the realization of floors, roof, staircases and facades.

4.3.3 Selection of a structural precast system

Although a lot of “closed” different precast systems are found in the precast market, the choice of a specific structural system depends mainly on the use of the building, the soil conditions, the seismicity and the technological level of the area.

Frame systems are the most common type of precast systems and are found everywhere around the world, since they permit a high degree of flexibility for the function of the final building, and also give a high degree of freedom to the architect.

Multi-storey frame systems are mainly used for apartment buildings, commercial buildings, offices, car parks, etc. For these structures, particular attention should be paid to the selection of the type of frame system – hinged (Fig. 4.3-1a,b) or moment resisting (Fig. 4.3-1c) – and its lateral stability needs. Normally moment resisting frame systems are not used on affordable housing buildings due to the complexity of ensuring “emulative behaviour”.

Single-storey frame systems are normally industrial buildings or warehouses. These types of buildings, see Fig. 4.3-2, are characterized by their large degree of repetition and large spans (say up to 30 m or more). The frame normally comprises two (or more) columns with moment fixed connections at the foundation and free supported mostly sloped prestressed roof beams. The distance between portal frames is governed by the span of the roof beam, on which roof elements are directly supported. They are normally not included in the catalogue of precast affordable housing systems but their concepts and design features can be used within more simplified systems in affordable housing.

Wall systems, see Fig. 4.3-15, are mostly used for apartment buildings but also for individual housing or for prisons, hotels or bungalow construction. The surface of the elements is mostly smooth on both sides and ready for painting or wallpapering. In some cases in wall systems most of the walls are load bearing in one or the other direction, depending on the height of the building and the seismicity of the area. Nevertheless, the trend is to arrange load-bearing walls only in one direction of the building and to use light partition walls in the other, which is much recommended for non-seismic areas or for areas of low seismicity.

There are sophisticated systems for housing or office buildings not suitable for affordable housing but other more simple systems are frequently used in affordable housing due that the precast panels are used both for structural and for façade or interior partition purposes.



a)

b)

c)

Fig. 4.3-1: Hinged frame system: a) structural scheme, and (b) sketch of the arrangement of the members [41a] c) Structural scheme of a moment resisting frame system [37]

Fig. 4.3-2 Typical single storey industrial building

Monolithic room cell systems are sometimes used for individual housing, with a proper arrangement one after and/or above the other, but also they may be used for parts of buildings, e.g. for bathrooms, kitchen blocks, garage boxes, etc. The main advantage of such systems lies in the speed of construction and the industrialization of manufacture since the



finishing and equipment of the cells can be completely done at the precasting plant. Nevertheless transport problems and lack of flexibility in the layout of the project should be taken into account when using room cell systems. They have been widely used in closed systems for large amounts of houses to be erected in a very short time.

All systems depend, for the distribution of lateral loads (from wind or earthquakes), on the diaphragm action of the roof and floor systems. To this end, independently of the type of the floor units, the diaphragm action of the entire floor has to be secured. This can be achieved through adequate connections between the floor units, with or without the use of cast in-situ concrete topping, and by a proper horizontal tying system.

4.3.4 Frame systems 4.3.4.1 General

Different solutions have been developed in the precast industry when frame systems are used. Generally their type varies according to the height and use of the building and the seismicity of the area.

According to the way in which beams and columns are connected, two main categories of

frame systems may be identified: − hinged beam-column frame systems with cantilever action of the columns, − moment resisting beam-column frame systems.

4.3.4.2 Beam-column hinged frames

Beam–column hinged frames usually consist of one-piece columns (along the whole height of the building) and simply supported beams with the vertical load path provided through direct support on corbels or on the top of the columns, depending on the number of the storeys.

The columns are fixed to the foundation with moment resisting connections (Fig. 4.3-1c). In Fig. 4.3-3 and Fig. 4.3-1a, the static scheme of such frames is presented.

Fig. 4.3-3: Beam-column hinged frames



Such frame systems are widely used mostly in low-rise buildings because they are relatively simple to build and also economical, thus some of affordable housing systems have adopted this kind of structure in part.

Usually in the frame direction the hinged connection is made by the use of two parallel

dowels which are properly anchored in the body of the column (or in a corbel) and make the connection of the beam against horizontal shear actions by means of in-situ grout, which surrounds (and activates) the dowels and fills the slots at the beam ends.

These two parallel dowels, mobilize also a certain protection against lateral overturning of

the beams, which can be inducted by the seismic action, by mobilizing a lateral moment resistance of the connection.

In Fig. 4.3-4 and Fig. 4.3-5 typical details of a hinged beam-column connections are

shown schematically

Fig. 4.3-4: Typical arrangement of a hinged beam-column connection on the top of a column (in this sketch, the secondary beam serves also for water flow) [42]



Fig. 4.3-5: Individual precast members according to Fig. 4.3-4

To ensure structural stability:

i) Cantilever action of the columns may be assumed for buildings up to three levels but not in areas of high seismicity. In this respect the columns are continuous (one piece) for the full height of the structure and are fixed to the foundations by moment-resisting connections to act as cantilevers when exposed to horizontal loading due to wind forces or earthquakes (Fig. 4.3-6). To this end column-to-foundations connections should be properly designed. In seismic areas, columns should be designed and detailed not only for strength but also for ductility. It is possible to achieve sufficient ductility in this kind of structure by providing enough confinement reinforcement within a length of two depths of the column at the base.

ii) Wherever the height of the building is more than 3 or 4 floor levels, and always in areas of higher seismicity, shear walls or boxes made by precast concrete or cast-in-place concrete should be preferred to secure the lateral stability and stiffness of the structure.



Fig. 4.3-6: Schematic presentation of deformations and bending movement distributions in an

unbraced three storey high hinged frame structure due to lateral loads [31]

In Fig. 4.3-7 an example of a stabilizing system in braced frames is presented schematically together with indication of the flow of internal reactions due to horizontal loading in x and y directions. In such cases the horizontal “floor-diaphragm” system as well as the vertical “stabilizing system”, should be carefully designed.

Particular attention should be paid also in the arrangement of the walls into the structure to

achieve balanced resistance to horizontal forces. In Fig. 4.3-8 an example is given of how the torsion induced by an eccentric position of a core should be balanced by suitable arrangement of shear walls.

Fig. 4.3-7: Example of stabilizing system in braced frames [31]



Fig. 4.3-8: Shear walls are needed to balance the torsion induced by the eccentric position of the core [30]

4.3.4.3 Moment – resisting beam – column frame systems

Precast moment-resisting frames are constructed by a set of precast elements (columns and beams) or precast units of different forms suitably connected together to form a stable frame system (Fig. 4.3-9) able to meet the requirements of a corresponding monolithic one. These kinds of structures are more complex than isostatic ones and are seldom used in precast affordable housing systems. In any case the concepts and details used in their development are useful for affordable housing systems in high seismic areas.

Fig. 4.3-9 Schematic presentation of deformations and movement distributions in a moment-

resisting beam-column frame system [31]



For precast moment resisting frame systems usually the “emulative design” is used. That is, these systems are designed to closely emulate the response of conventional cast–in–place reinforced or prestressed construction, in terms of stiffness, strength and, in earthquake areas, in terms of ductility capacity and energy dissipation characteristics.

Moment resisting frames are arranged to provide lateral force resistance in one or two ways, see Fig. 4.3-10.

Fig.4.3-10: Classification of precast concrete moment-resisting systems according to the in

place lateral force resisting mechanisms [41]

Such frames, with or without additional lateral resisting systems such as shear walls, may

be used for low or high-rise buildings independently of the seismicity of area.

As a rule precast moment-resisting frames are complex to build, especially for the connections to achieve continuity at the supports, are costly and demand a rather high technological level to build. For these reasons, they are not much used for affordable housing. 4.3.4.4 Structural integrity of frame systems

In all cases of frame systems (and, generally speaking, in all precast systems), a suitable interaction of the bearing elements of the system (beams – columns – walls) with the floor system should be secured to ensure the structural integrity of the total structure. To this end, a set of adequate connections (contributing to force transfer continuity and ductility) should be provided between all structural parts of the systems. This is usually obtained through a three-dimensional network of ties (Fig. 4.3-11).

Ties are continuous tensile elements consisting of reinforcement bars (or sometimes tendons) placed in cast in-situ infill strips, sleeves or joints between precast elements, in longitudinal, transversal and vertical directions. Their role is not only to transfer normal forces (between units) originating from wind and other loading (e.g. earthquakes), but also to give additional strength and safety to the structure to withstand to a certain extent accidental loading, gas explosions, collisions, etc.



Fig. 4.3-11: Types of ties in skeletal frames [31] 4.3.4.5 Column to foundation connections of frame systems

Precast frame buildings without shear walls, and especially when only beam-column-hinged frames are used, depend on the moment capacity of the column base to resist lateral loads. The ability of a footing to resist moments is dependent on the type of the column-to-foundation connection and on the rotational characteristics of the base.

The most common type is the pocket foundation, which is highly recommended on good soils, independent of the seismic area. The pocket should be wide enough to enable a good concrete filling around and below the column. It is very advisable in seismic areas to use pockets with keyed surfaces. Pockets may be prefabricated or cast by in situ concrete. In this case the concrete grade should be at least C30/37.

In Fig. 4.3-12 a typical pocket foundation is presented schematically, together with a

simplified model of the force transfer (4.3-12b). In Fig. 4.3-13 an example is presented, with a possible arrangement of the pocket reinforcements.

In some cases column to foundation connections are realized by means of steel base plates

with external (see Fig. 4.3-14a) or internal (see Fig. 4.3-14b) anchor bolts.



a) b)

Fig. 4.3-12: a. Pocket foundation b. Simplified model for the force transfer in a pocket foundation [37]

Fig.4.3-13: Pocket foundation with smooth surfaces and possible arrangement of

reinforcements



Fig 4.3-14: Steel base plates with external or internal anchor bolts [34]

4.3.5 Wall systems

A wall system is composed of load bearing walls with floors and roofs made of solid panels, hollow core units, floor plank systems, etc. Depending on the arrangement of the bearing walls in the ground plan and on the serviceability needs of the building, non-bearing panels (plain or of sandwich type) are also used as partition or façade walls (see Fig. 4.3-15).

Fig. 4.3-15: Illustration of an integral wall system



The type of a prefabricated building is best described by the arrangement of the load bearing structural units. Depending on the orientation of the main load bearing walls relative to the long axis of the building, we can distinguish: • cross-wall systems, where load bearing walls run at right angles to the long axis of the

building (Fig. 4.3-16b); • long-wall systems, where the load bearing walls are placed longitudinally, parallel to the

main axis of the building (Fig. 4.3-16a); • two-way span systems, where the supporting members run both longitudinally and

transversely (Fig. 4.3-16c).

Fig. 4.3-16: Arrangement of load bearing walls in buildings: (a) cross – wall system, b) long – wall system, (c) two-way span system Wall systems generally provide good horizontal stability, ensured by means of cantilever

action in walls (and/or cores). The acting horizontal loading is distributed (through the diaphragm action of floors) over

the different walls and cores proportionally to their respective stiffness. When walls have rather large openings, for example for doors, it should be checked whether the part of the wall above the door opening could contribute.

