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Technical Report No. Vol: 01/Bib/Civil/DrMGRU/2012
BIBLIOGRAPHY ON MASONRY STRUCTURES-TECHNICAL REPORT
PROF. S.SAILEYSH SIVARAJA
PROF.S.MOSES ARANGANATHAN &
PROF.T.S.THANDAVAMOORTHY
Reference for M.Tech (Struct) & PhD Scholars
DEPARTMENT OF CIVIL ENGINEERING, Dr. M.G.R Educational and
Research Institute University, Maduravayal, Chennai-600 095, Tamil
Nadu, India E Mail: [email protected] &
[email protected]
May 2012
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ABSTRACT: Considering the slow development in the research
relating to masonry structures and to give an impetus and
accelerate this annotated bibliography has been prepared by
reviewing the available literature. This bibliography presents
various aspects of research on masonry structures.
TABLE OF CONTENTS
CHAPTER No. TITLE. PAGE No.
1.0 INTRODUCTION 2
An exhaustive bibliography is of masonry structures namely
bricks, mortars, cement, reinforced cement concrete, Fiber
Reinforced Concrete, Polymer Concrete and construction, etc, has
become a necessity to accelerate the research on this topics;
Literature relating to these various aspects have been reviewed and
compiled as a report here.
The following topics have been dealt with herein:
(i)Structural Brickwork
(ii) Materials Properties
(iii) Testing
(iv) Analysis and Design
(v) Dynamic Loading and Responses
(vi) Seismic Behaviour
(vii) Case Studies
(viii) Retrofitting.
The chapters on Case studies have been included to throw light
on Applications aspects. Finally the chapter on Retrofitting
highlights the use of different masonry system in Repair and
Rehabilitation process.
The objective of this bibliographic collection is to bring under
one roof all information about various masonry systems and masonry
components available in open literature. Such an exercise has been
necessitated as no such documents is available as at present. It is
hoped that this work would serve as a useful guide for future
research in the area of masonry and all aspects relating
thereto.
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TABLE OF CONTENTS
CHAPTER No. TITLE. PAGE No.
2.0 STRUCTURAL BRICKWORK 04
3.0 MATERIALS PROPERTIES 07
4.0 TESTING 12
5.0 ANALYSIS AND DESIGN 25
6.0 DYNAMIC LOADING AND RESPONSES 37
7.0 SEISMIC BEHAVIOUR 46
8.0 CASE STUDIES 72
9.0 RETROFITTING 81
10.0 SUMMARY 105
11.0 REFERENCES 105
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2.0 STRUCTURAL BRICKWORK
2.1) Thomas, K., Structural Brickwork-Materials and Performance,
The Structural Engineer, 1971, Vol.49, No.10, pp.441-450.
Calculated load bearing brickwork is discussed and the basic
requirements are specified materials and their effects on strength
and performance are considered and recommendations made. The
mechanism of brickwork failure under vertical and lateral loading
is covered and the results of current research in this field are
included. Factors affecting strength are discussed and information
is provided on composite action with concrete beams, also quality
control.
2.2) Alani, A.F., EL-Katib,M.T., Ovanessian, R.A and Korkees,
I.N., Structural Elevation of Load Bearing Brick Cavity Walls with
Brick Ties, Journal of Structural Engineering, 1989, Vol.16, No.3.,
pp.85-93.
This research work forms a part of a project to investigate the
structural behaviour of load bearing double wythes cavity walls
built using local material and workmanship. This investigation was
made using a full scale one storey height walls with brick units
acting as connectors across a 50 mm cavity. The walls were
subjected to both concentric and eccentric vertical loads up to
failure. The eccentricity to thickness ratios ranged from 0.0 to
0.30. Twelve specimens were tested. They were divided in to three
groups depending up on the type of mortar, cement: sand (1:3),
Cement: lime: sand (1:1:6), and gypsum mortar (locally known as
Juss mortar).Based on experimental results an empirical equation is
produced to calculate the ultimate strength of storey height brick
cavity walls. The theoretical results compared quite well with the
test results. Comparison of results with various international
design codes showed good agreement with CP111-Part 2 while both the
Canadian and UBC codes show diverge results.
2.3) Toranzo, L.A., Carr, A.J and Restrepo, J.I., Improvement of
Traditional Masonry Wall Construction for Use in Low Rise or Low
Wall Density Building in Seismically Prone Regions, Proceeding of
NZSEE Conference, 2001, pp.1/1-5/5.
The current trend of designing structures to meet performance
based demands could severely limit the use of some traditional
construction materials and systems. Masonry construction used in
conjunction with reinforced frames, as used extensively in Latin
America is among those affected. This limitation is due to the poor
performance of conventional masonry system is earthquakes. This
paper discusses the option of using reinforced concrete frames
in-filled with masonry, acting together as a series of rocking
walls providing a desired performance level. Such system may be
used in buildings with a low density of elements where the demand
expected in conventionally built masonry walls might result in
structural damage in moderate earthquake. Rocking walls can be
designed to rock while ensuring no damage will occur anywhere else
in the structures. During the rocking process the system has a much
lower equivalent stiffness than before rocking in triggered. Most
often this means that the inertial forces are reduced as the
response is shifted in to a less demanding region of the
acceleration spectra. The softening of the system also lets other
flexible elements participate in the response. Triggering of the
rocking may be
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set for levels of excitation greater than frequent earthquakes
for which the element can be designed to behave as a fixed base
wall. Rocking also allows the use of hysteretic energy dissipaters
at the base of the wall. It was found that these energy dissipaters
could add up to 20% of equivalent viscous damping to the
system.
2.4) Sarangapani, G., Venkatarama Reddy, B.V and Jagadish, K.S.,
Structural Characteristics of Bricks, Mortars and Masonry, Journal
of Structural Engineering, Vol.29, No.2, 2002, pp.101-109.
Burnt clay bricks are widely used load bearing masonry in India.
There is wide variation in the characteristics of commonly used
bricks from different geographical locations of the country. For
example the compressive strength vary between 2 and 24 Mpa. This
paper deals with the characteristics of properties of local low
modulus bricks, mortars and masonry using these materials. Bricks
procured from Bangalore were tested for obtaining the properties
such as compressive strength, flexure strength, water absorption,
Initial Rate of Absorption (IRA), porosity and pore size and
stress-strain relationships. Characteristics of two cement mortars
(1:4 and 1:6) and three composite mortars (cement soil and cement
lime mortars) were examined for their strength and elastic
properties. Stress-strain characteristics of masonry using these
bricks and mortars were determined. A simple analysis was carried
out to understand the nature of stresses developed in the mortar
joint and brick in the masonry. The results reveal that the bricks
around Bangalore have rather low module compared to cement mortar.
The brick modulus is in the range of about 5 to 10 % of the modulus
of 1:6 cement mortar.This kind of situation leads to a masonry were
mortar joints develop lateral tension while brick develops lateral
compression (tri-axial) and this is an unfavorable situation due to
the brittle nature of mortar.
2.5) Punmia, B.C., Asok Kumar Jain and Arun Kumar Jain, A Text
Book of Building Construction, Lakmi Publications (P) Limited, New
Delhi, India, 2006.
Man requires different types of buildings for his activities:
houses, bungalows and flats for living; hospitals and health
centers for his health; school colleges and universities for his
education; banks, shops, offices, buildings and factories for doing
work; railway buildings, bus stations and air terminals for
transportation; clubs, theatres and cinema houses for re-creation
and temples, mosques, churches, darmashalas etc, for worship. Each
type of the above buildings has its own requirements. The above
building activities are an important indicator of the countrys
social progress.
2.6) Ana Radivojevi and Nadja Kurtovi-Foli, Evolution Of Bricks
And Brick Masonry In The Early History Of Its Use In The Region Of
Todays Serbia, Journal of Materials in Civil Engineering, 2006,
Vol. 18, No. 5, October 1, pp692699
Brick was proved to be one of the main building materials in the
region of todays Serbia, especially in the time of late antiquity
and in the following medieval time. Hence, the idea was born to
make a comparison between the main characteristics of late antique
and medieval bricks and brickworks from this region that could
confirm the continuity and variety of its use. A question of
evolution of the use of bricks was partly based on comparison of
their estimated properties and also on comparison of applied
building techniques and known characteristics of brick production.
It has been
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confirmed that although it is possible to discuss and confirm
the continuity in the use of bricks and adequate building
techniques, up-to-date research based on quantitative analysis of
historical bricks do not offer enough comparable data regarding
their quality. There-fore a new field of possible qualitative
research is needed in the future.
2.7) Manjunath.S, Renuka Devi. M and K.S.Jagadish, Strength Of
Hollow Block Masonry Walls, 2009-10, Research Centre : R.V.College
of Engineering, India.
Masonry has been used as a basic construction material for
public and residential buildings in the past several thousand
years; from the tower of Babylon ,to the great wall of china, which
is the only man made structure visible from the moon. A number of
well preserved old masonry building still exist, proving that
masonry can successfully resist loads and environmental impacts,
therefore providing shelter for people and their goods for a long
period of time, if adequately conceived and constructed. Although
some specific features have been invented during the course of time
to improve the seismic behavior of masonry buildings , such as
connecting stones, strengthening of the corners and wall
intersection zones, as well as tying of the walls even today,
masonry construction represents the most vulnerable part of
existing building. This is not only in the case of developing or
underdeveloped countries but it is also in the case of some of the
developed countries of Europe and the USA.
