Bamboo Information

Slide 1

bamboo

a building material

Compiled by Architect Sudhanva Kolhatkar

Credits: VENU BHARATI by Vinoo Kaley

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Architect Sudhanva Kolhatkar.

Bamboo a plant of utilitarian value since ancient times

The first direct reference to bamboo in our literature

Rig-Veda (circa 3000 B.C.)

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An eco friendly material

The fastest growth rate

Reputedly the fastest grower of the living world, bamboo has clocked a record of 1.19 meters of vertical growth in 24 hours. It also ranks second in energy conservation rate with the mature Timber yields within five years of plantation

A general description of bamboo

Within the broad geometry of a noded pipe (It used to be called hollow timber by the 15th century Germans before they imported the word bamboo from India) bamboo stems possess shapes, sizes and colours in enormous diversity.

Among the 125 bamboo species of India there are some Himalayan ones which equal a human finger in diameter and measure up to the human height on full growth

On the other hand, WORRA is a species which at times measures 30 cm in diameter and over 30 meters in height.

Colour: As a rule Bamboos start their life green in colour, some light and some dark. As they mature, they start turning yellow. A gardener's favourite striated variety shows off brilliant green vertical lines like a bar code. There is a bamboo having dark (almost black) green hue or another one with panther spots on it known as tiger bamboo.

Shape: Usually hollow cylindrical although some are almost solid with a very small hollow. Some display a serpentine curve or there is another one the Buddha Bamboo with each internodes plumping out.

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The Rhizome

The bamboo shoot that we see growing above the ground is in technical terms a branch while the real trunk lies under ground, formed by hundreds of ginger shaped elements attached to each other.

The Sympodial trunk:

All tropical bamboo varieties have this multiple ginger shaped trunk arrangement. This bamboo grows in the form of an expanding circle above ground to maximize the exposure to sun.

The Monopodial trunk:

In the frost prone temporal zones of the Bamboo world like parts of China and Japan, one comes across a type of bamboo that has a trunk growing horizontally below ground and looks similar to the branches rising up. The growth is in a straight line and is also known as Military Bamboo in popular slang.

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Some common Indian Bamboos:
Name of BambooCulm Length (m) Dia. (cm)Internodes (cm)HabitatPropertiesUsesBambusa Arundinacea15-30 4-725-45Large parts of India. Kerala, Karnataka, Maharashtra, Orissa, Bengal, Assam and ManipurThin walls, Hard swollen nodes, Great hollows lower gross density and increase transportation costWoven products. Structural timber (used as whole)Bambusa Balcoa16-238-1520-45Nagaland, Meghalaya, Tripura, Assam, Bengal, Bihar, Utter Pradesh.Thick walls, only 1/3rd hollows, Vulnerable to borer attacks so one year curing in water immediately after felling is a mustBuilding timber, Scaffolding materialBambusa Multiplex2-41.5-3.520-40North east, AssamVery denseFurniture making, Natural live fenceBambusa Nutans6-134-725-45Tarais and Gangetic Belt, East of Yamuna, OrissaStraight culms with medium thick wallsCraft work as well as building timberBambusa Pallida13-205-815-70Above 700 to 2000 mtr. altitude; Mizoram, Meghalaya, Nagaland, Sikkim, Tripura, BhutanSoft nodes, Straight culmsVariety of uses
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Some common Indian Bamboos:
Name of BambooCulm Length (m) Dia. (cm)Internodes (cm)HabitatPropertiesUsesBambusa Polimorpha16-268-1540-60Forest species: Arunachal, Meghalaya, TripuraOutstanding Engineering propertiesAny general applicationBambusa Tulda7-235-1040-70Assam, Meghalaya, Mizoram, Tripura, Bihar and BengalVulnerable to borer attacks so one year curing in water immediately after felling is a mustBuilding timber, Scaffolding materialBambusa Vulgaris8-205-1030-45North eastern statesPrefers moisture and nutrient soil. Considered equivalent to the most durable of timbersConstruction material, Scaffolding, FencingDendrocalamus Brandisi19-3313-2030-40Manipur , Andaman, Coorg, KeralaLarge size makes it favourite of house buildersConstruction material, Handicrafts Dendrocalamus Giganteus24-3020-3035-90Arunachal, Assam, Manipur, Nagaland, West Bengal, CoorgLarge size offers various possibilitiesHousing timber, Masts of ships and many other usesGigantochloa Rostrata5-82-520-30Assam, Meghalaya, Mizoram, Tripura, Bihar, Madhya Pradesh, MaharashtraGeneral Purpose BambooMelocanna Baccifera10-203-720-50North eastern statesRod like CulmWeaving, fine work, windows, doors and grillsPseudo- Oxytenanthera Stocksii9m2.5- 415-30North west Karnataka, Konkan and Goa regionGeneral Purpose Bamboo
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Anatomy