The different storey height superposed wall panels have to be connected to each other in

such a way that the total wall can function as a cantilever. In Fig. 4.3-17 the response of such units in vertical and horizontal loading is presented schematically.

The prevailing actions in connections between individual walls units are: • shear forces in the vertical joints (Fig. 4.3-17); • compressive forces in the horizontal joints, accompanied by shear forces and bending

moments (Fig. 4.3-18);



Fig. 4.3-17: Load deformations and shear forces in wall structures

Fig. 4.3-18: Schematic presentation of actions on horizontal joints. [41a].

Shear connections, from the point of view of strength and ductility, are mostly of wet keyed type, with connecting reinforcement by mean of loops (Fig. 4.3-19).

In Fig. 4.3-20 some typical shear connections in horizontal section are presented, in which

lateral loops across the joint and longitudinal reinforcement along the joint are shown.



lj = length of the vertical joint between

floors t = thickness of the precast panel tj = middle thickness of the joint concrete ao = slope of the key (45o÷60o

recommended values) n = number of keys along lj a = thickness of the key inside the panel

(1.5÷3cm) b = width of the joint, b ≥ t ho = length of the key inside the precast

panel h1 = distance between keys

n ⋅ ho

l j

= density of the keys (≤ 0.5)

Astr = transverse reinforcement (loops) Asl = longitudinal reinforcement lb = proper anchorage of the loops main reinforcement of the connection

and of the precast panels additional local reinforcement

Fig. 4.3-19: Typical shear connection [41a]

Fig. 4.3-20: Horizontal sections on typical shear connections



In order to ensure structural integrity it is also necessary to realise a three-dimensional coherence between the different elements. To this end, vertical and horizontal connections between the panels themselves as well as between panels and floor units should be properly designed. Also adequate tie-reinforcements should be provided in all directions (Fig. 4.3-21).

Fig. 4.3-21: Schematic location of ties in spine wall structure [33]

According to the cross section of the walls we may distinguish between the following types of load-bearing walls:

• Plain walls, Fig. 4.3-22 and Fig. 4.3-23, are the most commonly used in affordable housing, even with small thickness.

• Sandwich walls, Fig. 4.3-24, composed of two concrete layers and one of insulating material. Such walls are mostly external and, in case they having bearing function, their internal concrete layer is provided with suitable thickness (≥ 150 mm) and reinforcement. Not normally used in affordable housing due to their complexity and cost.

• Double walls, Fig. 4.3-25, composed of two precast elements, suitably reinforced and connected to each other during production. Such elements are placed adjacent to each other, and, after positioning of the slab elements and the additional reinforcement, in situ concrete is poured above the slabs and between both precast layers. In this way the final structure is similar in behaviour to monolithic reinforced concrete structures. In Fig. 4.3-26 some typical connections between double walls are shown schematically, and in Fig. 4.3-27 typical connections to their foundations are presented.



Fig. 4.3-22: Plain wall with door opening

Fig. 4.3-23: Plain wall with large window opening in which connecting and assembly reinforcement are shown



Fig. 4.3-24: Bearing wall of sandwich type with openings

Fig. 4.3-25: Typical double wall system [38]



Fig. 4.3-26: Typical double wall connections in horizontal cross sections

a) bearing wall of bearing sandwich type b) double wall Fig. 4.3-27: Typical details of connections between walls and their foundations

4.3.6 Floor systems

There are a variety of precast floor systems, which may be used for any type of precast structures but are also suitable for monolithic ones.



The most common types for dwelling are the following.

• prestressed hollow-core floors (with or without structural topping)

• double Tee ╥ or Π slab floors

• massive slab floors

• plank floors (reinforced or prestressed)

• beam and block floors

The main structural requirements of floors are span load bearing, transverse load distribution of concentrated loadings, and distribution of horizontal actions by in-plane diaphragm action, as well as the ability to handle the effects of accidental actions affecting it or its supporting structures. In addition, depending on their use, floors can also have to fulfil other requirements such as acoustic insulation, fire resistance, etc.

From the above floor systems, the first three may be used also without cast in place

concrete topping depending on the live loads and the span of the floor elements. Principally topping deals with the diaphragmatic performance of the floor system, and with better load transfer between the precast members of the floor. Plank floors are always used with additional in situ concrete, while beam and block floors are used by in situ concrete filling usually combined with concrete topping.

Whenever structural topping will not be used, particular attention should be paid on the

detailing of the connections of the adjacent individual precast members due to the tendency for different vertical deformations and to shear stresses along the connection arising from the diaphragm action of the whole floor.

Fig. 4.3-28 shows a schematic presentation of actions on horizontal joints between floor precast members, diaphragmatic actions included. Fig. 4.3-29 presents a simplified model of flow of actions for joints of precast floor members. Fig. 4.3-30 shows a schematic presentation of the mechanism for lateral load distribution for floors made by hollow-core-slabs.



Fig. 4.3-28: Schematic presentations of actions on horizontal joints between floor precast

members [37]

a) b) c)

Fig. 4.3-29: Simplified model of flow of actions (a and b) [37] Principal stresses inside and around the connection (c)

Fig. 4.3-30: Schematic presentation of the mechanism for lateral load distribution in H-C-S

floors. [31]



Plank floors are always composite and the precast pre-slabs contain the main slab reinforcement together with possible connecting reinforcement with the cast in-situ concrete topping. In Fig. 4.3-31, a cross section of a composite plank floor is presented schematically, in which typical reinforcement is also shown.

Fig. 4.3-31: Schematic presentation of a plank floor

Beam and block floors are made by rather shortly spaced (0.4 – 0.8 m) precast joists, prefabricated infill block usually of ceramic material or other, and in-situ concrete filling usually combined with an integral concrete topping. These kinds of floors are used with a high variety of mixed construction in affordable housing.

Fig. 4.3-32: Example of a typical beam-block floor. In-situ concrete filling and integral concrete topping are not shown. [39]

Prestressed hollow-core-slab units are manufactured using either long line extrusion or slip form process to have longitudinal cores of which the main purpose is to reduce the weight of the floor. They are used for every type of buildings such as apartment buildings, hospitals, schools, shopping centres, and suit for rather large spans of the floors. They are characterized by their favourable cost/efficiency ratio and the fast erection. Normally small kind of hollow core slabs for small spans, either reinforced or prestressed are used in some mixed affordable housing systems.



The edges of the units are suitably profiled to ensure vertical (sometimes also horizontal) shear transfer across the grouted joint between adjacent units (see Fig. 4.3-33).

Extruded elements Slipform elements

Fig. 4.3-33: Typical hollow core slab cross-sections [30]

In order to achieve structural integrity, floor systems consisting of individual precast concrete units should be tied together by a tying system to form an entity, either with or without a cast in-situ structural topping over the whole precast floor surface.

In Fig. 4.3-34 some tie arrangements in a hollow core floor are presented schematically.



Fig. 4.3-34: Horizontal ties in hollow-core floors [31]

In order to ensure the diaphragm action of a precast floor system, which is needed for the transmission of the horizontal loads from wind, earthquakes, etc., to the structural system of the structure, tensile, compression and shear forces (created from the diaphragm action of the floor), should be carefully estimated and covered with suitable reinforcement accordingly.

To this end, design models (arch-and-tie or strut-and-tie) should be used according to the type and arrangement of the vertical resisting members of the structural system, as well as of the type and arrangement of the floor units.

In Fig. 4.3-35 some possible models are presented, based on the arch-and-tie scheme. 4.3.7 Stairs

Precast concrete stairs are rather industrialized products with high degree of finishing ranging from smooth as cast to polished concrete. Compared to in-situ solutions they are particularly cost effective, especially in the case of a reasonable amount of repetition, as in the case of multi-storey buildings. Different types of stairs may be built according to the different needs of each particular case.



a) Analogous plate girder

b) Force distribution in floor diaphragm

Fig. 4.3-35: Simplified models of diaphragm action based on the principles of the “horizontal

deep beam analogy” [30]



Fig. 4.3-36: Typical stair construction using precast stair members [36]

4.4 Production, transportation and erection process

In developing countries, the production, transportation and erection process play a significant role in the expansion of local prefabrication technologies. It is necessary to take into account the fact that roads could significantly limit the possibility of transportation and it will therefore be necessary to adapt production and transportation to this limitation. Moreover, the components to be manufactured should be limited, at the beginning, to those that can be easily erected on the work site without assistance of heavy equipment. In fact, in some countries, the prefabrication approach has been difficult to introduce due, in part, to a shortage of equipment needed for casting, curing, transportation, and lifting of modules [43]. 4.4.1 Production 4.4.1.1 General aspects of production

Precast elements are generally constructed under factory conditions, as the quality of the work is easier to control than on a construction site. However, in some contexts, it will be also possible to look at in-situ prefabrication.

For a well-established prefabrication industry, the production unit mainly calls for: • large scale use of machines; • large scale use of factory produced standardized building components; • co-ordination of management leading to efficient planning, programming, and control

of projects; • continuous research in design and production systems.

The main essentials and advantages of prefabricated production will be:

• avoiding waste; • standardization of repetitive work; • creating a uniquely custom product; • reduction of resource idleness; • reduction of average waiting time; • reduction of time between deliveries of finished products;



• reduction of variability; • decrease in time for processing parts to traverse the system; • decrease in costs; • reducing inventor; • increase in production rate.

The reduction of waiting time and resource idleness can be overcome by ensuring that

crews move in parallel for erection and grouting activities. Decrease in time for processing parts is assured by using the innovative methods developed herein and by assuring that crews are occupied through low resource idleness. Collectively, the above ensure high production rate, and cost reduction occurs due to the economies of mass construction.

Production units require storage of raw material such as cement, steel, aggregates, lime, timber, etc., and hence extensive storage is done in stockpiles, yards, silos and warehouses. A machinery yard is also necessary to house the various cranes, concreting and material handling equipment. Adequate stacking area for the finished products such as wall panels, floor panels, etc., is required, as they have to be maintained in stock. Thus storage arrangement becomes one of the primary functions of the production. Production should be planned in such a way that the panels have aged some days before they are erected.

Next in importance are industrial sheds, wherein the prefabrication company will manufacture the various building components. These industrial sheds may have gantries and other such facilities. The administrative wing, sales and service wings, design offices, training wing, the computer centre and production control offices are some of the other units which will be required. Railway siding, wide roads, water and power supply and security arrangements are also to be provided.

The transportation wing is another important area for the transportation of the finished products to the building sites. A large vehicle parking lot in front of the industrial estate can also be envisaged.