2.8) Maria P. Durante Ingunza, Anaxsandra C. L. Duarte and
Rubens M. Nascimento, Use Of Sewage Sludge As Raw Material In The
Manufacture Of Soft-Mud Bricks, Journal of Materials in Civil
Engineering, 2011, Vol. 23, No. 6, June-1, pp852856
This article assesses the use of sewage sludge as a raw material
in the ceramic industry, specifically in the manufacture of
soft-mud bricks, to determine the maximum incorporation of sludge
that results in technically sound and environmentally friendly
bricks. The results obtained confirm that there was no alteration
in the odor of the bricks, even at high proportions of sludge;
however, high concentrations of sludge had a negative influence on
certain properties, such as mechanical strength and absorption.
Compressive strength was significantly diminished with the addition
of sludge: the bricks with 5% sludge lost an average of 45% of the
strength obtained by the control brick; the bricks manufactured
with 15 and 20% lost around 70% of maximum strength; however, they
still met minimum strength standards. For the specified conditions
of this study, it was concluded that 20% was the maximum proportion
of sludge that could be incorporated into a ceramic mass and still
meet technical and environmental requirements.
2.9) Jianhai Liang and Ali M. Memari, M.ASCE, Introduction Of A
Panelized Brick Veneer Wall System And Its Building Science
Evaluation, Journal of Architectural Engineering, 2011, Vol. 17,
No. 1, March 1, pp114
This paper introduces a panelized brick veneer over steel stud
backup wall system to address some of the shortcomings of
conventional systems. Thermal and hydrothermal analyses of the
proposed wall system with different stud gauges and arrangements
are discussed. The movement joint design aspects, a pressure
moderation performance evaluation, the simulated wind-driven water
penetration results, and an example cost analysis are also
presented. This study provides information about some of the
attributes of the proposed system such as crack
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resistance and water penetration potential as well as the
pressure moderation aspect. Some of the issues that need
consideration for the practical application of the system are also
described.
3.0 MATERIAL PROPERTIES:
3.1) Krishna Naraine and Sachchidanand Sinha, Loading And
Unloading Stress-Strain Curves For Brick Masonry, Journal of
Structural Engineering, 1989, Vol. 115, No. 10, pp2631-2644
Reloading and unloading stress-strain curves of brick masonry
tested under uniaxial cyclic compressive loadings perpendicular and
parallel to the bed joint are discussed. A simple mathematical
model is proposed to predict these curves at different values of
plastic strain. An exponential relationship involving the axial
stress, the axial strain, and the plastic (residual) strain is
found to be appropriate to represent the reloading and unloading
curves. It is shown that the reloading curves can be mathematically
represented by a family of parabolas and the unloading curves can
be similarly represented by a family of straight lines. The
equations of a parent parabola and a parent straight line are used
to generate the family of parabolas and the family of straight
lines respectively. The families of parabolas and straight lines
can then be used to compute the reloading and unloading curves
respectively. Comparisons of the model predictions with the
experimental reloading and unloading curves show very good
agreement.
3.2) Deodhar, S.V and Patel, A.N., Behaviour of Brick Masonry in
Compression, Journal of Structural Engineering, 1996, Vol.22, No.4,
pp.221-224.
Brick masonry has been used from time immemorial for
construction of low- rise residential buildings and columns etc.,
to resist compressive loads. The strength of masonry depends on the
strength of brick, mortar and adhesion between the two, joint
thickness and various other factors. Thus for the same type of
brick, using same proportion of cement and sand, the strength
obtained may differ to due to variation in quantity of water,
difference in workshop, arrangement of bricks and many other
reasons. Under the compressive load, mortar deforms laterally and
squeezes out causing cracks at joints. Some additives in mortar
increase the adhesion at the brick faces, increasing the strength.
However clay content in sand decreases the adhesion, and
consequently the strength of masonry. The other factor that affects
the strength is joint thickness. The adhesion between brick and
mortar depends upon the effective. Transfer to matrix between these
two materials, which in turn depends upon appropriate thickness of
mortar joint used for bonding the bricks. The size of brick is also
one of the important factors that may affect the strength of brick
masonry. The brick that was commonly used in early 1960's was quite
thin (25 to30mm) whereas present practice is to use thicker bricks.
Large brick size reduces number of mortar joints which are the weak
parts in masonry. Minimization of mortar joins is likely to
increase the strength and makes masonry more economical and reduces
the overall cost of construction. Frog plays an important role in
bonding the brick work. Shape and size of frog may affect the
strength of brick masonry to certain extent. It is presumed that
rendering over masonry is incorporated to prevent the effect of
atmospheric agencies on brick masonry. However if masonry is raked
at
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the joints and rendering is provided, there is every possibility
of increasing the load carrying capacity of brick masonry. With all
these parameters in mind an experimental programme was undertaken
to study the effect of these parameter on crushing strength of
masonry and conclusions are reported.
3.3) Deodhar, S.V and Patel, A.N., Strength Relationship of
Brick Masonry Brick and Cement Mortar, Journal of Structural
Engineering, 1997, Vol.23, No.4, pp.215-218.
Brick and brick masonry have been used extensively in building
construction for many centuries and continues to dominate as the
commonly used construction material either as a load bearing or as
a filler wall. It is further well established that if good quality
bricks having crushing strength more than 10.50 N/mm2 are bonded in
1:3 cement-sand mortar for ground and first floor and in 1:6 cement
mortar for third and fourth floor, a four storied building can be
constructed with 225 mm thick brick wall, using conventional
brick.
3.4) Jagadish, K.S., Basic Structural Properties of Masonry,
Proceeding of the Workshop on Recent Advances in Masonry
Construction, Rookie, India., 1998., pp.41-52.
Use of brick masonry has been known, especially in India, for
nearly 5000 years. Even in other countries brick masonry has been
in use for more than thousand years. However, the earliest recent
material like concrete has received far greater attention by the
Civil Engineer. For instance, research papers on concrete are found
as early as in 1907. However, the earliest report on brick masonry
was produced in 1918. The paucity literature in the Indian context
is also striking, in spite of the fact that a few sporadic attempts
were made to study brick masonry since the mid sixties. The problem
of brick masonry in India is compounded by the fact that bricks and
mortars vary widely in character in different regions. The
situation is very different from that of concrete.
3.5) Milad m. Alshebani and s. N. Sinha, Stress-Strain
Characteristics Of Brick Masonry Under Uniaxial Cyclic Loading,
Journal of structural engineering, 1999, vol.125, no.6,
pp600-604
A series of laboratory tests were carried out on half-scale sand
plast brickwork panels subjected to uniaxial cycle loading.
Forty-two square panels were tested under cycle loading until
failure for two cases of loading: (1) Normal to the bed joint; and
(2) parallel to the bed joint. Failure due to cyclic compressions
was usually characterized by a simultaneous failure of brick units
and head joints or by splitting in the bed joints depending on
whether the panel was loaded normal or parallel to the bed joint,
respectively. The characteristics of the stress-strain relationship
of the two loading conditions are presented in this paper.
Envelope, common point, and stability point stress-strain curves
were established based on test data, and an exponential formula was
found to provide a reasonable fit to the test data. It was
concluded that the peak stress of the stability point curve can be
regarded as the maximum permissible stress level that is found to
be approximately equal to two thirds of the failure stress. It was
also observed that the permissible stress level depends on the
plastic strain level present in the material due to cyclic
loading.
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3.6) F. M. Khalaf and a. S. Devenny, New Tests For Porosity And
Water Absorption Of Fired Clay Bricks, Journal Of Materials In
Civil Engineering, 2002, Vol. 14, no. 4, august 1, pp334-337
The porosity of bricks, and their permeability and absorption
are very important factors in influencing properties of bricks such
as the bond between them and mortar, the resistance of bricks to
freezing and thawing, and their chemical stability. This paper
suggests new tests for calculating the porosity and water
absorption values of clay bricks, which involve the testing of
20-mm brick lumps instead of full brick units.
3.7) Asteris, P.G., Lateral Stiffness of Brick Masonry In-Filled
Plane Frames, Discussion and closures, Journal of Structural
Engineering, 2003, Vol.129, No.8, pp.1071-1079.
The author investigates the lateral stiffness of in-filled
frames, particularly focusing on the reduction of stiffness due to
opening. The finite element method is used to analyze various
configuration. Infill behaviour in itself is quite complex and
openings add to the complexity of the problem. Thus the author is
to be commended for examining problem.
3.8) Bryan D. Ewing and Mervyn J. Kowalsky, Compressive Behavior
Of Unconfined And Confined Clay Brick Masonry, Journal of
Structural Engineering, 2004, Vol. 130, No. 4, April 1,
pp650-661
Presented in this paper are the results of an investigation of
the compressive behavior of grouted clay brick masonry prisms. The
objective is to experimentally capture the stressstrain
characteristics of unconfined and confined clay brick masonry and
compare the response with that predicted with the modified KentPark
stressstrain curve. Based on the experimental results, five limit
states for clay brick masonry in compression are proposed, as well
as equivalent stress blocks for design. Thin galvanized steel
plates placed in the mortar joints during construction provided
prism confinement. The variables considered included volumetric
ratio of confining steel ~0, ;0.015, and ;0.03! and the presence of
machined holes within the confinement plates to improve the bond
between the masonry and steel plate. It is shown that confinement
plates are extremely effective in enhancing the ultimate
compressive strength as well as increasing the deformation capacity
of the clay brick masonry prisms. The use of confinement plates in
the test increased the ultimate compression strength by 40%.