Once out of the soil cover, Bamboo shoot goes up as a speed unrivalled in the organic world. During this growth phase of 2-3 months it rises 30-60 cm over a day to reach its full height, which may in some species exceed 30m.

The culm attains its full growth within a period of 1 to 3 months with all the branches and leaves. As illustrated (1,2,3,4), the culm tapers towards the top to answer the stresses it has to withstand swaying on high winds. The wall also goes on thinning towards the top to reduce the weight and thereby the incidental bending stresses the bottom internodes have to negotiate. Nature compensates this thinness of wall sections by relatively extra strong fibers.

Sheath is an extremely hard, paper thin membrane on the inner nodes protecting the shoot when it moves through the soil till it emerges into the open. A sheath is used as an important and reliable indicator of the age of the culm.

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Anatomy

A node is an invariable feature, characteristic of bamboo. At the node, a diaphragm connects the inside of the tube where the fibers from the two internodes intertwine into each other. The diaphragm strengthens the pipe with an appropriate counter structure in order to take bending stresses induced by the cantilever load of branches. Some species have prominent and swollen nodes while in the case of a few favoured species, they are barely visible.

The lowest quarter of the bamboo culm has the highest density of fibers which get distributed in the branches. Whenever one wants a high strength performance one goes for sections with high fiber density.

The skin: Unlike trees, bamboos do not have any bark but has a skin that protects the culm from the elements, insects and animals. Fortified by silica, the skin has a glass like gloss and waxy smoothness which protect the culm from those hazards. However it takes years for the skin to harden and in the first year one can conveniently mark the birth year of the culm by ones finger nails.

All the fibers and veins in bamboo run straight except at the nodes. This makes it very easy to work the bamboo on one hand and on the other to push water or treatment liquids through it.

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Some Traditional Uses of Bamboo

Acupuncture Needles

Airplanes

Animal Pens

Baskets

Bamboo Beer/ Wine

Beer Mugs / Cups

Blow guns

Bone setting

Bridges

Brushes

Bullock Carts

Buckets

Candle stands

Chicken Coops

Comb

Cooking Vessels

Crutches

Cutlery

Dry Cells

Fans

Fencing

Flute

Food

Fishing

Furniture

Garden Stakes

Grain Storage

Hats, caps

House Construction

Walls

Doors

Windows

Kites

Kanvar

Ladders

Looms

Manure

Medicine

Musical Instruments

Paper

Raclks

Rayon

Retaining Walls for open wells

River Bank Protectors

Roofing tiles

Room Dividers

Scare Crows

Scaffolding

Screens

Silk worm rearing

Toys

Gotam

Crackers

Bow Catapult

Trays

Tube Wells

Water Lifting

Water supply

Wind Chime

Winnowers

Wind Mills

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Traditional Houses in Bamboo

Typical Mizo house is stilted on bamboo stilts. Walls, floors, roofing, doors windows, Railings etc are all made in bamboo.