Modern methods of housing manufacture and erection, utilizing principles such as computer integrated manufacturing (CIM), flexible manufacturing systems (FMS), and lean manufacturing coupled with innovative ideas can hope to erect houses at fast speed and high quality. The balance between site and factory processes and the optimum level of prefabrication for housing designs can be analysed using software tools such as DSM (Dependency Structure Analysis), a system analysis tool for the investigation of interactions and interdependencies between elements in a complex system. Used on the architecture of the product, DSM determines possible integrative components, in other words, it seeks potential for employing larger factory pre-fabricated modules. Used on the assembly process, DSM creates optimised task sequences that can be fed into planning tools to determine the critical path for the assembly process. 4.4.1.2 Special light elements

The production of light elements that can be moved and erected by few non-specialized people, without the help of machinery, may play an important role in developing countries. There exist some examples in the technical literature [29], [43]:

• blocks for walls, • panels for walls, • ferro-cements wall panels,



• pre-cast lintels, • ferro-cement over-hangs with lintels, • cantilever stairs, • joists and plank system, • RCC precast door and window frames, • ferro-cement shutters for door and windows, • structural columns, • ferro-cement water tanks.

4.4.1.3 Floor units

The production techniques vary according to the type of the floor unit to be produced. The techniques also vary depending on whether they are reinforced or pretensioned.

Solid slabs are mostly produced in strips of 1.2 to 2.4 m width when they are cast on a long line, but are made as room size panels when they are individually cast using timber or steel. Cored slabs too are produced in a similar manner as solid slab. The cores can be formed, in both the case of reinforced and pretensioned floor units, by means of polyurethane foam which is bundled in polythene sheets or by using rigid cardboard pipes.

Hollow-core units are produced without core forms. Ribbed floor units may be in the form

of a single or a double tee, or a channel section. Single as well as double tee floors units are produced by using rigid steel formwork. 4.4.1.4 Wall panels

There are two types of wall panels used in prefabricated buildings: external cladding walls and internal partition walls. These walls maybe load bearing or partition walls. The production technique for producing external wall panels is different from that of partition walls.

The external wall is normally of a sandwiched type incorporating the thermal insulating material in between its two vertical faces. The panels are cast horizontally using tilt-up moulds. At first, a thin layer of concrete forming the external, non-structural layer is cast. Over this is placed the insulating material such as polyurethane foam in the form of thin strips. Stainless steel ties connecting the external non-structural concrete layer to the internal structural layer are then inserted and the structural layer of concrete is then laid to the required thickness. The external concrete layer is adequately reinforced with wire mesh to take up the thermal stresses. 4.4.2 Transportation

The size of the panels and slabs are limited by the transportation used to deliver them. By limiting the lengths of the panels and slabs to 12 meters and the widths to 3 meters, standard trailers can be used, assuming there are good road conditions.

Larger size panels and slabs may be used but special permitting and routing to the construction site may be needed, adding to the cost of construction. Smaller size panels will be recommended if the road conditions are not acceptable or/and it may not be taken into account the help of cranes.



Coordinating delivery so that the panels arrive as they are erected adds to efficiency, but because of the flexibility of this system this is not critical. 4.4.3 Erection

In developing contexts, as it has been previously commented, the erection process will be a key point for the design of prefabricated elements. The maximum weight that can be manipulated without cranes could be around 100 – 160 kg [43].

In other circumstances, tower cranes and boom cranes are generally employed, depending upon the weight, dimensions and erection height for the handling the erection work. It is desirable to simplify site erection by reducing the number of parts that are required to fulfil a whole building again this will increase the weight and dimensions of the part, so a balance between the number of elements and the dimension should be made to have economy in construction.

4.5 Waterproofing and insulation

A shelter’s “thermal envelope” separates outside conditions from inside conditions. This envelope consists of the components of all six sides of the house: the four walls, roof, and foundation. The roof is the most important part of the home to insulate in all climates [42]. In hot weather, the sun beats directly on the roof. Even though heat moves in all directions by radiation, in cold weather, heat loss out of the roof or attic is a particular problem because hot air rises. Wall insulation is far more important in a cold climate than a hot one. Floor insulation is very important in areas where the ground freezes.

At the same time, adequate ventilation shall be provided to maintain a healthy environment inside the house and to limit the risk of transmission of diseases. Ventilation should be maximised in hot-climates to reduce inside temperature, and minimised in cold-climates to retain heat within the shelter.

Affordable housing should take local climatic conditions into account and be designed to minimise the use of energy. Insulation of roof and external walls is important to minimise energy demand and provide internal comfort for the occupants. Climate variations should have an important impact on planning and designing affordable houses. In next paragraphs, key points for hot dry climate, hot wet climate (tropical areas) and cold weather will be highlighted [43].

In hot dry climates, shade from the sun is a basic concern. Several key design considerations should be taken into account:

• small windows to prevent high solar gain during the day and heat loss at night; • position doors and windows away from prevailing winds, as they can be really hot; • thermal mass in buildings should be ensured by constructing thick walls and insulating

roofs (by means of thermal mass or creating an air chamber).

In wet climates, draining water will be the principal consideration, therefore: • construction in sites with slope to provide adequate surface drainage; • roof with sufficient pitch for water drainage. Drains connect to reservoir to harvest

rainwater;



• roof overhang to protect walls and openings from water during rainy seasons and from sun in hot weather;

• compacted plinth, with raised floors to protect from flooding; • provide sufficient openings (with small windows) for good ventilation and air

convection.

In cold climates, heaters are an essential part of the heating strategy for a shelter. Once the room has been heated, it is important to ensure that the heat does not escape. For that reason, some key design considerations should be considered:

• use of materials with high thermal mass and added insulation; • strong roof to resist heavy snow loads; • small window will prevent heat loss, but ventilation is always necessary to prevent

respiratory diseases; • divide large rooms into several small ones.

In any case, all cultures have developed adequate and affordable housing solutions; if these

are used as a starting-point, appropriate housing is easier and cheaper to provide. Participation of the beneficiaries, even with respect to waterproofing and insulation, will be important, as the final design should be in accordance to their beliefs and habits. For example, in some countries like Indonesia, where torrential rains are common, it is usual to raise floors to avoid water floods. Some inhabitants believe that a house at floor level facilitates the access of evil spirits, and if houses are not elevated, the habitants could even reject the new constructions. 4.6 Services and installations

Ideally, prefabricated construction should comprise of a number of pre-engineered panelled or sectioned building elements and units designed and prefabricated to include all of the basic services such as wiring, plumbing, and ductwork.

Affordable housing when initially constructed may not always include such services. If this is the case the selected construction system should allow for future installation and integration of services.

Affordable housing should take local climatic conditions into account and be designed to minimise the use of energy. Insulation of all external walls and roof is important to minimise energy demand and provide internal comfort for the occupants.

Where possible the orientation of the house should reflect the climatic conditions. Elevations facing the sun should be designed to reflect heat in summer and gain heat in winter. This can be accomplished by appropriate configuration of windows and roof overhangs. Through-ventilation should be provided to take advantage of cooling winds.

Water supply is vital in all housing and this can be provided by installation of a water tank to collect rainwater from the roof. Water distribution can be collected direct from the tank or piped by gravity or pumped systems to within the house.

Economy in plumbing services can be attained by the use of single stack system for

plumbing. This is a one-pipe system in which the wastes from both the kitchen and toilet are carried out of the building in a single stack. The service stack itself serves the purpose of a ventilation pipe and eliminates the need for a separate ventilation stack. It embodies the



merits of both the conventional two-pipe system and the modern one-pipe system. The use of this system gives a savings of about 30 % in the plumbing work.

For economy in wiring, electricity can be distributed using a ring circuit system in place of conventional multi-circuit systems.

The prefabricated panels should be designed so as to provide basic services of storage in the form of cupboards. Properly ventilated lofts at around 2.1 m level for a width of about 0.6 m will be useful in bedroom, dining hall and kitchen.

Special attention must be given to the design of kitchens and bathrooms, as their relative position in the house responds, very often, to local beliefs or climate facts.

In India, for example, some affordable houses were designed following western standards: small bathroom between two bedrooms, dinning room – sitting room with a south oriented veranda and a kitchen in the northwest corner. The beneficiaries, mostly in rural areas, did not use the bathroom, which was turned into a small storage room. The veranda, one of the most used spaces in the Indian culture, was always empty, and they did not use the kitchen, as they continued cooking outside the house. After some research, the project leaders learnt that most Indian houses have the bathroom attached to the house, but with an independent entrance.

They also realized that the kitchen should be oriented to east, as many Hindu people perform a ritual in that direction before cooking. Finally, the best orientation for a veranda in a really hot area was north. As this small real life example highlights, the observation of the local constructions and the participation of the beneficiaries in design, would have helped to build a more accepted and useful construction.

5 Examples of housing systems

A large number of industrialized housing systems that are used in several parts of the world have been studied. Among all these systems, some have been selected for presentation in this bulletin.

The systems were selected depending on several basic ideas. They all are industrialized systems that are used in their respective environments for affordable housing. The systems were also selected because they have at least some important part that was built with precast concrete elements. There are systems with at least precast foundations, walls, columns, beams or decks.

The part of the world where the systems are used is relevant when selecting systems. In this case, more systems from America were selected due to the fact that more systems have been developed and their information was available. Systems from other parts of the word were not so easily available.


42 5 Examples of housing systems

Another characteristic for choosing a system is that there is an all around catalogue of different types of systems. Some aspects that were studied are:

• country

• material − concrete − mixed

• structural system − wall − frame − mixed

• climate − dry − wet − flooding − medium

• seismicity − high − low − none

• construction − contractor − self built − both

• incremental construction − yes, no

• handling capacity − <1.5 t − <5.0 t − >5.0 t

• level of technology − low − medium − high

• installations included − yes, no

In the following table the name of the system is given along with the country where it is used and the number assigned to it.



Table 5.1: List of example housing systems

Number Name Country 1 Unidade Habitacional De Baixa Renda Brazil 2 Beno Argentina 3 Capro Argentina 4 Centro Cooperativista Uruguayo Uruguay 5 CEDAS. Habitplan Consultores Uruguay 6 Horpresa Uruguay 7 M 47 Uruguay 8 Paneles Integrales Prefabricados en Obra Uruguay 9 PNV Uruguay

10 STUP Uruguay 11 SISTE - PLAK Uruguay 12 Cojan Engenharia Brazil 13 ÉSCOLAS EM PRÉ-FABRICADOS LEVES Cedec/Emurb Brazil 14 Escosa Costa Rica 15 Servivienda Colombia 16 Structurapid-Depetris Chile 17 Simplex Chile 18 Matla Housing System South Africa 19 Baumeister Alfred Noll Austria 20 SEVIPS – Greek National Association of precast concrete

producers Linear Precast Elements System Greece

21 Organisation of School Buildings, Demountable School Buildings made of 3D units

Greece

22 Organisation of School Buildings, School Buildings made of precast walls

Greece

23 Gruppo Centro Nord. Forap hollow core housing system. Italy 24 Multipref S.A. Costa Rica 25 Zitro S.A. Costa Rica 26 Concrete Houses . Hollow Core Concrete P/L Australia 27 Tangram Prefabricados. Tangram Ind. e Comércio Ltda. Brazil 28 Tangram Pro. Tangram Ind. e Comércio Ltda. Brazil 29 Castelo Spain 30 Caribbean Homes Barbados 31 Cassol Pré-fabricados Brazil 32 Brasitherm Engenharia Ltda Brazil 33 BPDL Precast Concrete International ¨BPDL CASA¨ Canada 34 Sudeste Construção Industrializada Ltda. Brazil 35 Locrete Locrete Industries Kuwait 36 Load Bearing Concrete Panel – PREMO - Belo Horizonte Brazil 37 Keriva Poland 38 Izhar's Precast Housing System Pakistan



DESCRIPTION OF THE SYSTEM: This system:

• uses panels both for wall and slab elements. All of them are made of reinforced concrete. Every component of the system is prefabricated at a fixed plant.