Failure of the confined masonry prisms occurred simultaneously or
immediately after yielding of the confinement plates.
Experimentally obtained stressstrain curves agreed reasonably well
with the modified KentPark model.
3.9) Peter J. Walker, Strength And Erosion Characteristics Of
Earth Blocks And Earth Block Masonry, Journal of Materials in Civil
Engineering, 2004, Vol. 16, No. 5, pp497-506
The paper describes methods currently used for strength and
erosion resistance testing of earth blocks. Following this, an
experimental study undertaken to assess the
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influence of test procedure and specimen geometry on strength
and erosion characteristics is presented. Cement stabilized pressed
earth blocks were fabricated using different blended soils and
compacted using a constant volume manual press. The effects of
specimen geometry on experimental compressive strength are
described and aspect ratio correction factors for unconfined unit
strength outlined. Proposals for a unified approach to compression
strength testing are also suggested. Bending strength testing is
commonly used as an indirect method of strength assessment, as it
is more readily suited to in-situ quality control testing than
compression testing. The experimental correlation between
compressive and bending strengths is presented. Results of
compression tests on masonry walls are also presented together
recommendations for design. Finally, the influence of test method
and specimen geometry on erosion resistance and the correlation
with block strength is discussed.
3.10) Fouad M. Khalaf and Alan S. DeVenny, Performance Of Brick
Aggregate Concrete At High Temperatures, Journal of Materials in
Civil Engineering, 2004, Vol. 16, No. 6, December 1, pp556565
This paper presents the results of an experimental investigation
into the effects of high temperatures on the properties of concrete
made with crushed clay bricks as the coarse aggregate. Two types of
brick of different strength were crushed to coarse aggregate that
was used to produce concretes of different strength. Natural
granite aggregate was also used to produce concretes in order to
compare results. The paper presents the results for brick unit
uniaxial compressive strength, aggregate impact value, aggregate
relative density, brick and aggregate water absorption, aggregate
porosity, concrete density, and concrete strength before and after
exposure to high temperatures. The results showed that concrete
could be produced using crushed clay bricks as the coarse aggregate
and at high temperatures clay brick concrete preformed similar or
even better than granite concrete.
3.11) Michele Dondi, Francesca Mazzanti, Paolo Principi,
Mariarosa Raimondo and Giorgio Zanarini, Thermal Conductivity Of
Clay Bricks, Journal of Materials in Civil Engineering, 2004, Vol.
16, No. 1, February 1, pp814
In the present work the thermal conductivity of 29 samples of
clay bricks was measured and the correlations of the thermal
performance with the compositional, physical, and micro structural
features of products were investigated. The results obtained
directed our attention toward a better understanding of the role
played by some parameters ~i.e., mineralogical components and pore
size distribution!, other than bulk density, in improving or
depressing the insulating properties of bricks. Among them, the
unfavorable role of quartz, Ca-rich silicates, and amorphous phase
came out, while the role of pore size and specific surface should
be more accurately evaluated in the structural design of
materials.
3.12) Fouad M. Khalaf and Alan S. DeVenny, Properties Of New And
Recycled Clay Brick Aggregates For Use In Concrete, Journal of
Materials in Civil Engineering, 2005, Vol. 17, No. 4, August 1.
pp456-464
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The testing described in this paper was performed to establish
the physical and mechanical properties of new and recycled crushed
clay brick aggregates for use in portland cement concrete ~PCC!.
Various physical and mechanical properties of eight different types
of aggregates were determined and compared with the limits set out
in the British Standards for aggregate from natural sources used in
concrete. The results were also compared with granite aggregate
that has been proved to be a good natural aggregate for producing
PCC. The results showed that most of the crushed clay-brick
aggregates tested can be used in producing PCC for low-level civil
engineering applications and that some kinds of brick aggregate
possess good physical and mechanical properties that qualify them
for producing high-quality concrete.
3.13) Vijayalakshmi, M.M and Shanmugasundaram, V., Innovative
Building Materials and Methods for Better Thermal Performance of
Residential Buildings, In: Proc, Proceedings of National Conference
on Innovative Technologies in Civil Engineering March 20 & 21,
Department of Civil Engineering, (Edi) K.Subramanian, V.G.Srisanthi
and M.P.Muthuraj, Coimbatore Institute of Technology, Coimbatore,
India, 2006, pp.309-318.
Energy is an important necessity for the growth of a society.
Energy required per capita continuously increases and it results in
serious implications on pollution, climate change and resource
depletion. Making houses energy efficient leads to a reduction in
the amount of energy used. Efficient use of energy will pave way
for sustainable development, as it results in better utilization of
energy and less pollution.
3.14) Amuthakkannan, R., Yogendran, B and Vijayalakshmi, K.,
Measurement of Various Building Parameters using Virtual
Instrumentation and Image Processing Technique, In: Proc,
Proceedings of National Conference on Innovative Technologies in
Civil Engineering March 20 & 21, Department of Civil
Engineering, (Edi) K.Subramanian, V.G.Srisanthi and M.P.Muthuraj,
Coimbatore Institute of Technology, Coimbatore, India, 2006,
pp.473-480.
Nowadays virtual Instrumentation systems (Software based
Instrumentation) are used in various fields, such as Business Core
Transactions, Modern Cars, Automated Teller Machine (ATM), Air
craft Control Systems, Nuclear Power Plants, Manufacturing
Industries etc. In the modern buildings, It is very essential to
predict the various parameters such as temperature, humidity,
vibration, length, breadth and height accurately to control the
various problems like acoustics, overload, over heat etc., The
virtual Instrumentation technique is a software based measurement
and control system using the software Lab View.
3.15) Chakraverty, S., Saini, H and Panigrahi, S.K., Predicting
Product Parameters of Fly Ash-Cement- Sand-Bricks, Construction
Materials, 2007, Vol.160, No.CM2, pp.65-74.
This paper discuss models with ternary systems of fly ash,
cement and sand by using simplex lattice and simplex centroid
design for building bricks. A statistical design with upper and
lower bounds of three component mixtures was adopted to select the
mixture proportions of experimental points required for prediction
of the product parameters, namely compressive strength, bulk
density and water absorption of cement fly ash bricks. The
experimental points include the process parameters such as
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percentage of fly ash, cement and sand and the corresponding
product parameters at different curing periods. Regression models
of various orders for the above design methods are developed.
3.16) A. Arulrajah, J. Piratheepan, T. Aatheesan and M. W. Bo,
Geotechnical Properties Of Recycled Crushed Brick In Pavement
Applications, Journal of Materials in Civil Engineering, 2011,
print April 7, doi:10.1061 (ASCE-In Press)
This paper presents the findings of a laboratory investigation
on the characterization of recycled crushed brick and an assessment
of its performance as a pavement sub base material. The properties
of the recycled crushed brick were compared with the local state
road authority specifications in Australia to assess its
performance as a pavement sub-base material. The experimental
programme was extensive and included tests such as particle size
distribution, modified Proctor compaction, particle density, water
absorption, California Bearing Ratio, Los Angeles abrasion loss,
pH, organic content, static triaxial and repeated load triaxial
tests. California Bearing Ratio values were found to satisfy the
local state road authority requirements for a lower sub-base
material. The Los Angeles Abrasion Loss value obtained was just
above the maximum limits specified for pavement sub-base materials.
The repeat load triaxial testing established that crushed brick
would perform satisfactorily at a 65% moisture ratio level. At
higher moisture ratio levels shear strength of the crushed brick
was found to be reduced beyond the acceptable limits. The results
of the repeat load triaxial testing indicate that only recycled
crushed brick with a moisture ratio of around 65% is a viable
material for usage in pavement subbase applications. The
geotechnical testing results indicates that crushed brick may have
to be blended with other durable recycled aggregates to improve its
durability and to enhance its performance in pavement sub-base
applications.
4.0 TESTING
4.1) Alani, A.F., El-Katib, M.T., Ovanessian, R.A and Korkees,
I.N., Cavity Load Bearing Brick Wall with Steel and Brick Ties,
Journal of Structural Engineering., 1990, Vol.16, No.4,
pp.101-108.
This research paper reports the results of vertical load test on
nine full scale double leaf brick cavity walls. Masonry mortar
1:1:6 (cement: lime: sand) was used as a binding material in the
construction of wall. Two types of ties, brick and standard steel
ties were used to connect the leaves across a 50 mm cavity. One
cavity wall specimen without ties was studied in the test program.