Typical walls

Typical Mizo door

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Typical Assam House a colonial adaptation is a frame structure with main beams and columns of timber while infill panels in bamboo mat and lime or mud plaster from both sides of mats

Traditional Assamese house is much different from so called Assam house

The plinth is about 25 to 30 cm above the surroundings. Bamboo verticals are stacked about 75 cm apart all along the external wall to take the roof load. Usually another row of bamboos is added to form the verandah which is the soul space of a tropical house. Thick stripped bamboo mats are then mounted on the vertical duly braced by stiffeners on either side and bound by ropes. The roof is usually made out of Pre-fab panels. The panels are formed of straw sandwiched between bamboo slivers. These prefabricated panels are then mounted over the bamboo rafters and tied to them.

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Gandhijis house at Sevagram Ashram

Gandhiji understood the importance of tradition much beyond nostalgic parochialism. He encouraged the Seva gram ashram to be built with ingenious innovations.

The window shutter shown below also doubles up as a sun shade

The lightness and high strength of bamboo culm receive appreciation from local building tradition. The door shown below is seen in Kolam houses all around. It is an intelligent use of hollow core of bamboo.

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Comparative Engineering Indices
ItemDensityMoisture %Moment of Resistance kg/cm2Modulus of Elasticity kg/cm2 Max. Crushing strength kg/cm2ReferenceBamboo SpeciesD. Strictus0.71910.71184159490645Shekhar & Gulati 1973B. Bambos0.65115.567465000483Gulati & Singh 1989B. Nutans0.71616.054585000508B. Tulda0.8210.01448176000-Hek 1956Timber SpeciesTeak0.60412.0959119600532Saal0.70712.01318162045641Mild steel7.80165021000004250
In case of a whole bamboo culm, owing to its tubular cross section, the actual mechanical strength goes up ever more. After all it is a natural pipe and one knows that a pipe is stronger than a solid section of the same weight in any material.

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Comparative Energy Expenditure to carry the same field load
MaterialDensityKg/m31Energy required in Mega JoulesMJ/Kg2 1x2= 3Field stress carriedKg/cm24Energy Index3/4 = 5Concrete24008.0192008024.00Mild Steel780030.02340001600146.25Timber6001.06001540.00Bamboo6000.53001202.50
Source: Dr. Jules Janssens paper Mechanical Properties of Bamboos International Bamboo workshop, 1985, China.

The Table shows clearly the extremely low expenditure of energy in bamboo production to carry the same field stress. These figures have been drawn from energy intensive bamboo farming practices of the West and would become ridiculously low under Indian conditions
MaterialDensityKg/ltr1Compressive StrengthKg/cm22Strength/ Weight Ratio2/1=3Stiffness FactorBamboo0.71964589733Teak Wood0.60453288018Mild Steel7.800425054427
Comparison of some engineering materials: Strength to Weight Ratios & Stiffness factors

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If the engineering properties of bamboo are as good as that of mild steel then is it possible to use it as a reinforcement in reinforced cement concrete?

For the last 50 years people have thought this possible as a revolutionary invention. Especially during the second world war when steel and cement were a black market commodity, the idea of replacing mild steel with high tensile strength bamboo took shape.

The idea almost hypnotized people.

But almost all the experiments failed under field conditions.

The reasons for failure are simple scientific facts.

Bamboo and Concrete fail as a composite material because:

Unlike mild steel, Bamboo strips posses no natural bond with concrete.

This can be partially countered by keeping the node pieces intact

When bamboo strips stay submerged in green concrete, it expands with high moisture absorption.

When curing is over and the concrete dries out, bamboo shrinks differentially breaking whatever bond has formed.

This causes cracks through which water enters under external application and matters go simply out of hand.

Bamboo

Reinforced

Concrete

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Bamboo is an organic material containing starch.