• consists of precast concrete ribbed panels fixed to a reinforced concrete in situ foundation

and joined between them trough a dry connection; the slabs are directly rested on to the panels; coatings and door and window frames are included in the panels. Finally, traditional solutions for the cover can be used.

• allows incremental construction.

Installations must be incorporated at the work site. Maximum dimensions of the panels are 0.04 m thickness, 1.20 m width and 3.70 m length, with a maximum weight of about 310 kg. Only one height is allowed.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry X Wet X Flooding Seismic resistance: High Low None X Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes No X

1



GRAPHIC INFORMATION:

REFERENCE: CYTED. Catálogo Iberoamericano de Técnicas constructivas Industrializadas para vivienda de interés social.

1



DESCRIPTION OF THE SYSTEM: This system is made of light plates, prefabricates and reinforced ceramics. These plates, which can be built in the work site or in factory, have the electric installation incorporated. Foundations are made on a concrete base with a floor-boarding joist. Exterior and interior load bearing precast concrete panels with internal isolation. Joints are grouted to join panels and floors. In situ concrete floor topping. There is no need of cranes to erect panels. Maximum dimensions of panels are 0.06 m thickness, 0.43 m width and 3.0 m length. Maximum number of floors is two. The system rationality allows: decrease the men hours in the site-building, so that allows the community made components in their own housing or in a community production company in the original settlement (plaques, concrete windows, etc.).

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self Both X Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes X No

2





2



DESCRIPTION OF THE SYSTEM: This system consists of a basic material: in situ cellular concrete with foam agents. Foundations are moulded previously “in situ” and, on top of them, are connected panels. Moulds are made exclusively of steel. Panels may have every installation incorporated. Inclined ceilings are made with a reinforced concrete slab. Maximum number of floors is one.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self Both X Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes X No

3





3



DESCRIPTION OF THE SYSTEM: This system uses prefabrication for foundations and floors. Both ceramic and concrete are mixed to produce precast elements. In foundations precast concrete beams are placed on massive concrete blocks. In floors and ceilings precast elements are precast using concrete and bricks. Moulds are made from steel and wood. Maximum dimensions of elements are 5m in length, 0.40 m in width and 0.05 m in depth. Weight is about 200 kg. Maximum number of floors is two.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self Both X Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

4





4



DESCRIPTION OF THE SYSTEM: This system is dedicated to floors, mainly using a ribbed precast concrete element in inverted U design. Spans range between 2.0 and 3.60 m, with a width of 0.40 m and 0.15 m depth in ribs. Thickness of slab is ranging 0.02 and 0.04 m. Once the slabs are erected on site the work is finished with a concrete topping of 0.03 m thickness. No scaffolding or propping is needed in the process. No finishing is applied on lower part of slab as is coming from mould. Reinforcement is normally done from steel mesh. Other small elements are also precast.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame X Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self Both X Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes No X

5





5



DESCRIPTION OF THE SYSTEM: This system is characterised by external load bearing walls made of precast reinforced concrete, with a cross section in U form and width of 0.435 m and length of 2.465 m. Thickness varies from 0.03 to 0.07 m. The connection between walls is made with the help of bolts and then is sealed with elastic mastic. In doors and windows columns are places to be connected with the walls. Walls are placed on foundation precast beams. Also on the roof the walls are connected to a reinforced beam that distributes the loads to the walls. The interior part of the wall is finished with an in situ polystyrene of 2 cm thickness. The deck is built with inverted T precast prestressed beams and concrete blocks, everything is fixed together with an in situ topping.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self Both X Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

6





6



DESCRIPTION OF THE SYSTEM: Foundations are made on a concrete base with precast concrete beams, supported on piles joined together with in situ concrete. Load bearing walls are erected with cranes and levelled. The size of elements is 2.35 m width, 0.20 m thickness and 2.40 m length Floors are made with hollow core slabs that are erected on top of the load bearing panels. Joints are grouted to join panels and floors. In situ concrete for topping. Also a 5 cm thickness precast slab is used. Inclined ceilings are made with the 5 cm thick slab or with fibrocement planks.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self X Both Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes X No

7





7



DESCRIPTION OF THE SYSTEM: This system is characterised by load bearing precast concrete foundation beams, exterior and interior load bearing precast concrete panels, reinforced with steel wire mesh and internal isolation with 2 cm of polystyrene. All panels are 12 cm thickness and include openings and installations for water. Floors can be made from several types, from hollow core slabs to prestressed slabs. Joints between panels and foundation beams are grouted during erection. Joints between panels are grouted and reinforced with 3 steel wires and a reinforcing rod. The dimensions of panels are 4.0 m in length, 3.50 m in width, 0.12 m in thickness and 3.000 kg in weight.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes X No

8





8



DESCRIPTION OF THE SYSTEM: This system is characterised by prefabrication in concrete of load bearing panels. The panels are made in moulds of 3.6 to 6.0 m length in which any size on panel can be solved. There are several types of panels:

• Load bearing panels: built with two 6 cm thickness panels, joined by in situ concrete. The panels are separated in a the way the structural calculation is needed.

• Separating walls: also 6 cm of thickness • Floors and ceilings: pre-slabs with in situ topping • Exterior panels: of thickness from 6 cm to 15 cm. With opening finishing.

Connections solved with steel elements and grouting.

BASIC CHARACTERISTICS: Materials: Concrete X Steel X Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes X No

9





9



DESCRIPTION OF THE SYSTEM: This system is characterised by prefabrication of foundation blocks and beams, columns and floors. Placement of foundation blocks: on top of the blocks are connected the columns and after the foundation beams, the floor beams are erected on top of the columns and joined together by in situ concrete. The floors are made with prestressed pre-slabs finished with in situ topping. Maximum dimensions of slabs are 0.07 m thickness, 2.40 m width and 6.0 m length.

BASIC CHARACTERISTICS: Materials: Concrete X Steel X Mixed Structural system: Frame X Wall Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes No X

10





10



DESCRIPTION OF THE SYSTEM: This system is characterised by precast reinforced wall panels and precast foundation beams. They are connected by means of grouting which creates concrete columns in between. The panels are produced by two ribbed slabs connected by bolts. Thickness of the slab is 3.5 cm and ribs of 6.5 cm. Both slabs produce a panel of 20 cm. The air inside the panel creates insulation and economy of materials. Such small dimension force to produce concrete with maximum aggregate of 8 mm.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor X Self X Both Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes X No

11





11



DESCRIPTION OF THE SYSTEM: This system uses hollow cored panels both for the walls and the ceilings. The panels are made of reinforced concrete. Every component of the system is prefabricated. Prefabrication can be done at the work site. Consist of vertical and horizontal panels joined by grouted connections and founded on to a cast in situ reinforced concrete slab. Usual solutions for the cover can be used. The system does not allow incremental construction. Installations can be incorporated in factory and completed at the work site. Coatings must be done in the wok site. Maximum dimensions of panels are 0.12 m thickness, 3.00 m width and 3.00 m length, with a maximum weight of about 90 kg. Maximum number of floors is ten.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry X Wet X Flooding X Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes X No

12





12



DESCRIPTION OF THE SYSTEM: This system uses pocket foundation, columns, beams, slabs and panel elements. All of them are made of reinforced concrete. Every component of the system is prefabricated at a fixed plant. Consist of columns joined to reinforced concrete in situ foundations through pocket foundation element previously imbibed in it; segmental beams joined at work site resting on to the columns; slabs between the beams with a concrete top poured in situ to conform the first floor as well as the cover; and dividing and cover elements design according to isolate and watertight requirements. The system does not allow incremental construction. Installations must be incorporated at the work site. Maximum dimensions of lineal elements are 0.12 m thickness, 0.18 m width and 6.25 m length, with a maximum weight of about 340 kg. Maximum number of floors is two.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame X Wall Mixed High/low rise: High Low X Both Climate: Dry X Wet X Flooding X Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes No X

13





13



DESCRIPTION OF THE SYSTEM: This system uses precast concrete panels, columns and precast foundation blocks. These panels have some longitudinal holes to introduce steel wires and lighten the section. Joints between panels are grouted and reinforced with a reinforcing rod. Steel slabs on topping. Maximum dimensions of panels are 0.085 m thickness, 1.20 m width and variable length. Installations must be incorporated in the work site. Maximum number of floors is one.

BASIC CHARACTERISTICS: Materials: Concrete Steel Mixed X Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet X Flooding Medium Seismic resistance: High Low X None Contractor/self-built: Contractor Self Both X Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

14





14



DESCRIPTION OF THE SYSTEM: This system is characterised by prefabrication of foundation blocks, beams and floors. It is made of precast reinforced concrete panels. Maximum dimensions of panels are 0.03 m thickness, 0.97 m width and 0.97 m length. Vertical joints are connected with steel or wood ties. These ties are introduced in clasps perforated in horizontal joints. Inclined ceilings are made with fibrocement planks. Installations must be incorporated in the work site. Maximum number of floors is two.

BASIC CHARACTERISTICS: Materials: Concrete Steel Mixed X Structural system: Frame X Wall Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor Self Both X Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes X No

15





15



DESCRIPTION OF THE SYSTEM: This system uses precast reinforced concrete foundation blocks, columns, floors and ceiling. Any structural material can be used for walls. It consists of rigid concrete frames with “in situ” concrete joints. Installations must be incorporated in the work site and there is no need of cranes. Maximum dimensions of frames are 0.32 m thickness, 0.45 m width and 4.50 m length. Maximum number of floors is five.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame X Wall Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low X Med High Installations in system: Yes No X

16





16



DESCRIPTION OF THE SYSTEM: This system:

• is characterised by prefabrication of foundation blocks and beams, columns and ceiling. • uses reinforced concrete foundations with a floor-boarding joist and load bearing

reinforced lightweight concrete panels. Floors are made of wood. • is not able to putrefaction and also is fireproof.

Panels have every installation incorporated. The system rationality decreases the men hours in the site building. Maximum dimensions of panels are 0.095 m thickness, 1.20 m width and 2.40 m length. Maximum number of floors is two.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet X Flooding Medium Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes X No

17





17



DESCRIPTION OF THE SYSTEM: This system comprises external and internal walls of polypropylene fibre reinforced precast concrete walls which are thickened at the edges, and precast concrete columns at corners and T-junctions. The 100 x 100 mm columns are set into holes and crushed stone is rammed around them to a depth of 300 mm. The wall panels are set on in-situ concrete strip foundations. The thickened edges of the walls have holes to take the 12 mm diameter bolts, which secure the panels to each other and to the columns. The concrete floor is finally cast within the external walls. Conventional timber rafters or trusses are used for the roof construction. Wall panels are 2.700 mm high, 1.114 mm wide and 30 mm thick. The panel width relates to the width of standard doorframes. The wall panels are on the one hand light enough for manual erection and on the other hand heavy enough to prevent theft. Concrete design strength is 45 MPa. Reinforcement consists of 0.2% of polypropylene fibres. With an ideal number of six workers, five of which can be unskilled labourers, a conventional house can be completed in three days.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall Mixed X High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self X Both Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

18





18



DESCRIPTION OF THE SYSTEM: This system utilizes bolted timber beams as load bearing structure, and lightweight concrete panels for the flooring, wall- and roof-covering. The main building material is a lightweight concrete with expanded polystyrene (EPS) as an aggregate. By varying the polystyrene content, lightweight concrete of various densities can be manufactured to meet the specific requirements of the intended area of utilization. Light panels can be provided with a tongue and groove profile. The waste material of the milling station can be used as backfilling.