The walls were subjected to vertical loading, both concentric and
eccentric; to investigate their behaviour and ultimate load
carrying capacities, with eccentricity to thickness ratios (e/t)
from 0.00 to 0.30. Test results show that walls with brick
connectors had slight overall improvement in structural behaviour
in terms of ultimate and capacities, moment curvature
relationships, lateral deflections, and tie slippage, when compared
to walls built with British standard steel connectors. Comparison
between theoretical and experimental results are also given
4.2) R. Wang, A. E. Elwi, M. A. Hatzinikolas and J. Warwaruk,
Tests Of Tall Cavity Walls Subjected To Eccentric Loading, Journal
of Structural Engineering, 1997, Vol. 123, No.7, pp0912-0919
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This paper presents a test program on full-scale reinforced
slender shear connected cavity walls subjected to an eccentric
compressive loading. A total of nine walls were tested. All
specimens were constructed with a partially grouted andreinforced,
190-mm concrete masonry block wythe and a 90-mm burnt clay brick
wythe. All had a slenderness ratio of height to backup wythe
thickness of 27.8 and, except for one specimen, all walls had a
75-mm wide cavity. The primary variable, was the axial force
eccentricity. The eccentricity varied both in magnitude from tl2 to
t/3, and in direction, either towards or away from the brick wythe.
Some walls were tested with a single curvature, others were tested
in double curvature. The load-displacement response, failure mode,
and ultimate load capacities are examined and reported along with
the observation and discussion.
4.3) Qamaruddin, M and Mauroof, A.L.M., A New Model for Lateral
Stiffness of Shear Walls with Openings, Journal of Structural
Engineering, 1998, Vol.25, No.2, pp.103-107.
In masonry structures, the walls are designed to carry both the
vertical and lateral loads. The magnitude of lateral load carried
by each wall depends on its relative stiffness compared to overall
stiffness of the structure. Although, various methods are known for
the computation of the lateral stiffness of shear walls subjected
to lateral loads resulting from wind and earthquakes, the presence
of openings with appreciable percentage of total area of the wall,
greatly affects the stiffness of the wall. Existing methods assume
fixity at the pier-spandrel junction of the wall piers to estimate
their stiffness. A new method is proposed in this paper which
considers the flexibility of the diaphragm/spandrel at the
top/bottom of the piers in estimating the lateral stiffness of the
wall. Results obtained by the proposed method and the finite
element method indicate excellent agreement.
4.4) Manamohan Kalgal, R and Prakash, M.R., Effect of Joint
Thickness on Compressive Strength of Stack Bonded Prisms-A
Preliminary Investigation, Tech. Report, Dept of Civil Engineering
Department, M.S.Ramaiah Institute of Technology, Bangalore, India,
1998, pp.96-101.
Strength and thickness of mortar bed joint play vital role in
strength and behavior of the masonry. The paper outlines an
experimental study undertaken to investigate the effect of joint
thickness on the strength of masonry prisms. The factors considered
are (a) types of mortar- cement mortar and soil-cement mortar, (b)
thickness of mortar bed joint and (c) type of masonry unit bricks
and soil cement blocks. The investigation is aimed at studying the
variation in the strength and mode of failure.
4.5) Matey, M.B., Strength and Behaviour of Concrete Hallow
Block Masonry Walls in Compression, Tech. Report, Civil Engineering
dept, Visveshvaraya Regional College of Engineering, Nagpur, India,
1998, pp.102-106.
This paper includes the characteristics of material used for
investigation, method of producing structurally efficient hollow
blocks, construction of wall panels, detailed test procedure and
the test results. The main aim of the investigations is to study
slenderness ratio parameter for hollow block wall panels under
uniformly distributed compressive load. Total ten panels of
different height are tested . The end condition of
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14
all the wall panels is same. The relation between stress
reduction factor and slenderness ratio is compared with the values
in I.S. and experimental results. The other parameters studied are
ratio of wall strength to block strength, ratio of experimental
ultimate load to theoretical permissible load on wall,
stress-strain relationship, strain distribution at the blocks and
along the height of the walls and cracking and failure pattern of
wall panels. Behavior of walls was also observed during application
of gradually increasing uniformly distributed load. It was observed
that the wall panels failed by vertical cracking followed by
cracking of mortars joints, blocks and stripping of face panels of
blocks. It was observed that the strain along perpend mortar joints
was more than that of bedding mortar joints. The average ratio of
wall strength to block strength was found to be 0.71. The ratio of
experimental ultimate load to theoretical permissible load on walls
was found to be 7.32. The stress reduction factor given in I.S.
Code was found to be higher than experimental results for
corresponding slenderness ratio.
4.6) Sarangabani, G and Sajid, S.A., Compressive Strength and
Geological Characteristics of Natural Building Stones, Tech.
Report, Dept of Civil Engineering, NIT., Mysore, India, 1998,
pp.107-109.
This paper deals with the determination of compressive strength
and geological characteristics of natural building stones. Stones
from twelve different locations have been considered in this
experimental investigation. An attempt has also been made to
correlate the geological characteristics to the compressive
strength of the stones.
4.7) Walker, P., Strength and Durability Testing of Earth
Blocks, Tech. Report, Dept of Architecture and Civil Engineering,
University of Bath, UK, 1998, pp.110-118.
The paper describes methods currently used for compressive and
bending strength testing of earth blocks. An experimental program
undertaken to consider the influence of both test procedure and
specimen geometry on unit compressive strength is outlined.
Un-stabilized and cement stabilized compressed earth blocks have
been fabricated using different blended soils and compacted using a
constant volume manual press. The effects of specimen geometry on
experimental compressive strength are described and aspect ratio
correction factors for unconfined unit strength are outlined.
Proposals for a unified approach to compressive strength testing
are also suggested. Bending strength testing is commonly used as an
indirect method of strength assessment, as it is more radialy
suited to in-situ quality control testing than compression testing.
The experimental correlation between compressive and bending
strength is presented and general guidelines for flexural testing
are also proposed. Finally, the correlation of strength with other
important characteristics, such as erosion resistance, is
presented.
4.8) Santos, F.A., Sinha, B.P and Roman, H.R., Lateral Behaviour
of Masonry Shear Wall with Filled and Unfilled Vertical Mortar
Joints, Tech. Report, Dept of Civil Engineering, University of
Edinburgh & Santa Catarina, UK & Brazil, 1999,
pp.164-170.
This paper describes an investigation carried out to study the
behaviour of masonry shear wall structures under lateral loading. A
series of experiments were carried out
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15
on 1/3-scale masonry structures with filled and unfilled
vertical mortar joints. Deflection and strains were measured during
the experiment. Finite Element analysis was carried out, which
gives very good agreement with experimental results provided the
orthotropic properties of masonry is taken into account.
Considering masonry as isotropic will underestimate the top
deflection and the stresses along the wall at the bottom. From the
experiments it seems that the strain along the length of shear wall
is non-linear even at very low level of the shear load.
4.9) Sivarama Sarma, B., Sreenath, H.G., Bhagavan, H.G.,
Vimalanandam, V., Experimental Studies on Un-reinforced and
Reinforced Masonry Panels under In-plane Monotonic Lateral Loads,
Tech. Report, Structural Engineering Research Center., Chennai.,
India, 1999, pp 187-192.
The code of practice for earthquake resistant design of
buildings, IS: 1893, is being revised with the concepts of
ductility based design. Shear wall are the main structural elements
that resist the in plane lateral loads developed due to seismic
action. The strength and ductility characteristics of shear walls
vary predominantly with the amount of horizontal and vertical
reinforcement, type of masonry panel, strength of block or brick
and mortar, fixed at base etc. This paper lists the summary of
various tests carried out on hollow concrete blocks, bricks, prisms
and wall panels incorporating conventional bricks and structural
grade hollow concrete blocks under in plane monotonic lateral load,
along with super imposed gravity loads. Force reduction factors
useful for seismic strength design are also derived. The
experimental results indicate that the reinforcement in masonry
shear wall improves the ductility, and shear load characteristics.
The shear stress results are also compared with permissible values
as given in BS: 5628-1995, ACI: 530-95 and IS: 1905-1987
4.10) Aishebani, M.M and Shina, S.N., Stress-Strain
Characteristics of Brick Masonry under Uni-axial Cyclic Loading,
Journal of Structural Engineering, 1999, Vol.125, No.6,
pp.600-604.
A series of laboratory tests were carried out on half-scale and
plast brick work panels subjected to uni-axial cycle loading: (1).
Normal to the bed joint; (2). Parallel to the bed joint. Failure
due to cyclic compressions was usually characterized by a
simultaneous failure of brick units and head joints or by splitting
in the bed joints depending on the weather the panel was loaded
normal or parallel to the bed joint, respectively. The
characteristics of the stress-strain relationship of the two
loading conditions are presented in this paper. Envelope, common
point, and stability point stress strain curves were established
based on test data, and an exponential formula was found to provide
a reasonable fit to the test data. It was concluded that the peak
stress of the stability point curve can be regarded as the maximum
permissible stress level that is found to be approximately equal to
two thirds of the failure stress. It was also observed that the
permissible stress level depends on the plastic strain level
present in the material due to cyclic loading.
4.11) Choubey, U.B., Gupta, U and Maidasani, A., An Experimental
Study of Flexural Tensile Strength Calcium Silicate Brick Masonry,
Journal of Structural Engineering, 1999, Vol.26, No.2,
pp.143-148.
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16
Brick panels used essentially as claddings for buildings, have
to withstand lateral wind pressure besides other loads. The results
of the experiments show that the tensile bond strength is affected
by the moisture content of brick. It almost reduces to zero if the
bricks are saturated at the time of laying. On the contrary, if
brick is dry and has high suction rate, there will be a partially
hydrated zone in the cement paste up to a depth of several
millimeters. Experiments on the interaction between brick and
cement paste have shown that the mechanical bond between these
components is considerably affected by their specific surfaces and
capillary dimensions. In a physical- chemical process a micro layer
of ettringite is formed at the interface and tensile bond strength
is critically affected by the respective mean diameter of the pores
of the brick and of the micro crystals of the ettringite. It is
necessary that the pore size of the brick material to be greater
than 0.05 mm for a mechanical bond to be formed and also for the
cement to be properly hydrated behind the ettringite layer.