It can decay and is vulnerable to various pest attacks

Common agents of destruction are:

Fungi

Borer Beetles

Termites

The main reason for the decay or pest attack on bamboo is the presence of starch in the culm.The removal of starch (known as seasoning) can be done in various ways-

Preservation of Bamboo

Kinks in the armour:

The skin of bamboo does not allow free access to insects or microbes. The agents of decay/ destruction enter through: Cross sectional exposure and the branching points. If one can seal these accesses after bringing about a gradual drop of moisture to a safe 12%, there should not be much to worry about for whole culm users.

Heat Treatment: A preservation technique using castor-seed oil before scorching to an even brown on a wood fire.

Water seasoning: Submerging

under flowing water for 3 months

immediately after felling.

Smoke Seasoning: Not very common, smoke seasoning is done by some tribes using special herbs

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Chemical Treatment: Most natural preservation methods offer some protection from borers but only marginally against fungus and none against termites.

For construction purpose where intimate contact with earth is unavoidable, chemical treatment is a must. Location of use, green colour (or otherwise) of the stems and ultimate application are important determinants of particular process choice.

Preservation of Bamboo

Chemical Treatment is done either by smearing or by penetration

Smearing is done best on dry bamboos. The materials used for smearing are:

Lime

Tar (Molten / Dissolved)

Creosote

Acid chrome copper / copper chrome Boron, 2.4% solution.

Penetration is done in different ways. Bamboo veins are straight. Liquid at a pressure moves along the stem at an unbelievable speed, reaching each tissue. There are three methods to achieve penetration:

Steeping : The stems with branches and foliage intact are made to stand vertically up in a drum in a sun lit location. The chemical solution in the drum is absorbed by the tree in the process of photosynthesis.

Dipping : If freshly cut bamboos are immersed in the solution in a tub for sufficient time, similar penetration can be affected.

Boucherie : The preservative solution takes the gravity path instead of depending entirely upon the rather weak bio-pumps. In freshly felled bamboos, the distribution gets achieved in two hours flat.

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Some typical joinery details of bamboo:

Ladder Joinery

Joints using nut and bolt fasteners

Joints using nut and bolt fasteners

Do not nail bamboo, instead use drill for drilling a hole

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Some typical joinery details of bamboo:

Bamboo to bamboo

Using wood joint

Using M.S. pipes

Bamboo dowels

Bicycle rivetting

FRP Bandage

FRP Bandage

Bamboo to bamboo

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Some traditional joinery details of bamboo:

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SOME TYPICAL ARCHITECTURAL APPLICATIONS

National Institute of Fashion Technology, Kangra, Himachal PradeshNMBA has designed classroom structures for NIFT

National Institute of Fashion Technology has opened a centre at Kangra, Himachal Pradesh. In this regard NMBA has erected classroom structures at their centre at Kangra, Himachal Pradesh, by using engineered bamboo products in their premises.On the basis of their requirement NMBA has designed twelve class room structures of size 32x26 incl 6 verandah having bamboo composite framework & engineered bamboo based false ceiling & wall panels. These structures have been well appreciated by NIFT authorities and are already in regular use.

SOUTH CAMPUS (DELHI UNIVERSITY)NMBA has designed a canteen structure for Delhi University.Delhi University is in process of massive expansion of infrastructure like classrooms, hostels, cafeteria and other facilities. In this regard on demonstration basis NMBA has erected a canteen structure at South Campus by using engineered bamboo products in their premises for the showcase. On the basis of their requirement NMBA has designed a canteen structure of size 32x84 having steel framework, Bamboo jute composite roofing sheets & engineered bamboo based false ceiling & double wall panels.This structure has been well appreciated by Delhi University authorities and become a attraction for the outside personal visiting the place. Delhi University Now decided to maintain the surrounding area of canteen by using the bamboo and bamboo based material. They want to have incorporated Bamboo flooring tiles for canteen flooring with bamboo fUrniture, which is under progress.