As a basic module of a detached, single-story, modular construction, it can be extended as desired by an appropriate arrangement of several similar types of houses. The complete building kit, together with all required materials, tools, etc., measures 2 x 24 x 6 m in delivery condition.

The foundation consists of prefabricated timber beams, which are bolted together. Light backfilling is used in-between the beams to provide a level foundation. Finally, a membrane is placed over the foundation to protect from rising dampness. The floor is constructed of light panels of 8cm thickness.

The load bearing structure consists of bolted timber beams. The prefabricated wall panels are fitted between these beams. The panels are dimensioned so that they can be easily carried and installed by one man. The individual wall panels are fixed to the timber beams with galvanized angle-connectors. The wall panels are set up side by side, joined together by a tongue and groove system and aligned and, for good measure, glued together with a PU foam. All the required block outs for the windows and the doors, which are also part of the delivery, are cut out on site, using a handsaw. The window and doorframes are subsequently glued in place with PU foam. The interior walls also consist of light panels of a density of 280 kg/m³.

The roof is designed as a simple single-pitch roof. The timber beams that make up the roof construction are also covered with panels of appropriate size and they are joined by tongue and groove connection. Finally, bituminous sheeting is placed over the panels which, in simplest case, are nailed in place.

All of the scaffolding required for installing the roof is erected from the transport pallets on which the panels were delivered. Five people can erect one module of about 30 m² in around 10 hours working time without the need of electricity or water – just with their bare hands.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Other X Structural system: Frame X Wall Mixed High/low rise: High Low X Both Climate: Dry X Wet Flooding Medium Seismic resistance: High Low None X Contractor/self-built: Contractor Self X Both Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

19




REFERENCE: Baumeister Alfred Noll, [email protected], T +43 676 5883003

19



DESCRIPTION OF THE SYSTEM: This system is characterised by precast linear concrete elements including prestressed (or not, depending on the spans) main girders, columns, secondary beams (gutters), TT slabs and sockets. The usual grid measures (15.00-30.00) m x (6.50-8.00) m. Hinged beam-column connections are realised by means of bolded dowels and in situ concrete. The roof is made of TT slabs (spans of 6.50-8.00 m, width of 2.50 m and rib depth 0.20-0.45 m) connected with the main girders by means of horizontal joints provided by steel (loops between slab ends and girders) and in situ concrete. Diaphragmatic action of the slabs is secured by additional connections along the transverse edges of the slabs by means of rebar and in situ concrete, or in adverse seismic conditions by 5-7 mm concrete topping. The foundation is composed by precast sockets and cast in situ fundaments provided with in situ connecting beams. Precast “sandwich” panels are used at the perimeter of the building and are placed in special recesses to be supported at the sides of the columns. The dimensions of panels are 6.50-8.00 m in length, up to 2.50 m in width and 0.16 m in thickness (2 layers of concrete 5 cm thick each and one layer of insulation 6 cm thick).

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame X Wall Mixed High/low rise: High Low Both X Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med X High Installations in system: Yes No X

20




REFERENCE: SEVIPS – Greek National Association of precast concrete producers

20



DESCRIPTION OF THE SYSTEM: This system is a demountable precast system. The system is based on precast concrete 3-dimensional boxes, ~25 m2 (3.60 m x 7.20 m) each. According to the architectural arrangement, the boxes are connected between themselves, horizontally by means of top welded steel plates in the case of one storey buildings and also vertically by means of vertical prestress (in the four edges of each box) in the case of two storey high buildings. Each box, 3.60 m x 7.20 x 3.50 m, is composed of: four walls at the perimeter (external or internal bearing walls), a roof slab and a floor slab. The horizontal and vertical connections among the walls and slabs of the individual boxes are provided of cast in situ concrete and reinforcement by means of loops. The boxes are produced at the factory and are transferred on site. The horizontal and vertical movements (due to earthquake actions) in the contact interfaces of the upper and lower boxes are controlled by tendons (ø6/10’,St1700/1900) passing through a vertical steel duct left in the panels at the four edges of each box. The prestress of the tendons is applied from the top of the second floor of the total building. The prestress can be easily deactivated in the case that the total building must be transferred and rebuilt in other sites (cutting also the welded plates which secure the horizontal cooperation of the boxes of each level).

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med X High Installations in system: Yes X No

21





21



DESCRIPTION OF THE SYSTEM: This system consists of precast concrete walls, of 7.20 m in length and 3.50 m in height. The internal walls are plane of thickness 15 cm. The external walls are of sandwich type composed of a concrete bearing layer of 15 cm, an insulation layer of 7 cm and an external non bearing concrete layer of 7 cm. The walls are produced at the factory and are transferred on site, where they are connected between themselves, according to the architectural arrangement, through horizontal and vertical joints, by cast in situ concrete and reinforcement by means of loops. The total thickness of the slabs is 35 cm and they consist of a 7 cm precast concrete slab, of in situ concrete ribs (12 cm thick), of insulating material between the concrete ribs and a top in situ layer to form the floor. This top concrete layer serves also to establish a monolithic connection with the walls at the perimeter of the slabs and to ensure the diaphragmatic action of the total slab. For that reason appropriate bars stand out along the edges of the slabs and of the walls, in every horizontal joint. The foundation is composed of cast in situ concrete beams and is connected with the walls with appropriate bars which exceed along the bottom edges of the walls.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med X High Installations in system: Yes X No

22





22



DESCRIPTION OF THE SYSTEM: This system consists of transversal bearing hollow-core wall slabs with crossing holes, bearing standard hollow-core floor and it is suitable for low cost housing construction particularly suitable in seismic and developing countries for social housing, construction due to the low costs and low weight of the components, together with the fact that it is prefabrication system approachable by any building contractor (even very small ones). The main feature of such system is that the bearing (horizontal and vertical) units forming the building frame are mass-produced, prefabricated at the plant and assembled in-situ, so as to reduce to the minimum both labour and yard equipment. The main components of FORAP building system consist of: 1) wall H.C. slabs, module 120 cm, depth 160÷200 mm 2) floor H.C. slabs, module 120 cm, depth 160÷300 mm During installation the floor slabs simply lean against the same positioning profiles of the wall slabs. In the final phase they lean upon the bearing walls maintaining at the same time a continuity connection with the adjacent bays. A bearing wall is obtained joining the various slabs by means of: a) a series of reinforcing steel bars inserted in the horizontal holes and running horizontally

throughout all the slabs so as to guarantee a valid mutual connection; b) a fluid concrete casting poured from the top filling all the cavities inside the slabs. The

entire wall becomes thus a reinforced concrete monolithic partition. The vertical connection between superimposed walls is secured by steel bar inserted when the concrete is still wet.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med High X Installations in system: Yes No X

23




REFERENCE: Gruppo Centro Nord, Italy

23



DESCRIPTION OF THE SYSTEM: In this system, moulds in the required wall shape are placed upon 3 x 15 m tilting tables. The necessary reinforcement or steel is then inserted into each element according to its design. The next step is to cast the concrete. This has to reach its specified resistance within 24 hours in order for the mould to be removed and the element moved. It is then left in a temporary storage space for a minimum of 24 hours. Water is applied to help it set and then finally it is transferred to a storage zone. All this transportation is carried out with the elements standing vertically – their most rigid position. Concurrently on site, work will have been engaged on constructing foundations which can be a conventional type or a slab foundation. Transporting the elements to the works’ site is carried out using “A”-shaped trestles so that the movement does not cause any damage. The last step in the system comprises setting the elements in place using a crane in a similar way to previous steps. Once in place, the elements join together creating a self-supporting unit. They are welded together at the places shown in the structural design.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low X Med High Installations in system: Yes X No

24




REFERENCE: CYTED. Catálogo Iberoamericano de Técnicas constructivas Industrializadas para vivienda de interés social

24



DESCRIPTION OF THE SYSTEM: This housing system involves creating walls using prefabricated structural panels which are set up manually. The lower part of these panels is embedded in a continuous foundation of concrete cast on site. The upper part is fixed to a crowning beam or joist. The panels are built as modules and can be adjusted for any architectural arrangement. Various window frame dimensions are possible due to this modular system. The crowning beam or joist can be made of reinforced concrete cast on site, of cold rolled steel (purlin or RT), or of timber. Together the panels create a solid wall proof against seismic shocks (cut-off walls). They are also reinforced with 40-grade rod cast in solid concrete. The continuous foundation is made of concrete cast on site with a resistance of 210 kg/cm² and a cross section of 20 x 30 cm. The housing system is patented. This means that the use of the construction system, panels and construction details is prohibited without the proprietor’s permission.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High Low X None Contractor/self-built: Contractor Self X Both Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

25





25



DESCRIPTION OF THE SYSTEM: The houses produced by hollow core concrete and other precast manufacturers in Australia can be either single storeyed or multi-level and freestanding or attached medium density. The system allows the use of both standard and non-standard components and provides an affordable solution that can be used to produce a house of high quality.

The houses are based on a panelised system of external precast concrete wall panels with lightweight non-load-bearing internal walls. Horizontal loads are transferred by diaphragm action to the perimeter walls.

Wall panels can be either full height with vertical joints or floor by floor with joints at each floor level. Wall panel configuration is dependent on the building geometry and/or fenestration. They can be supported on either pad footings or a concrete slab on ground. Where pad footings are used the walls are erected and braced prior to pouring the slab on ground.

The concrete walls can be insulated and lined internally with plasterboard. The level of insulation and method of fixing the plasterboard depends on the climate zone and the desired thermal performance. Services and installations are normally run within the insulation gap on the inside of the precast walls. Eliminating cast-in services reduces the manufacturing cost of the precast.

Precast concrete hollow core slabs are the preferred option for intermediate floors but timber can also be used.

Due to economics and simplicity of construction the roof framing is usually timber or steel supporting either tiles or metal deck roofing.