4.12) Alessandra Aprile, Andrea Benedetti and Fabio Grassucci,
Assessment Of Cracking And Collapse For Old Brick Masonry Columns,
Journal of Structural Engineering, 2001, Vol. 127, No. 12,
December, pp14271435
This paper presents experimental and theoretical research
focused on the structural behavior of old brick masonry columns. To
gather data on the role played by the evolution of brick-mortar
interaction stresses when the load is increasing up to failure, six
prototype columns made with 17th century bricks and lime mortar
were prepared and tested. The instrumentation layout allowed the
writers to carefully detect the cracking load and to pick out some
selected strain values. Afterward, the obtained data were discussed
on the basis of the well-known hypotheses characterizing the
masonry stress fields and collapse events. A simple modification of
the classical Hilsdorf equilibrium equation motivated by the
observed experimental behavior led to a sensible interpretation of
the nested phases of brittle failure endured by the masonry up to
the collapse. In order to account for the changing interaction
stress between mortar layers and brick courses, an influence factor
was defined to restore the internal equilibrium during the
evolution of the column damage states. In fact, the introduced
mortar influence factor holds an important position in the
definition of the margin between the cracking and global failure
phases, explaining why the collapse load of the column is higher
than the first cracking load. Moreover, thanks to some
simplifications in the analyses, it was shown that this key
parameter plays the role of a strength amplification factor linked
to the damage evolution, and that consequently it can be used in
the approximate evaluation of the remaining reliability of the
masonry column after the stabilized cracking phase.
4.13) Hall, J.D., Schuman, P.M and Hamilton, H.R-III., Ductile
Anchorage for Connecting FRP Strengthened of Under Reinforced
Masonry Building, Journal of composites for construction., 2002,
Vol.6, No.1, pp.3-10.
Fiber reinforced polymer (FRP) composites have been examined as
a convenient and cost effective means of strengthening
un-reinforced structures. Seismic design in the United States is
almost entirely based on the assumption that the structural systems
provides a ductile failure mode. FRP strengthened masonry walls
inherently have brittle failure modes due to the nature of the
strengthening system. The concept explored in this article is the
introduction of ductility using a hybrid strengthening system. This
involves the placement of structural steel or reinforcing steel at
critical
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17
locations in the lateral force resisting system. This article
presents the testing and analysis of a ductile structural steel
connection that can be used to strengthen the connection of FRP
strengthened shear walls to the foundation. The connection also
increases energy dissipation. Results indicate that a ductile
failure mode can be attained when the connection is designed to
yield prior to the failure of the FRP strengthening.
4.14) Asteris, P.G., Lateral Stiffness of Brick Masonry
In-Filled Plane Frames, Discussions and closures, Journal of
Structural Engineering, 2003, Vol.129, No.8, pp.1071-1079.
The author investigates the lateral stiffness of in-filled
frames, particularly focusing on the reduction of stiffness due to
opening. The finite element method is used to analyze various
configuration. Infill behaviour in itself is quite complex and
openings add to the complexity of the problem. Thus the author is
to be commended for examining problem .
4.15) Michael Craig Griffith, nelson t. k. lam, john leonard
wilson and kevin doherty, Experimental Investigation Of
Unreinforced Brick Masonry Walls In Flexure, journal of structural
engineering, 2004, vol. 130, no. 3, march 1, pp423432
This paper presents the results of static and dynamic tests on
unreinforced brick masonry wall panels subject to out-of-plane
loading. Fourteen wall panels were tested. The test program
included static, free-vibration, and dynamic tests using harmonic
support, impulse support, and earthquake support motion. The
experimental results indicate that displacement, rather than
inertia force amplitude, determines whether an unreinforced masonry
wall will collapse during inertial ~seismic! loading. An empirical
forcedisplacement relationship is proposed that can be used for a
substitute structure in a displacement-based method of
analysis.
4.16) Ghobarah, A and Galal, K.E.M., Out-of-Plane Strengthening
of Un-reinforced Masonry Walls with Openings, Journal of Structural
Engineering, 2004, Vol.8, No.4, pp.298-305.
Collapse of un-reinforced masonry (URM) walls is the cause of
many casualties during extreme loading events. The objective of
this current research was to investigate effective and practical
approaches for strengthening URM block walls with openings to
resist extreme out-of-plane loads. Five full-scale masonry block
walls were constructed. The walls had different opening
configurations such as a single center window, one window off
center, two windows, a wide window and a door. The walls were
tested when subjected to uniformly distributed lateral load up to
failure. The walls were then strengthened using carbon
fiber-reinforced polymer laminate strips and then re-tested. The
walls were set up in a vertical test frame and were subjected to
cyclic out-of-plane distributed pressure using an airbag. Failure
of the un-strengthened URM block wall was along the mortar joints.
In the strengthened walls, failure occurred in the mortar joints as
well as in concrete blocks near the carbon strips. The lateral load
carrying capacity of the strengthened walls was found to be
significantly higher than that of the un-strengthened walls and had
much more ductile performance.
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4.17) Griffith, M.C., Lam, N.T.K., Wilson, J.L and Doherty, K.,
Experimental Investigation of Un-reinforced Brick Masonry Walls in
Flexure, Journal of Structural Engineering, 2004, Vol.130, No.3,
pp.423-432.
This paper presents the results of static and dynamic tests on
un-reinforced brick masonry wall panels subject to out-of-plane
loading. Fourteen wall panels were tested. The test program
included static, free-vibration, and dynamic tests using harmonic
support, impulse support, and earthquake support motion. The
experimental results indicate that displacement, rather than
inertia force amplitude, determines whether an un-reinforced
masonry wall will collapse during inertial (seismic) loading. An
empirical force displacement relationship is proposed that can be
used for a substitute structure in a displacement based method of
analysis.
4.18) Tan, K.H and Patoary, M.K.H., Strengthening of Masonry
Walls against Out-of-Plane Loads using Fiber-Reinforced Polymer
Reinforcement, Journal of Structural Engineering, 2004, Vol.8,
No.1, pp.79-87.
Thirty masonry walls strengthened using three different
fiber-reinforced polymer (FRP) systems, with three anchorage
methods, were fabricated and tested under a concentrated load over
a 100 mm square area or a patch load over a 500 mm square area. The
test results indicated a significant increase in the out-of-plane
wall strength over the un-strengthened wall. While failure occurred
in the un-strengthened wall by bending, four different mode
failure, that is punching shear through the bricks, de-bonding of
FRP reinforcement from the masonry substrate, crushing of bricks in
compression, and tensile rupture of FRP reinforcement, were
observed in the strengthened walls, depending on the types and
configuration of FRP and anchorage systems. With appropriate
surface preparation and anchorage systems, premature failure due to
FRP de-bonding is prevented. Based on the principles of strain
compatibility and force equilibrium, simple analytical models are
presented to predict the ultimate load carrying capacity of the
strength.
4.19) Paquette,J., Bruneau, M and Brzev, S., Seismic Testing of
Repaired Un-Reinforced Masonry Building having Flexible Diaphragm,
Journal of Structural Engineering, 2004, Vol.130, No.10,
pp.1487-1496.
The In-plane rocking behaviour of un-reinforced masonry walls is
generally perceived as a stable desirable behaviour. However, there
may be instances where the available lateral resistance of such
walls would be in-adequate. In that perspective, fiberglass strips
were applied to damaged un-reinforced masonry (URM) shear wall to
increase theie inplane lateral load resisting capacity. This paper
reports on the dynamic response and behaviour of the full scale one
story un-reinforced brick masonry building specimen having a
flexible wood floor disphragm.
4.20) Moerman, W., Taerwe, L., Waele, W.D., Degrieck, J and
Himpe, J., Measuring Ground Anchor Forces of a Quay Wall with Bragg
Sensors, Journal of Structural Engineering, 2005, Vol.131, No.2,
pp.322-328.
The use of optical fiber sensors for monitoring civil
engineering structures is increasing continuously. One of the most
frequently applied sensor types is the so called Bragg sensors,
which is primarily used to measure structural deformations. Due
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19
to some inherent advantages these sensors are ideally suited for
long term monitoring purposes. This paper describes the development
of the load cell, based on Bragg sensors, to measure the forces in
the ground anchors of the quay wall. The test results compared well
with the analytical predictions.
4.21) Mullins, G., Sen,R., Suh, K and Winters, D., Underwater
Fiber Reinforced Polymers Repair of Pre-stressed Piles in the Allen
Creek Bridge, Journal of Composites for Construction, 2005, Vol.9,
No.2, pp.136-146.
This paper presents an overview of a demonstration project in
which corroding pre-stressed piles located in tidal waters were
wrapped underwater using carbon and glass fiber reinforced polymer
material. An innovative instrumentation scheme was developed to
allow assessment of the pre-wrap and post-wrap corrosion state
using linear polarization. This system is simple to install and
eliminate the need for wiring and junction boxes, the underwater
wrap used to unique water activated urethane resin system that
eliminated the need for cofferdam construction. Linear polarization
measurements taken before and after wrapping indicate that the
corrosion rate in the wrapped specimens is consistently lower than
those in its un-wrapped counterpart. These preliminary findings are
encouraging and suggest that underwater wrapping without cofferdam
construction may provide a cost effective solution for pile
repair.