STRUCTURES FOR 96TH INDIAN SCIENCE CONGRESS, SHILLONG96th Indian Science Congress had been held from 3rd Jan. to 7th Jan. 2009 at North Eastern Hills University, Shillong, Meghalaya for which 50 nos. of one room set (22'x12'), 50 nos. of two room set (32'x24') & 10 nos. of dormitories (60'x20') had been constructed in cluster by using Engineered bamboo based materials for the accommodation of 550 delegates for the conference. These structures will be utilized for the accommodation for the future upcoming conferences/seminars and faculty.

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SOME TYPICAL ARCHITECTURAL APPLICATIONS

BAMBOO BASED POLYHOUSE (Sikkim)

Use of polyhouses to ensure controlled environmental condition for growing flowers and vegetables, is on the rise during last few years. Using bamboo as structural material in polyhouses is new application segment, which we are trying to be modeled on our experience, gained by using whole bamboo in various buildings erected throughout the country. The use of whole bamboo with necessary emphasis on treatment, jointing and aesthetics were to be highlighted. This segment has potential for value added applications of bamboo by utilizing its inherent structural strength as well as by ensuring cost competitiveness vis--vis steel based polyhouses.

An innovative design using natural material like Bamboos slashes the setup costs of green house by half. As a renewable resource like Bamboo is used instead of steel, the polyhouses so built help mitigate global climate change. The use of Bamboo also provides income to the rural economy.

NMBA has collaborated with M/s Thousand Petals for the construction of bamboo based polyhouses at many places. 2000 sq mt size polyhouse has been constructed at G.B.Pant University, Pantnagar. Various sizes of Bamboo based polyhouses has also been constructed for demonstration in Sikkim and West Bengal.BOAT HOUSE RESORT (KUDAL, Maharshtra)

An innovative use of bamboo and their by product has been shown for the construction of Boat house at Kudal, district Sindhudurg in Maharashtra. In the structure vide variety of structural application of bamboo (whole, split and engineered bamboo products) can be seen having architectural innovative ideas. The structure has been built by KONBAC

TYPICAL INTERIOR APPLICATIONS

BAMBOO BLINDS

BAMBOO FLOORING

BAMBOO BOARDS

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Agencies
Mr. Rahul SaksenaChief Executive BASERAAdd:Basera, Kerwa Dam Road Bhopal,Tel:0755-5234731Fax:0755-2696832Email:[email protected]/CIBARTCentre for Indian BambooResource and TechnologyAdd:200, Jor BaghNew Delhi 110003Tel:24604404/34Fax:24648303E-mail:[email protected]. S Kumar,PresidentMr. Madan,Vice PresidentMobile:9418089248Mr. K Dutt,SecretayDhauladhar Public Education SocietyAdd:Yol Cantt, DharamshalaDistt-Kangra, H.P.Tel:01892-236600, 236273Email:[email protected]@rediffmail.comMr.Subhendu MitraGeneral SecretaryForum of Scientists,Engineers & TechnologistsAdd:15N, NelliSengupta Sarani,New CMC Building (5th Floor)Kolkata-700087Tel:033-22529675Fax:033-22520521Email:[email protected]. MahapatraRural Womens Building CenterAdd:Gruhanirman Bhawan,Gandhi Vihar, Po-ArikamaDist.-Khurda, OrissaPin:752064Mobile:09437012290Tel:0674-2332290Email:[email protected]. Vinai SharmaCoordinator (Projects)Vasundhra Rural BuildingCentreAdd:319, Teachers Colony,Faridpur (Bareilly)-243503 U.P.Site Add:286 KM, Mile Stone,NH-24 Faridpur (Bareilly) U.P.Tel:05821-224306,011-26941626Mr. Suneel DeshpandeSecretarySampoorna Bamboo KendraAdd:Lavada, District DharaniMaharastraTel:091-7226-24662/ 24522Fax:091-7226-24391Ms. Niharika SinghVice presidentRaghvendra Rural Developmentand Research OrganizationAdd:17 KaiserbaghLucknow-226001, (U.P.)Tel:011-265927701.IS 1902:1993Code of Practice for preservation ofbamboo and cane for non-structuralpurposes2.IS 6874:1973Methods of test for round bamboos3.IS7344:1974Specification for bamboo tent bamboos4.IS 8242:1976Methods of tests for split bamboos5.IS 8295 (Part 1): 1976Specification for bamboochicks: Part 1 Fine6.IS 8295 (Part 2): 1976Specification for bamboo chicks:Part 2 Coarse7.IS 9096: 1979Code of practice for preservation ofbamboo for structural purposes.8.IS 10145:1982Specification for bamboo supports forcamouflaging Equipment.9.IS 13958: 1994Specification for bamboo mat boardfor general purposes10.IS 14588: 1999Specification for bamboo mat veneercomposites for general purposes11.IS-15476: 2004Bamboo mat corrugated sheets12.IS 5913:Durability including water absorption,impermeability, load bearing capacity,density, frost cracking etc.13.IS 4908: 1968Random sampling.14.IS 459: 1992/ASTM-D1037Standard for accelerated aging.15.UV Resistance testLamp UV-B Cycle: 4 hours exposureat 60C followed by 4 hrs humidityexposure at 50C.16.IS 4990: 1993Ply wood for concrete shuttering.17.ISO 22156: 2004Bamboo structural design18.ISO 22157: 2004Bamboo physical and mech properties.19.IS 2752: 1995IS 8366: 1989IS 877: 19891. Activated carbon specification (granular).2. Activated carbon specification (Powder)3. Sampling and test of activated carbon.
I.S.Codes for structural use of bamboo