The types of houses described above are generally one-off architect designed and typically not used for low-cost housing.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry X Wet X Flooding Medium Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes X No

26




REFERENCE: Hollow Core Concrete P/L. www.hollowcore.com.au

26



DESCRIPTION OF THE SYSTEM: This system uses panels and pre-slabs. All of them are made of reinforced concrete. Every component of the system is prefabricated at a fixed plant. It consists of precast concrete panels joined by grouted connections and founded on to a cast in situ reinforced concrete slab; the floor pre-slabs are laid on to the panels a completed trough a concrete top poured out on the work site. Usual solutions for the cover can be used. The system does not allow incremental construction. Installations must be incorporated at the work site. Maximum dimensions of the panels are 0.12 m thickness, 3.00 m width and 5.00 m length, with a maximum weight of about 4300 kg. Usual number of floors is eight, allowing a maximum of twelve heights.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High X Low Both Climate: Dry X Wet X Flooding X Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes No X

27





27



DESCRIPTION OF THE SYSTEM: This system uses columns, beams and pre-slabs. All of them are made of reinforced concrete. Every component of the system is prefabricated at a fixed plant. It consists of precast concrete columns joined to a reinforced concrete in situ foundation; the beams rest and are joined to the columns; floor pre-slabs lay on to the beams and are completed trough a concrete top poured out on the work site as well as the one needed for the beam to column connection. Traditional solutions for the divisions and walls can be used. Finally the cover is solved by the same floor system described above. The system does not allow incremental construction. Installations must be incorporated at the work site. Maximum dimensions of the pre-slabs are 0.03 m thickness, 3.00 m width and 6.00 m length, with a maximum weight of about 1350 kg. Usual number of floors is four, allowing a maximum of five heights.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame X Wall Mixed High/low rise: High X Low Both Climate: Dry X Wet X Flooding X Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med X High Installations in system: Yes No X

28





28



DESCRIPTION OF THE SYSTEM: This system uses prefabrication for walls and floors. In foundations either a concrete slab is set or a frame of reinforced concrete to adapt to ground level when it has a prominent slope. Floors are made with two-directional slabs made as panels, with a depth of 0.10 m Walls are made with panels. Interior panels are solid and exterior panels are full sandwich panels. Connections between panels are arranged by means of welding plates that are inserted into both floors and panels during production. Tubes for electrical installations are also inserted during production. Normal height is two to four stories.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry Wet Flooding Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med X High Installations in system: Yes X No

29




REFERENCE: Prefabricados Castelo. www.prefabricadoscastelo.com

29



DESCRIPTION OF THE SYSTEM: This system consists of precast wall panels and hollow core slabs as flooring solutions. With only a few standardized elements, Caribbean Homes offer precast concrete solutions for affordable housing in a very high quality. The houses are based on a piling foundation with a horizontal framework. The piles can set the ground level of the houses either shortly above ground level or with a distance of about 3.0 m to offer additional space below the house. This space can be used as garage or can be used for additional living room in a later stage. For the roof construction, timber is used due to simplicity of installation. The precast concrete wall panels can include inserts and installations as usual normally only in more advanced precast concrete walling solutions. For the drilling of the holes for the piles, special machinery is required. The piles can be cast in situ, also the horizontal framework on top of the piles. An autocrane is necessary for the installation of the hollow core slabs and the wall panels. Wall panels are connected with bolts in the corners to fix and secure the system. These houses are turnkey and sold in the Caribbean for less than 40,000 USD.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry X Wet X Flooding Medium Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes X No

30




REFERENCE: Caribbean Homes, www.preconco.com

30



DESCRIPTION OF THE SYSTEM:

This system was developed to enable the construction of residential buildings with prefab structures using a set of solid concrete and hollow core slabs. This system will allow the use of a rigid central core made of solid slabs and prefab stairs, which are ready when they leave the factories.

After assembling the core on site, three other solid slabs that have structural functions are placed: two side ones and one central. Then starts the assembly of hollow core panels on the building’s facades, for a sealing function. The assembly step for these elements also serves to interlock the solid slabs.

In the next stage hollow core slabs are placed on top of the solid walls (solid slabs): first the slabs, then the panels. This sequence is repeated for each floor until the building’s prefab structure is fully assembled.

After the prefab structure has been delivered, the builder responsible for completing the construction shall perform the finishing services, such as the dry wall internal divisions, the sealing with frames and cement plates between the hollow core slabs on the façades, as well as electrical, water, fire, gas, air conditioning, painting and ceramics works, and finishing in general.

Advantages: • Quality assurance (durability, desistance, aesthetics) – Seal of excellence of Abcic

(Associação Brasileira da Construção Industrializada de Concreto) • Modular building system adaptable to the needs of the architecture proposed for each

building and compatible regarding its interface with complementary projects • Productivity (fully industrialized, the parts are produced inside the industry and assembled

on site), speed and compliance to schedules; deadline for assembling the structure: 10 days • Engineering solutions (construction details) • Sustainability (high technology, industrial system, reduction of losses, trained labour,

safety, low maintenance cost, minimal generation of residues) • Innovation (mechanization of building sites)

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry X Wet X Flooding Medium Seismic resistance: High X Low None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med High X Installations in system: Yes No X

31




REFERENCE: Cassol Pré-Fabricados www.cassol.ind.br

31



DESCRIPTION OF THE SYSTEM: This system consists of the industrialization of building by using prefab walls and reinforced concrete ceiling slabs with internal plenum.

It is used for building horizontal and vertical homes and offices and its main advantage is high productivity with increased quality and lower costs.

System components:

• Concrete slab poured on location or deep foundations depending on the type of building and the ground conditions

• Panels of prefab walls with internal plenum of a thickness that varies depending on the project

• Prefab ceiling slabs • Roof with various types of tiles • Electric and water pipe installations set inside the wall panels • Window frames and other finishes can be realised at the factory

The system can be divided into three stages:

A) Implementation of the production unit at the building site itself or in another location. B) Production and finish work on the prefab parts at the factory, including design,

manufacturing, electric and water pipe installations, setting in of the window and door frames, pre-painting, and wrapping.

C) Transportation, assembly, and final finish: transportation to the construction site where the foundations must already be ready, assembly of the part with the help of a crane depending on the size of the projects, putting on the roof, painting, final finishing work, and delivery.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry X Wet X Flooding Medium Seismic resistance: High Low None X Contractor/self-built: Contractor X Self Both Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med High X Installations in system: Yes X No

32




REFERENCE: Brasitherm Engenharia Ltda, São Paulo, Brazil

32



DESCRIPTION OF THE SYSTEM: This housing system provides innovative building solutions that include insulated-reinforced walls and structural concrete roofing components – an approach that covers from the ground up. This approach provides end-users with cost-efficient and timesaving solutions. Specifically designed with the self-builder in mind, each element can be handled by one or two persons. Elements are stacked one on top of another; a simple process that does not involve any sort of hoisting, gluing or grouting. In the end, homeowners can rely on virtually maintenance-free, lightweight concrete insulated sandwich components that guarantee total thermal and acoustic comfort. Erected on a conventional cast-in-place concrete slab using a rod-based fastening system (precast slabs can also be used), components are designed with an interlocking concept that makes erection simple; elements are assembled according to an erection plan and step-by-step instructions. Though most components are standardized, specific pieces can be designed for door and window frames, building corners and architectural elements of all kinds. Components are stacked from slab to roof, the latter of which can also be built with the system element. The system offers clear advantages, including: seismic and mechanical resistance, and water-and wind-proofing. Furthermore, the high resistance concrete practically eliminates future maintenance, and owners can choose from a wide range of colours and finishes to personalize their new homes. It provides (available in) a wide array of house plans that can be adapted to ensure full compliance with the architectural needs of the area where they will be built.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall Mixed X High/low rise: High Low X Both Climate: Dry X Wet X Flooding X Medium X Seismic resistance: High X Low None Contractor/self-built: Contractor Self Both X Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low Med High X Installations in system: Yes X No

33




REFERENCE: BPDL Precast Concrete International ¨BPDL CASA¨ www.bpdl.com

33



DESCRIPTION OF THE SYSTEM: This system consist of two slabs of concrete held together by steel trusses girders. They can be used for the production from small homes to multi-floor buildings. The system gives the building a great finish, but also allows other systems to be merged with it. The entire system is based on linkage between the concrete double walls and pre-slab lattice, either for the purpose of ceiling or floor, where mounted after the slab and the gaps between the plates of the double walls are concreted, thus forming a monolithic structure. The excellent finish and high precision of the parts are due to automated production system. The production takes place in a circular system, where a master computer controls the entire process. The forms are measured by lasers; the concrete is distributed automatically as the entire system for the concrete curing. This technology also generates a large capacity of production. Materials that provide an optimal thermal and acoustic insulation can be added to the concrete double walls. The addition of these materials can also reduce the final value of a house built with this system. Another point to be highlighted in the concrete double walls system is the possibility that the walls be supplied with electrical boxes installed, as the hydraulic items. The electrical and hydraulic lines are also installed between the concrete plates during the production process, thus avoiding the walls must be torn in the work and material be wasted.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry X Wet X Flooding Medium Seismic resistance: High X Low None Contractor/self-built: Contractor Self Both X Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med High X Installations in system: Yes X No

34




REFERENCE: Sudeste Construção Industrializada Ltda. www.sudeste.ind.br

34



DESCRIPTION OF THE SYSTEM: A precast prestressed concrete element is the heart of this new system of building. With a circular cross-section flattened from the top and bottom and a prestressed steel strand running through its centre, the element functions as a modified log of concrete that can be installed manually in between concrete columns. Mechanically produced by a slip-former, the elements are cut to variable sizes based on the requirements of each project. The distinctive shape, the method of production and the simple construction technique all combine to deliver a cost-effective solution that is up to the standards of traditional building systems. The system reduces costs and it is simple and fast to build. With a maximum span of 6 m and weight of around 10 kg per meter run, heavy machinery is not essential for construction and the light elements are easily managed by labour force. Building with this system is neither labour intensive, nor does it require skilled workers. The building technique, along with the high rate of production, makes Locrete the ideal system for housing projects with modular designs and tight timeframes. Along with its cost and time saving characteristics, the system offers environmental advantages as a result of the elimination of formwork, minimizing on-site waste and optimizing raw material utilization in production.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame X Wall Mixed High/low rise: High Low X Both Climate: Dry X Wet X Flooding Medium Seismic resistance: High Low X None Contractor/self-built: Contractor Self X Both Incremental construction: Yes X No Handling capacity: <1.5 T X <5.0 T >5T Level of technology: Low X Med High Installations in system: Yes No X

35




REFERENCE: CPI Concrete Plant International 6/2007, www.locrete.com

35



DESCRIPTION OF THE SYSTEM: The houses or apartments units produced by Precast Load Bearing Concrete Panel in Brazil can be either single storeyed or multi-level. The system consists of internal and external precast concrete wall panels with the full height.

The panels resist vertical and horizontal forces and receive the slab loads transmitting them to the slabs and foundation.

Services and installations normally run inside the precast walls, eliminating cast-in-place services that reduce the manufacturing cost.

They are supported on pad footings on the ground slabs and jointed to each other through welding bars and cast-in-place concreting.

Slabs are divided into 2 parts: precast concrete preslab and a topping in site, whereas the conduits are installed and the panels assembled.

Complements such as stairs, shafts, etc., are also precast pieces.

The assembling can be done either by cranes or tower cranes depending on the building height and the piece weight. The roof framing is usually timber or steel, supporting either tiles or metal deck roofing although the top slab can also be insulated.