4.22) Antoniades, K.K, Salonikios, T.N and Kappos, A.J., Tests
on Seismically Damaged Reinforced Concrete Walls Repaired and
Strengthened using Fiber-Reinforced Polymer, Journal of Composites
for Construction, 2005, Vol.9, No.3, pp.236-246.
The behaviour of six 1:2.5 scale reinforced concrete cantilever
wall specimens having an aspect ratio 1.5, tested to failure and
subsequently repaired and strengthened using
fiber-reinforced-polymer (FRP) sheets is investigated. Specimens
were first repaired by removing heavily cracked concrete., lap
splicing the fractured steel bars by welding new short bars,
placing new hoops and horizontal web reinforcement and finally
casting non shrink high strength repair mortar. The specimens were
then strengthened using FRP sheets and strips, with a view to
increasing flexural as well as shear strength and ductility.
4.23) Hamid, A.A., El-Dakhakhni, W.W., Hakam, Z.H.R and Elgaaly,
M., Behaviour of Composites Un-reinforced Masonry Fiber-Reinforced
Polymer Wall Assemblages under In-Plane Loading, Journal of
Composites for Construction, 2005, Vol.9, No.1, pp.73-83.
An experimental investigation was conducted to study the
in-plane behaviour of face shell mortar bedded un-reinforced
masonry (URM) wall assemblages retrofitted with fiber reinforced
polymer (FRP) laminates. Forty two URM assemblages were tested
under different stress conditions present in masonry shear and
infill walls. Tests included prisms loaded in compression with
different bed joints orientation, diagonal tension specimens, and
specimens loaded under joint shear.
4.24) Dakhakhni, W.W.E., Drysdale, R.G and Khattab, M.M.,
Multilaminate Macromodel for Concrete Masonry: Formulation and
Verification, Journal of Structural Engineering, 2005, Vol.132,
No.12, pp.1984-1996.
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20
A macromodel was developed to predict the in-plane behaviour of
concrete masonry. In this multilaminate model, the masonry
assemblage is replaced by an equivalent material which consists of
a homogenous medium intersected by two sets of planes of weakness
along the head and bed joints.
4.25) Fouad M. Khalaf, New Test For Determination Of Masonry
Tensile Bond Strength, Journal of Materials in Civil Engineering,
2005, Vol. 17, No. 6, December 1, pp725732
The bond strength between masonry units and mortar has been of
considerable interest to researchers for some time. The flexural
bond strength of masonry in particular is needed for the design of
masonry walls subjected to horizontal forces applied normal to the
face of the wall, such as wind forces. Researchers and standards
have suggested different kinds of specimens and test procedures to
determine the flexural bond strength. These include the test on
wallettes (small walls), the bond wrench test, the Brench test, the
direct tensile test, and the crossed couplet test. Each of these
tests has its own drawbacks and problems. This paper presents a
test method to determine the flexural bond strength, f fb, by
bending. The test could be used for laboratory research to
investigate the many factors affecting bond strength and also for
deriving design values for masonry standards. The specimen is
constructed from two brick units in a Z-shaped configuration, and
three-point loading induces a flexural bond failure parallel to the
bed joint. Three different types of clay brick, one calcium
silicate brick, and three different types of mortar were used in
the experimental program. The results derived show that the
proposed new specimen and test procedure are capable of determining
the flexural bond strength easily and accurately.
4.26) Carolin, A and Taljsten, B., Experimental Study of
Strengthening for Increased shear Bearing Capacity, Journal of
Composites for Construction, 2005, Vol.9, No.6, pp.488-496.
The need for structural rehabilitation of concrete structures
all over the world is well known and a great amount of research is
going on in this field. The use of carbon fiber reinforced polymer
(CFRT) plate bonding has been shown to be a competitive method with
regard to both structural performance and economic factors. This
method consists of bonding a thin carbon fiber laminate or sheet to
the surface of the structure to act as an outer reinforcement
layer. However most research in this area has been undertaken to
study flexural behaviour. This paper deals with shear strengthening
of reinforced concrete members by use of CFRT. Test on rectangular
beams 3.5 to 4.5 m long have been undertaken to study different
parameters, such as fatigue, anchorage, and others. This strain
field in shear spans of beams simultaneously subjected to shear and
bending is also studied. The tests presented also contribute to the
existing literature on tests of concrete members strengthened for
increased shear capacity.
4.27) Prota, A, Marcari, G., Fabbrocino, G and Aldea, C.,
Experimental In-Plane Behaviour of Tuff Masonry Strengthened with
Cementitious Matrix-Grid Composites, Journal of Composites for
Construction, 2006, Vol.10, No.3, pp.223-233.
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21
Tuff building are a significant part of the Mediterranean area
and are to be presented from a structural view point especially in
seismic areas. Over the past few decades, the interest in
strengthening of historical tuff masonry structures has led to
developing specific and non-invasive architectural and engineering
strategies. In the present paper, a comprehensive experimental
program on tuff masonry panel is presented; the results are
intended as a contribution to the knowledge of in-plane behaviour
of tuff masonry strengthened with composite materials.
4.28) Almusallam, T.H and Al-Salloum, A., Behaviour of FRP
Strengthened In-fill Walls under In-plane Seismic Loading, Journal
of Composites for Construction, 2007, Vol.11, No.3, pp.308-318.
The present paper investigates the suitability and effectiveness
of fiber-reinforced polymer (FRP) in strengthening and or repairing
un-reinforced masonry infill walls in reinforced concrete frames
which are subjected to in-plane seismic or cyclic loading. For this
purpose, a detailed experimental program was conducted. Specimens
geometry, test setup, instrumentation, and a loading procedure that
simulates earthquake loadings are presented in a detailed
fashion.
4.29) Wight, G.D., Kowalsky and Ingham, J.M., Shake Table
Testing of Post-Tensioned Concrete Masonry Walls with Openings,
Journal of Structural Engineering, 2007, Vol.133, No.11,
pp.1551-1559.
The in-plane seismic response of post tensioned concrete masonry
walls with openings is investigated by means of shake table
testing. A test program was initiated to verify the seismic
performance of a wall system for use in residential construction.
Two single story in-plane wall tests were conducted initially to
study the effect of door and window openings and wall corners.
4.30) Flint, G., Usmani, A., Lamont, S., Lane, B and Torero, J.,
Structural Response of Tall Buildings to Multiple Floor Fires,
Journal of Structural Engineering, 2007, Vol.133, No.12,
pp.1719-1732.
This paper reports on investigation of the effects of fire on
long span truss floor systems in a tall building environment. The
effect of the fire spread over multiple floors of a building are
the focus of this research., especially where this may lead to
progressive collapse. The results from an investigation of a two
dimensional model of a multistory office building analysis are
presented.
4.31) Moon, F.L., Yi, T., Leon, R.T and Kahn, L.F., Testing of a
Full-Scale Un-reinforced Masonry Building Following Seismic
Strengthening, Journal of Structural Engineering, 2007, Vol.133,
No.9, pp.1215-1226.
To investigate the effectiveness of several seismic
strengthening techniques, a full scale un-reinforced masonry (URM)
structure was subjected to slowly applied lateral load reversals
after the application of fiber reinforced plastic overlays, near
surface mounted rods, and vertical post tensioning.
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22
4.31) Popehn, J.R.B., Schultz, A.E and Drake, C.R., Behaviour of
Slender, Post-tensioned Masonry Walls under Transverse Loading,
Journal of Structural Engineering, 2007, Vol.133, No.11,
pp.1541-1550.
A conceptual model of the response of slender, post tensioned
masonry walls to uniformly distributed, transverse loading is
introduced and vertical through an experimental program. To
validate the model, 12 simply supported 3.54 m (11.6 ft) tall walls
with 810x100 mm cross-section were tested under monolithically
increasing transverse loads. Six walls were built using cored clay
brick and the remaining six using hallow concrete block. The walls
were post tensioned using threaded steel bars with six walls
featuring unrestrained tendons, while the other six had restrained
and three magnitudes of effective pre-stress were investigated.
Initial responses to transverse load was linear, but cracking was
observed over a broad range of loading. The response of the wall
specimens is traced through crack propagation, hinge formation, and
development of the plastic section.
4.32) M. Harajli, H. ElKhatib and J. Tomas San-Jose, Static and
cyclic out-of-plane response of masonry walls Strengthened using
textile-mortar system, Journal of Materials in Civil Engineering,
2010, Vol. 22, No. 11, November1, pp1171-1180
The work presented in this paper is a part of a comprehensive
research project aimed at developing and testing a system for
strengthening historical buildings. The system is composed of a
combination of textile mesh and mortar. Representative wall
specimens were tested for their out-of-plane flexural behavior
under static and cyclic loadings. The parameters investigated
include the types of masonry wall (concrete block, sandstone, and
brick), mortar (natural lime and cement-based), and textile
(bitumen coated E-glass, basalt, or coated basalt fibers).