National Mission On Bamboo ApplicationsVishwakarma BhawanShaheed Jeet Singh MargNew Delhi - 110016Tel: +91-11- 26566778Fax: +91-11- 26962267e-mail:[email protected]

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The price of abamboo unfinished floorwill often appear to be very cheap on the face of things, and typically such floors may start at prices around the Rs. 75.0 s/f level. One thing to bear in mind with this type is the fact that the cost of finishing the floor and the extra labor involved is likely to add a hefty sum to the final total, regardless of whether or not you carry out the install yourself. This is due to the cost of the additional materials needed, and possibly tools, to sand, stain and coat the flooring.

Next on the price scale will be standard finished bamboo flooring. This is a very broad range with a lot of choices and prices that vary from around Rs.100 to Rs. 300 per s/f. The main factors that will influence the price you pay are the quality of the finishing, the length of the warranty and whether the floor is a snap lock one or a straight edged plank floor.

The Affect that the Coating has on the Price Some coatings, such as Klumpp, are certified to be low in formaldehyde but they do cost more to produce. It is important that you don't simply choose a bamboo floor because it has the lowest price especially if the coating on it is likely to adversely affect your health in the long term.

Bamboo flooring planks that have been manufactured with click lock or snap lock joints may well be priced higher than those without. The amount of work you are prepared to put into the installation will be the deciding factor in this regard. Clearly snap lock floors are much faster to lay and may well be worth paying a slightly higher price for.

Present pricing of bamboo flooring

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Conclusions

Bamboo is one of the worlds best engineering materials

Bamboo is one of the worlds most eco-friendly construction materials.

Bamboo is the worlds fastest grower

Bamboo is the worlds second best photo converter and at a much less water cost than the first

Bamboo plantation enriches the soil, arrests soil erosion and tames flash floods

Bamboo offers stakes to trees, fodder to animals and food to humans

Bamboo is recurringly harvestable with first mature stems in 5-6 years of plantation

Credits: Venu Bharati by Vinoo Kaley

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Bamboo Information

Documents

bamboo world

word bamboo

tiger bamboo

military bamboo

type of bamboo

buddha bamboo

bamboo species of india

india bamboo stems