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low Both X Climate: Dry X Wet X Flooding Medium Seismic resistance: High Low None X Contractor/self-built: Contractor Self Both X Incremental construction: Yes No X Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med X High Installations in system: Yes X No

36




REFERENCE: PREMO Belo Horizonte

36



DESCRIPTION OF THE SYSTEM: This system features unique designs created specifically for the Polish public sector social housing environment. It meets (and in some cases exceeds) all EU and Polish building regulations concerning social housing standards size options (apartments): • One bedroom apartment (3 rooms - M3) = 37 m2 • Two bedroom apartment (4 rooms – M4) = 60 m2 (average)

Size options (apartment blocks): • “12 unit option” = 12 units x 4 storey = 48 units (minus 1 unit for block storage)

= 47 units total • “9 unit option” = 9 units x 4 storey (minus 1unit for block storage) = 35 units total • “7 unit option” = 7 units x 4 storey (minus 1 unit for block storage) = 27 units total • “5 unit option” = 5 units x 4 storey (minus 1 unit for block storage) = 19 units total

Main characteristics: • No internal gas appliances, no lifts, no cellars • No cellars, lifts or underground parking • Flat roof (where zone plan allows) • Simplified designs – simple internal shape, simplified pipe and cable runs, wall lighting

(no ceiling lights), etc. • Simplified foundation solution

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed High/low rise: High Low X Both Climate: Dry X Wet X Flooding Medium Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T >5T X Level of technology: Low Med High X Installations in system: Yes X No

37




REFERENCE: Keriva Sp. z o.o., ul. Sobieskiego 10/2c, Kraków, Poland

37



DESCRIPTION OF THE SYSTEM: Precast concrete wall panels and columns are main components of this technology. The system has flexibility in terms of sizes and design. Columns up to 2-3 floors and wall panels up to 14’- 0’’can easily be precasted in the factory and transported to site. Most of the times columns are casted through long line method, while wall panels are casted through table moulds. Peripheral wall panels are up to 6” thick with 2” XPS or EPS insulation in it. Partition walls can be 4”or 5” depending upon design. Columns corners are chamfered for better aesthetics. As a roof element, preferably hollow core should be used. Otherwise half slabs or plain bottom slabs can be used as roof member. To make it more cost effective precast concrete girders and slabs can be used. Depending upon prices and design criteria, all services like piping and conduits can be buried with in concrete. All facilities are provided to set-up complete plant for affordable/low cost housing elements. Installation is very quick and easy. Main advantages of the system are: 1. Low capital investment 2. Easy casting 3. Fast installation 4. Aesthetics of own choice 5. Affordable cost 6. Flat roof 7. Efficient use of spaces

BASIC CHARACTERISTICS: Materials: Concrete X Steel Mixed Structural system: Frame Wall X Mixed X High/low rise: High Low X Both Climate: Dry X Wet X Flooding Medium Seismic resistance: High Low X None Contractor/self-built: Contractor X Self Both Incremental construction: Yes X No Handling capacity: <1.5 T <5.0 T X >5T Level of technology: Low Med X High Installations in system: Yes X No

38




REFERENCE: Izhar Group Lahore www.izhar.com

38




6 Bibliography [1] Serrano, Julian Salas, La industrialización posible de la vivienda latinoamericana

(Possible industrialization of Latin American housing). CYTED, 2000. [2] Building for the people. COMDEV/Mozambique. [3] Catálogo Iberoamericano de Técnicas Cosntructivas Industrializadas para Vivienda

de Interés Social. (American catalogue of constuctive techniques for social housing) CYTED. Proyecto Cyted XIV.2. 2001.

[4] Técnicas Constructivas Industrializadas para Viviendas de Bajo Costo en America

Latina. Curso Teórico Práctico. (Constructive techniques for low cost housing in Latin America, Theoretical and Practical course) Puerto Ordaz (Venezuela) 14 Oct/22 Nov 1991. CVG Funvica, IDEC, CONCIT

. [5] Tecnología para la Construcción de Venezuela ... para el mundo. (Technology of

construction in Venezuela … for the World). OTIP C.A. Oficina Técnica Ing. José A. Peña U., C.A., November 2001.

[6] World Bank, World Development Report 2000/2001: Attacking poverty

www.worldbank.org. 2001 [7] World Bank, World Development Indicators www.worldbank.org/poverty/

wdrpoverty, 2005. [8] Campos, P. E., Industrialização da construção e argamassa armada; perpectivas de

desenvolvimento. (Industrialization of constructions in reinforced mortar) São Paulo, EPUSP, 1989.

[9] CEPAL (Comisión Económica para América Latina y el Caribe – Economic

commision for Latin America and the Carribean), Panorama social de América Latina. Santiago de Chile, June 1994.

[10] CEPAL, Alojar el Desarrollo: Una tarea para los asentamientos humanos. (Host the

development: a task for human settlements) Documento LC/L906. CONF.85/3. Ver Actas de la Reunión CYTED: Iberoamérica ante Hábitat II. Ministerio de Fomento, Madrid, 1996.

[11] COHRE (Centre on Housing Rights and Evictions), Forced Eviction Violations of

Human Rights. Gobal Survey nº8, Ginebra Suiza, 2002. [12] COHRE, Gobal Survey nº8, Ginebra Suiza, 2003. [13] Filgueira J., La obra de Joao Filgueiras Lima, Lelé (The works of Joao Filgueiras

Lima, Lele). Recopilación del Inst. Lina Bo Bardi, Edit. Gustavo Gili, Blau. Barcelona 2003.

[14] CYTED, Constructivas Industrializadas para Vivienda de Interés Social (Industrial

constructions for Social Housing). Uruguay, Montevideo.


122 6 Bibliography

[15] Mac Donald J., Pobres en ciudades pobres (Poor people in poor cities). I Congreso Internacional sobre Desarrollo Humano, Ayuntamiento de Madrid, November 2006.

[16] ONUDI, First Consultation on Bulding Material, Atenas, March 1985. [17] Salas, J., Respuestas a la Primera Consulta sobre la industria de los Materiales de

Construcción de ONUDI. Materiales de Construcción, Vol. 35, nº 198, pp. 15/ 30, Madrid, June 1985.

[18] Salas J., Contra el Hambre de Vivienda. Soluciones tecnológicas latinoamericanas

(Against hunger in housing. Technological solutions). Edit. Escala, Bogotá, Colombia, 1993.

[19] Salas J., La industrialización ‘posible’ de la vivienda latinoamericana. (Possible

industrialization for Latin American Housing). Edit. ESCALA, Bogotá, Combia, 1997.

[20] Salas J., Colavidas F., Oteiza I., 2007, Hacia una manualistica universal de

componentes para el mejoramiento barrial (Towards a universal components manual for better neighbourhods). Edit. Mairea, ETSAM – UPM, Madrid, 2007.

[21] UNESCO, Mayor Zaragoza: UNESCO ante Hábitat II, Estambul, Turquia, 1996. [22] UN HABITAT, United Nations Centre for Human Settlements (Hábitat): Informe

Mundial sobre los Asentamientos Humanos, 1996. [23] UN HABITAT, Improving the lives of 100 million slum dwellers. Global Observatory,

UN HABITAT, Nairobi, 2003. [24] UN HABITAT, The challenge of slums. Global Report on Human Settlements,

Nairobi, 2003. [25] UN HABITAT, Declaración de Nueva Delhi (New Delhi Declaration), 27.06.2007.

Ver El País, August 2007. [26] WACLA, World Assembly of Cities and Local Authorities: Soluciones locales y

problemas globales: El futuro de los asentamientos humanos. Istanbul, May 1996. [27] Benavides, C. A., Tecnología, innovación y empresa (Technology, innovation and

companies). Ediciones Pirámide, 1998.

[28] Koehn, E. and Soni, M., Prefabricated housing in developing countries: India. Creative Systems in Structural and Construction Engineering, Edited by Singh, pp. 57-61, 2001.

[29] Marcaccioli, L. and Menegotto, M., Low-cost Houses for Self-construction with Precast Wall Panels. Role of Structructural Engineers towards Reduction of Poverty, IABSE, pp. 243 – 250. 2005.

[30] FIP, Planning and Design Handbook on Precast Building Structures, 1994.



[31] Elliot, Kim S., Precast Concrete Structures, Butteworth – Heinemann, 2005. [32] Van Acker, A., “Lectures on Prefabrication”, CONSOLIS - Technology edition, 2005.

[33] Cleland, N. and Ghosh, S.K., “Seismic Design of Precast/Prestressed Concrete

Structures”, PCI MNL 140. First edition, 2007. [34] PCI, Design Handbook, Precast and Prestressed Concrete. 6th edition, 2004.

[35] Koncz, Handbuch Der Fertigteilbauweise, Band 2, Bauverlag GmbH Wiesbaden und

Berlin, 1967. [36] Koncz, Handbuch Der Fertigteilbauweise, Band 3, Bauverlag GmbH Wiesbaden und

Berlin, 1974. [37] Bindeseil, Stahlbeton-Fertigteile, Konstruktion – Berechnung – Ausführung, 3

Auflage, Werner Verlag, 2007. [38] SysproPART, Die Technik zur Wand, Wie wird’s gemacht? 1997.

[39] Assobeton, Enrico Dassori, “La prefabbricazione in calcestruzzo – Guida all’ utilizzo

nella progettazione”. BE-MA Editrice, 2001. [40] Eurocodes 2 and 8.

[41] fib Bulletin 27, “Seismic design of precast concrete building structures”, 2004. [42] Internal report of the ongoing work of fib Task Group 6.10, 2010 (available from the

Task Group). [43] Green Affordable Housing Coalition, Insulation & Air Sealing, Fact Sheet No. 8,

2004. [44] Corsellis and Vitale, Transitional settlement displaced populations, University of

Cambridge – OXFAM, 2005.



fib – fédération internationale du béton – the International Federation for Structural Concrete – is grateful for the invaluable support of the following National Member Groups and Sponsoring Members, which contributes to the publication of fib technical bulletins, the Structural Concrete Journal, and fib-news.