Companion specimens, strengthened using a steel wire mesh, were
also tested for comparison. All textile-mortar reinforced masonry
(TRM) wall specimens failed in a combination of transverse
detachment of the textile-mortar matrix due to the transverse
displacement of the blocks relative to each other, and combined
transverse shear-tension fracturing of the textile fibers.
Regardless of the mode of failure, the TRM specimens developed a
substantial increase in their out-of-plane load and displacement
capacities under static loading, and low stiffness and strength
degradation, and considerable displacement capacities under cyclic
loading. The wire mesh-mortar reinforced masonry specimens
developed the highest load capacity but were the least ductile when
compared to the TRM specimens.
4.33) Francesca da Porto, Giovanni Guidi, Enrico Garbin and
Claudio Modena, In-plane behavior of clay masonry walls:
experimental Testing and finite-element modeling, Journal of
Structural Engineering, 2010, Vol. 136, No. 11, November1,
.pp13791392
Extensive experimental research aimed at defining the in-plane
cyclic behavior of three types of load-bearing masonry walls,
assembled with perforated clay units, and various types of head and
bed joints was carried out. Experimental behavior was modeled with
four types of nonlinear finite-element models. Both macromodeling
and micromodeling strategies, implementing either isotropic or
orthotropic material laws, were adopted. Two simplified criteria
were proposed for calibrating the models, one for defining
orthotropic properties starting from perforated unit geometry and
the
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23
other for defining expanded unit and interface element
properties in micromodels. The procedures adopted for model
calibration established the reliability of various modeling
strategies. Results allow some conclusions to be drawn about the
reliability of diagonal compression tests for large unit masonry,
the stress distribution and different behaviors of masonry made
with different head and bed joints, and the influence of unit
strength on the in-plane behavior of masonry.
4.34) Marco Di Ludovico, Claudio DAmbra, Andrea Prota and
Gaetano Manfredi, FRP Confinement Of Tuff And Clay Brick
Columns:Experimental Study And Assessment Of Analytical Models,
Journal of Composites for Construction, 2010, Vol. 14, No. 5,
October 1, pp583596
In recent years, fiber-reinforced polymer (FRP) wrapping
effectiveness has been clearly confirmed especially with reference
to concrete structures. Despite evident advantages of FRP based
confinement on members subjected to compressive overloads due to
static or seismic actions, the use of such technique in the field
of masonry has not been fully explored. Thus, to assess the
potential of confinement of masonry columns, the present paper
shows the results of an experimental program dealing with 18 square
cross sections (listed faced tuff or clay brick) masonry scaled
columns subjected to uniaxial compression load. In particular,
three different confinement solutions have been experimentally
analyzed in order to evaluate and compare the effectiveness of
uniaxial glass FRP, carbon FRP, and basalt FRP laminates wrapping.
The main experimental outcomes are presented and discussed in the
paper considering mechanical behavior of specimens, axial
stress-axial strain relationships, and effective strains at failure
on the reinforcement. Test results have showed that the
investigated confining systems are able to provide significant
gains both in terms of compressive strength and ductility of
masonry columns. Results of the presented experimental activity
along with data available in the literature have been finally used
to assess the reliability of the main existing analytical models;
refined equations have been then proposed to minimize the
scattering between theoretical predictions and experimental
available data.
4.35) Daniel V. Oliveira, Ismael Basilio and Paulo B. Loureno,
Experimental Behavior Of Frp Strengthened Masonry Arches, Journal
of Composites for Construction, 2010, Vol. 14, No. 3, June1,
pp312322
This paper deals with the experimental behavior of solid clay
brick masonry arches strengthened with glass fiber-reinforced
polymer composites. Twelve half-scaled segmental masonry arches
subjected to a load applied at the quarter span were tested under
displacement control up to failure. The arches were built using
handmade low strength bricks and a commercial lime-based mortar,
trying to mimic ancient structures. Besides reference unreinforced
arches, five different strengthening arrangements, including the
use of spike anchors, were studied. The experimental results
provide significant information for validation of advanced
numerical models and analytical tools and for code drafting. The
experimental results also show that (1) only continuous
strengthening strategies are able to prevent typical local failure
mechanisms of unreinforced arches; (2) strengthening at the
intrados is the most effective option to increase strength; and (3)
strengthening applied at the extrados provides the higher
deformation capacity prior to failure, endowing arches with
considerable ductility behavior.
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24
4.36) Vladimir G. Haach, Graa Vasconcelos and Paulo B. Loureno,
Experimental analysis of reinforced concrete block Masonry walls
subjected to in-plane cyclic loading, Journal of Structural
Engineering, 2010, Vol. 136, No. 4, April 1,.pp452462
An innovative system for reinforced concrete masonry walls based
on the combination of vertical and horizontal trussed reinforcement
is proposed. The mechanical characterization of the seismic
behavior of such reinforced masonry walls is based on static cyclic
tests carried out on panels with appropriate geometry. The
influence of the factors influencing the in-plane cyclic behavior
of concrete masonry walls, such as the horizontal reinforcement,
precompression, and masonry bond pattern, is discussed. The results
are analyzed in terms of failure modes and force versus
displacement diagrams, from which the seismic performance is
assessed based on the ductility and energy capacity dissipation.
The results stressed that the increase on the precompression level
leads to a stiffer and more brittle lateral behavior of the masonry
walls. The presence of horizontal reinforcement ensures better
control and better distribution of cracking, even if only a
marginal increase of lateral strength was found in the particular
testing program.
4.37) Khaled Galal and Munir Alp Enginsal, Flexural Behavior Of
Gfrp-Reinforced Concrete Masonry Beams, Journal of Composites for
Construction, 2011, Vol. 15, No. 1, February 1, pp2131
An experimental and analytical study is conducted in order to
investigate the flexural behavior of masonry beams that are
internally reinforced using glass fiber-reinforced polymers _GFRP_
rebars. Seven reinforced masonry beams with 4.0- and 2.4-m spans
were tested under four-point bending setup. The beams were loaded
monotonically up to failure. One had two courses of hollow concrete
masonry units and the remaining six beams had three courses. Two
masonry beams were reinforced using conventional steel rebars and
were considered as the control specimens. The remaining five beams
were internally reinforced using GFRP rods with different
reinforcement ratios. Beams were detailed to have sufficient shear
reinforcement such that they do not fail in shear. Flexural
capacity, deformation, curvature, and strains of the tested
GFRP-reinforced and steel-reinforced masonry beams were compared
and discussed. Using the acquired data from the experimental and
analytical studies, effectiveness of GFRP rods as internal
reinforcement for concrete masonry beams is demonstrated.
4.38) N. Augenti, F. Parisi, A. Prota and G. Manfredi, In-Plane
Lateral Response Of A Full-Scale Masonry Sub Assemblage With And
Without An Inorganic Matrix-Grid Strengthening System, Journal of
Composites for Construction, 2011, Vol. 15, No. 4, August 1,
pp578590
A full-scale unreinforced masonry (URM) wall with an opening was
tested under in-plane lateral loading. The wall was first subjected
to monotonically increasing displacements until a moderate damage
level was reached. The damaged specimen was then cyclically tested
up to almost the same maximum drift attained during the monotonic
test to investigate the effects of previous damage on its nonlinear
response. Finally, the masonry wall was repaired with inorganic
matrix-grid (IMG) composites and subjected to a cyclic displacement
controlled test up to a near-collapse state. Most
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25
of the observed damage developed in the spandrel panel affecting
both lateral resistance and strength degradation. Rocking of piers
governed lateral stiffness and hysteretic response, which was
characterized by low residual displacements and re-centering
behavior. The comparison between the experimental
force-displacement curves demonstrated that the IMG strengthening
system was able to provide energy dissipation capacity to the
spandrel panel, restoring load-bearing capacity of the as-built
wall, and delaying strength degradation that was indeed observed at
larger displacements. Bilinear idealizations of force-displacement
curves allowed the identification of displacement ductility, global
over strength, and strength reduction factor of the tested wall
systems.
5.0 ANALYSIS AND DESIGN
5.1) Vermeltfroot, A.T., Groot, W.P., Wijen, E., Strains in
Re-pointed Masonry Under Compression: Preliminary Investigation
Using ESPI, Tech. Report, Eindhoven University of Technology, The
Netherlands, 1985, pp.138-147.
This paper reports the results of preliminary investigations on
the mechanical behaviour under compressive load of two combinations
of re-pointing and bedding mortars used in combination with two
types of bricks. The mechanical behaviour is studied using ESPI
(Electronic Speckle Pattern Inter-ferometry ). Special attention is
paid to stress concentrations due to the mechanical incompatibility
of the bedding and pointing mortar. In particular, hard re-pointing
material applied on :soft bedding mortar shows a high degree of
mechanical incompatibility.
5.2 Cavaiheiro, O.P., Pozzobon, A.N and Santos, M.D.F., Diagonal
Tensile and Compressive Strength of Hollow Clay and Concrete Block
Specimens, Tech. Report, Federal University of Santa maria, Brazil,
1987, pp.157-163.
The paper presents some experimental results of diagonal tensile
strength of hollow clay and concrete blocks specimens with filled
and unfilled head (vertical) joints as well as results of
compressive strength of blocks and stack bounded prisms of two and
three units for both types of block. Three types of mortar mixes
(low, medium and high) were used in the investigation. It appears
that the diagonal tensile strength is significantly lower for
specimen with unfilled head joints compared to specimen with filled
head joints: and the ratio of compressive strength of the block
unit is considerably higher for concrete block than for clay
block.