National Member Groups AAHES – Asociación Argentina del Hormigón Estructural, Argentina CIA – Concrete Institute of Australia ÖVBB – Österr. Vereinigung Für Beton und Bautechnik, Austria Belarussian Nat. Techn. University GBB – Groupement Belge du Béton, Belgium ABCIC – Associação Brasileira da Construção Industrializada de Concreto, Brazil ABECE – Associação Brasileira de Engenharia e Consultoria Estrutural, Brazil fib Group of Canada CCES – China Civil Engineering Society Hrvatska Ogranak fib-a (HOFIB) – Croatian Group of fib Cyprus University of Technology Ceska betonarska spolecnost, Czech Republic Dansk Betonforening DBF – Danish Concrete Society Suomen Betoniyhdistys r.y. – Concrete Association of Finland AFGC – Association Française de Génie Civil, France Deutscher Ausschuss für Stahlbeton, Germany Deutscher Beton- und Bautechnik-Verein e.V. – dbv, Germany FDB – Fachvereinigung Deutscher Betonfertigteilbau e.V., Germany Technical Chamber of Greece Hungarian Group of fib, Budapest University of Technology & Economics The Institution of Engineers (India) Technical Executive (Nezam Fanni) Bureau, Iran IACIE – Israeli Association of Construction and Infrastructure Engineers Consiglio Nazionale delle Ricerche, Italy JCI – Japan Concrete Institute PCEA – Prestressed Concrete Engineering Association, Japan Administration des Ponts et Chaussées, Luxembourg Betonvereniging – fib Netherlands New Zealand Concrete Society Norsk Betongforening – Norwegian Concrete Association Polish Academy of Sciences Committee of Civil Engineering, Silesian Technical University, Poland GPBE – Grupo Portugês de Betão Estrutural, Portugal Society For Concrete and Prefabricated Units of Romania Technical University of Civil Engineering, Romania Association for Structural Concrete (ASC), Russia


Association of Structural Engineers, Serbia Slovak Union of Civil Engineers Slovenian Society of Structural Engineers ACHE – Asociacion Cientifico-Técnica del Hormigon Estructural, Spain Svenska Betongföreningen, Sweden Délégation nationale suisse de la fib, EPFL, Switzerland ITU – Istanbul Technical University, Turkey Research Institute of Build. Constructions, Ukraine fib UK Group ASBI – American Segmental Bridge Institute, USA PCI – Precast/Prestressed Concrete Institute, USA PTI – Post Tensioning Institute, USA Sponsoring Members Preconco Limited, Barbados Liuzhou OVM Machinery Co., Ltd , China Consolis TECHNOLOGY Oy Ab, Finland FBF Betondienst GmbH, Germany FIREP Rebar Technology GmbH, Germany MKT Metall-Kunststoff-Technik GmbH, Germany Verein zur Förderung und Entwicklung der Befestigungs-, Bewehrungs- und

Fassadentechnik e. V. – VBBF, Germany Larsen & Toubro Ltd ECC Division, India Sireg S.P.A., Italy Fuji P. S. Corporation Ltd., Japan Obayashi Corporation, Japan Oriental Shiraishi Corporation, Japan P.S. Mitsubishi Construction Co., Ltd, Japan PC BRIDGE Company Ltd., Japan SE Corporation, Japan Sumitomo Mitsui Construct. Co.Ltd., Japan BBR VT International Ltd., Switzerland SIKA Services AG, Switzerland VSL International Ltd , Switzerland China Engineering Consultants, Inc, Taiwan (China) PBL Group Ltd, Thailand CCL Stressing Systems Ltd, United Kingdom Strongforce Engineering PLC, United Kingdom


fib Bulletins published since 1998

N° Title 1 Structural Concrete – Textbook on Behaviour, Design and Performance;

Vol. 1: Introduction - Design Process – Materials Manual - textbook (244 pages, ISBN 978-2-88394-041-3, July 1999)

2 Structural Concrete – Textbook on Behaviour, Design and Performance Vol. 2: Basis of Design Manual - textbook (324 pages, ISBN 978-2-88394-042-0, July 1999)

3 Structural Concrete – Textbook on Behaviour, Design and Performance Vol. 3: Durability - Design for Fire Resistance - Member Design - Maintenance, Assessment and Repair - Practical aspects Manual - textbook (292 pages, ISBN 978-2-88394-043-7, December 1999)

4 Lightweight aggregate concrete: Extracts from codes and standards State-of-the-art report (46 pages, ISBN 978-2-88394-044-4, August 1999)

5 Protective systems against hazards: Nature and extent of the problem Technical report (64 pages, ISBN 978-2-88394-045-1, October 1999)

6 Special design considerations for precast prestressed hollow core floors Guide to good practice (180 pages, ISBN 978-2-88394-046-8, January 2000)

7 Corrugated plastic ducts for internal bonded post-tensioning Technical report (50 pages, ISBN 978-2-88394-047-5, January 2000)

8 Lightweight aggregate concrete: Part 1 (guide) – Recommended extensions to Model Code 90; Part 2 (technical report) – Identification of research needs; Part 3 (state-of-art report) – Application of lightweight aggregate concrete (118 pages, ISBN 978-2-88394-048-2, May 2000)

9 Guidance for good bridge design: Part 1 – Introduction, Part 2 – Design and construction aspects. Guide to good practice (190 pages, ISBN 978-2-88394-049-9, July 2000)

10 Bond of reinforcement in concrete State-of-art report (434 pages, ISBN 978-2-88394-050-5, August 2000)

11 Factory applied corrosion protection of prestressing steel State-of-art report (20 pages, ISBN 978-2-88394-051-2, January 2001)

12 Punching of structural concrete slabs Technical report (314 pages, ISBN 978-2-88394-052-9, August 2001)

13 Nuclear containments State-of-art report (130 pages, 1 CD, ISBN 978-2-88394-053-6, September 2001)

14 Externally bonded FRP reinforcement for RC structures Technical report (138 pages, ISBN 978-2-88394-054-3, October 2001)

15 Durability of post-tensioning tendons Technical report (284 pages, ISBN 978-2-88394-055-0, November 2001)

16 Design Examples for the 1996 FIP recommendations Practical design of structural concrete Technical report (198 pages, ISBN 978-2-88394-056-7, January 2002)


N° Title 17 Management, maintenance and strengthening of concrete structures

Technical report (180 pages, ISBN 978-2-88394-057-4, April 2002)

18 Recycling of offshore concrete structures State-of-art report (33 pages, ISBN 978-2-88394-058-1, April 2002)

19 Precast concrete in mixed construction State-of-art report (68 pages, ISBN 978-2-88394-059-8, April 2002)

20 Grouting of tendons in prestressed concrete Guide to good practice (52 pages, ISBN 978-2-88394-060-4, July 2002)

21 Environmental issues in prefabrication State-of-art report (56 pages, ISBN 978-2-88394-061-1, March 2003)

22 Monitoring and safety evaluation of existing concrete structures State-of-art report (304 pages, ISBN 978-2-88394-062-8, May 2003)

23 Environmental effects of concrete State-of-art report (68 pages, ISBN 978-2-88394-063-5, June 2003)

24 Seismic assessment and retrofit of reinforced concrete buildings State-of-art report (312 pages, ISBN 978-2-88394-064-2, August 2003)

25 Displacement-based seismic design of reinforced concrete buildings State-of-art report (196 pages, ISBN 978-2-88394-065-9, August 2003)

26 Influence of material and processing on stress corrosion cracking of prestressing steel – case studies. Technical report (44 pages, ISBN 978-2-88394-066-6, October 2003)

27 Seismic design of precast concrete building structures State-of-art report (262 pages, ISBN 978-2-88394-067-3, January 2004)

28 Environmental design State-of-art report (86 pages, ISBN 978-2-88394-068-0, February 2004)

29 Precast concrete bridges State-of-art report (83 pages, ISBN 978-2-88394-069-7, November 2004)

30 Acceptance of stay cable systems using prestressing steels Recommendation (80 pages, ISBN 978-2-88394-070-3, January 2005)

31 Post-tensioning in buildings Technical report (116 pages, ISBN 978-2-88394-071-0, February 2005)

32 Guidelines for the design of footbridges Guide to good practice (160 pages, ISBN 978-2-88394-072-7, November 2005)

33 Durability of post-tensioning tendons Recommendation (74 pages, ISBN 978-2-88394-073-4, December 2005)

34 Model Code for Service Life Design Model Code (116 pages, ISBN 978-2-88394-074-1, February 2006)

35 Retrofitting of concrete structures by externally bonded FRPs. Technical Report (224 pages, ISBN 978-2-88394-075-8, April 2006)


N° Title 36 2006 fib Awards for Outstanding Concrete Structures

Bulletin (40 pages, ISBN 978-2-88394-076-5, May 2006)

37 Precast concrete railway track systems State-of-art report (38 pages, ISBN 978-2-88394-077-2, September 2006)

38 Fire design of concrete structures – materials, structures and modelling State-of-art report (106 pages, ISBN 978-2-88394-078-9, April 2007)

39 Seismic bridge design and retrofit – structural solutions State-of-art report (300 pages, ISBN 978-2-88394-079-6, May 2007)

40 FRP reinforcement in RC structures Technical report (160 pages, ISBN 978-2-88394-080-2, September 2007)

41 Treatment of imperfections in precast structural elements State-of-art report (74 pages, ISBN 978-2-88394-081-9, November 2007)

42 Constitutive modelling of high strength / high performance concrete State-of-art report (130 pages, ISBN 978-2-88394-082-6, January 2008)

43 Structural connections for precast concrete buildings Guide to good practice (370 pages, ISBN 978-2-88394-083-3, February 2008)

44 Concrete structure management: Guide to ownership and good practice Guide to good practice (208 pages, ISBN 978-2-88394-084-0, February 2008)

45 Practitioners’ guide to finite element modelling of reinforced concrete structures State-of-art report (344 pages, ISBN 978-2-88394-085-7, June 2008)

46 Fire design of concrete structures —structural behaviour and assessment State-of-art report (214 pages, ISBN 978-2-88394-086-4, July 2008)

47 Environmental design of concrete structures – general principles Technical report (48 pages, ISBN 978-2-88394-087-1, August 2008)

48 Formwork and falsework for heavy construction Guide to good practice (96 pages, ISBN 978-2-88394-088-8, January 2009)

49 Corrosion protection for reinforcing steels Technical report (122 pages, ISBN 978-2-88394-089-5, February 2009)

50 Concrete structures for oil and gas fields in hostile marine environments State-of-art report (36 pages, IBSN 978-2-88394-090-1, October 2009)

51 Structural Concrete – Textbook on behaviour, design and performance, vol. 1 Manual – textbook (304 pages, ISBN 978-2-88394-091-8, November 2009)

52 Structural Concrete – Textbook on behaviour, design and performance, vol. 2 Manual – textbook (350 pages, ISBN 978-2-88394-092-5, January 2010)

53 Structural Concrete – Textbook on behaviour, design and performance, vol. 3 Manual – textbook (390 pages, ISBN 978-2-88394-093-2, December 2009)

54 Structural Concrete – Textbook on behaviour, design and performance, vol. 4 Manual – textbook (196 pages, , ISBN 978-2-88394-094-9, October 2010)

55 fib Model Code 2010, First complete draft – Volume 1 Draft Model Code (318 pages, ISBN 978-2-88394-095-6, March 2010)


N° Title 56 fib Model Code 2010, First complete draft – Volume 2

Draft Model Code (312 pages, ISBN 978-2-88394-096-3, April 2010)

57 Shear and punching shear in RC and FRC elements. Workshop proceedings. Technical report (268 pages, ISBN 978-2-88394-097-0, October 2010)

58 Design of anchorages in concrete Guide to good practice (282 pages, ISBN 978-2-88394-098-7, July 2011)

59 Condition control and assessment of reinforced concrete structures exposed to corrosive environments (carbonation/chlorides) State-of-art report (80 pages, ISBN 978-2-88394-099-4, May 2011)

60 Prefabrication for affordable housing State-of-art report (132 pages, ISBN 978-2-88394-099-4, May 2011)

Abstracts for fib Bulletins, lists of available CEB Bulletins and FIP Reports, and an order form are available on the fib website at www.fib-international.org/publications.


fib_Bulletin_60.pdf - AFGC

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