5.3) Guha, A.L., An Isotropic Elasto Plastic Model for Masonry
Wall Subjected to Biaxial In-plane Loading, Tech. Report, Bengal
Eng College., Howrah., India., 1987, pp.171-186.
A material model suitable for finite element analysis subjected
to in-plane loading is presented. To account for the directional
strength properties at failure a generalized anisotropic quadratic
failure criterion has been used to model the non-linear behaviour
of masonry. The magnitude of the interaction term is restrained in
such a way that the shape of the failure surface is ellipsoidal.
Sensitivity and analysis has been carried out to select the type of
test results to be used for the determination of the interaction
strength parameter. The failure criterion agrees well with the
experimental failure envelope for uni-axial and biaxial compressive
loading. Smeared crack approach with
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26
fixed crack angle is adopted for modeling of the cracking
behaviour of masonry. Maximum stress criterion for anisotropic
material has been used for initiation and propagation of cracks.
Tensile strain softening is employed for gradual release of tensile
stress after cracking. Closing and reopening of cracks are allowed
in this model following the secant path.The finite element method
of analysis incorporating the proposed material model has been
employed to study the in plane behaviour of the masonry shear walls
to demonstrate the suitability of the material model, structural
idealization and numerical techniques by comparing the computed
behaviour with the experimental results. The predicted behaviour is
in good agreement with the experimental results.
5.4) Neto, J.A.D.N., Correa, M.R.S and Ramalho, M.A Analysis of
Torsion Effects on the Bracing Systems of Masonry Buildings, Tech.
Report, USP-University of Sao Paulo, Brazil, 1990, pp.193-201.
The brazing system of a masonry building is usually designed as
a plane association if isolated walls. Although simple to use this
model fails to allow for the simulation of important aspects of
bracing system behaviour, such as those related to the overall
torsion of the building. The proposed numerical modeling using beam
elements allow for a three dimensional consideration of the
structural system, including bending and shear effects on
displacements, as well as the interaction of bonded walls. A
numerical example of a multistory building loaded horizontally is
discussed. Bending moments and shear force distribution are shown,
including the displacements on each storey level. The analysis is
developed based on the linear elastic behaviour of the masonry,
although the proposed modeling can easily be extended to the non
linear behaviour of the material.
5.5) Weerapun Sriboonlue and John H. Matthys, Torsional Behavior
Of Reinforced Brick Beams, Journal of Structural Engineering, 1990,
Vol. 116, No. 6, pp1626-1647.
Laboratory tests of 21 reinforced brick masonry beams under pure
torsion are described. Also, an ultimate torsional strength theory
for brick masonry beams subjected to pure torsion is developed. The
study described has been undertaken to obtain information about the
behavior of reinforced brick masonry beams subjected to pure
torsion. Beam specimens are rectangular in cross section and
composed of two wythes of brick facings with a grout core
reinforced with varying percentages of steel. Three types of brick
are used with type S Portland cement lime mortar to provide
different ranges of the ultimate compressive strength of masonry.
Specimens are grouped into four series of tests in which the
reinforcement patterns were different between each series. An
ultimate strength theory is developed based on the failure
mechanism using elastic bending theory and transformation of the
cross section. Although comparison of the predicted ultimate
strength theory of beams under pure torsion to actual beam test
values show appreciable scatter, the results are predictable to an
acceptable degree of confidence.
5.6) Capozucca, R., Analysis of Pre-stressed Brickwork Masonry
Column under Shear Force, Tech. Report, I.S.T.C. University of
Ancona, Italy, 1991, pp. 215-227.
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27
In seismic areas the behaviour of masonry buildings is greatly
influenced by the presence of slender elements, like brick work
masonry columns, which reduce the bearing capacity to shear force.
Masonry buildings, in fact as typical shear wall structures linked
by floors, may even resist to elevated horizontal seismic actions.
The weakness of masonry column is often the cause collapse under
horizontal force. The stability of a brickwork masonry column is
due to the vertical load, but during the seismic action an elevated
value of load may cause an increase of bending as consequence of
P-d effect. In seismic area the pre-stressed technique is suitable
and the bending capacity column is increased. In this paper, the
theoretical behaviour of pre-stressed brickwork masonry columns was
analyzed by means of resistant bending moment-normal force diagrams
for reinforced section. Shear resistance and decreasing of
resistance due to P-d effect were also considered. Results obtained
by experimental tests on a full-scale brickwork pre-stressed column
were shown.
5.7) Anon., Standard Specification and Analysis for Masonry with
Rat-Trap Bond, Proceedings, South Zone Training Centre, Chennai,
India, 1992, pp.1-7.
Specifications for brick work in Rat-Trap for masonry structures
and its Labour and material analysis of cost-effective construction
techniques have been discussed in this report.
5.8) Andreaus, U., Failure Criteria for Masonry Panels under
In-plane Loading, Journal of Structural Engineering, 1996, Vol.122,
No.1, pp.37-46.
Failure of masonry panels under in-plane loading can be
attributed to three simple modes: slipping of mortar joints,
cracking of clay bricks and splitting of mortar joints, and middle
plane spalling. In this paper a suitable strength criterion is
connected to each collapse mode. In more detail, a frictional law
is associated with the slipping, which accounts for the shear
strength depending nonlinearly on normal stress ( modified
Mohr-coulomb criterion of intrinsic curve). Splitting can be
expected by the maximum tensile strain criterion (Saint venant),
orthotropic non symmetric elasticity being assumed for the
material. Eventually panels exhibit spalling when the maximum
compressive stress (Navier criterion) is attained under biaxial
loading, Strength parameters are then identified on the basis of
experimental results and a comparison with the reliable criteria
found in the literature is carried out. The validity of the
proposed failure criteria to predict the experimental failure modes
in a non-dimensional stress space, normalized with respect to the
normal stress, has been tested in a qualitative manner for the
three fundamental failure modes. A quantitative comparison between
experimental and analytical results has been carried out for the
cases where significant scatters are concerned. The proposed
failure criteria seem to be in good agreement with experimental
results, within the limits of: small size panels, single withes,
solid units, regular mortar joints, and in-plane loads. Further,
these criteria can be used together with a suitable two dimensional
finite element model, and then directly used to carry out the limit
analysis of masonry walls, modeled by a discrete number of panels
of finite size. The potential application of the proposed criteria
to actual cases is also illustrated. In fact, a specific example is
worked out to show how to apply these criteria to predict the
failure load failure mode of a particular masonry panel.
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28
5.9) S. Briccoli Bati, G. Ranocchiai and L. Rovero, Suitability
of micromechanical model for elastic analysis Of masonry, Journal
of Engineering Mechanics, 1999, Vol. 125, No. 8, August, pp
09220929
A micromechanical model is proposed for determining the overall
linear elastic mechanical properties of simple-texture brick
masonry. The model, originally developed for long-fiber composites,
relies on the exact solution due to Eshelby and describes brickwork
as a mortar matrix with insertions of elliptical cylindershaped
bricks. Macroscopic elastic constants are derived from the
mechanical properties of the constituent materials and phase volume
ratios. Conformity of the suggested model to real brickwork
behavior has been verified by performing uniaxial compression tests
on masonry panels composed of fired bricks and mud mortar.
Composite masonry panels of varying phase percentages were then
constructed and tested by replacing several of the fired bricks
with mud bricks. Comparison of experimental results with
theoretical predictions demonstrates that the model is suitable
even in the presence of strongly differentiated phases, and is
moreover able to predict different behavior as a function of phase
concentration. The model fits experimental results more closely
than the micromechanical models previously reported in the
literature.
5.10) Vafai, A., Hamadi, M and Ahmadi, G., Numerical Modeling of
MDOF Structures with Sliding Supports Using Rigid-Plastic Link,
Earthquake Engineering and Structural Dynamics, 2001, Vol.30,
pp.27-42.
In this paper the responses of multi-degree-of-freedom (MDOF)
structures on sliding supports subjected to harmonic or random base
motions are investigated. Modeling of the friction force under the
foundation raft is accomplished by using a fractious rigid link
which has a rigid-perfectly plastic material. This will results in
identical equations of motions for the sliding structure, both in
the sliding and non- sliding (stick) phase which greatly simplifies
the implementation of the method in to a numerical algorithm. In
this model the phase transition times are determined with high
accuracy. This has two advantages: first, it prevents the so-called
high frequency oscillation of the relative velocity at the end of
the sliding phase and second, the time steps can be selected so
that each falls exactly within one phase of motion. In this case,
the stiffness matrix of the structure remains constant throughout
each phase and thus any method for solving the nonlinear
differential equations of motion (e.g : Network method ) can be
used without iteration. The proposed method, besides its
simplicity, is numerically very efficient and considerably reduces
the required analysis time compared with most of the other
methods.
5.11) Zhang, X., Singh, S.S., Bull, D.K and Cooke, N.,
Out-of-plane Performance of Reinforced Masonry Walls with Openings,
Journal of structural engineering, 2001, Vol.127, No.1,
pp.51-57.
The Out-Of-Plane performance of partially grouted, reinforced
concrete masonry walls subjected to simulated seismic loading is
investigated. The three full scale walls, with and without
openings, were constructed from 190 mm thick concrete blocks and
were 9.00 m long and 2.40 m with two 2.50 m long return wa