Interim Report

Fabrication and Testing of Jute Reinforced Engineered Bamboo Structural Elements

Dr V M Chariar

Centre for Rural Development and Technology Indian Institute of Technology Delhi

November 2009

Fabrication and Testing of Jute Reinforced Engineered Bamboo Structural Elements

Abstract

The indiscriminate infrastructural growth is leading to rapid environmental

degradation. Steel, cement, synthetic polymers and metal alloys used for construction

activities are energy intensive as well as cause environmental pollution during their

entire life cycle. To address this issue, research on non-polluting materials and

manufacturing processes have been taken up in the recent years. In this context, use of

bamboo which is fast growing and ecologically friendly material for structural

applications especially in a tropical country like India is being considered as quite

appropriate.

Studies show that steel requires 50 times more energy than bamboo to produce a

material equivalent of 1 m3 per unit stress. The tensile strength of bamboo is relatively

high and can reach up to 370 MPa. This makes bamboo an attractive alternative to steel

in tensile loading applications. This is on account of the fact that the ratio of tensile

strength to specific weight of bamboo is six times greater than that of steel. Therefore, in

this study it has been attempted to develop engineered bamboo structural elements for

use in rural housing. Bamboo slats derived from bamboo poles have been assembled

ined together and these are treated with epoxy to bring about structural bonding and

strength. Jute fabric as a reinforcement to improve the mechanical properties of

Engineered Bamboo Structural Element (EBSE) has been attempted under this study.

Table of Contents

1. Introduction 1

Problem Definition and Objectives 2. Literature Review 5 3. Experimental Method 8

Equipments Materials

4. Fabrication of EBSE 13 5. Properties Evaluation of EBSE 15

Tests on EBSE Beams Tests on EBSE Columns

6. Results and Discussions 21 7. Applications of EBSE 23

8. Conclusions 27 References 28 Annexure-I 29

1

Chapter One

Introduction

Indiscriminate infrastructural growth is leading to rapid environmental degradation.

Steel, cement, synthetic polymers and metal alloys used for construction activities are

energy intensive as well as cause environmental pollution during their entire life cycle.

To address this issue, research on non-polluting materials and manufacturing processes

have been taken up in the recent years. In this context, use of bamboo which is fast

growing and ecologically friendly material for structural applications especially in a

tropical country like India is being considered as quite appropriate.

Studies show that steel requires 50 times more energy than bamboo to produce a

material equivalent of 1 m3 per unit stress. The tensile strength of bamboo is relatively

high and can reach up to 370MPa. This makes bamboo an attractive alternative to steel

in tensile loading applications. This is due to the fact that the ratio of tensile strength to

specific weight of bamboo is six times greater than that of steel. Therefore, in the study

it has been attempted to develop engineered bamboo structural elements for use in

rural housing.

There are about 1500 species of bamboo. Some are much stronger than others.

Bambusa asissi and Dendrocalamus strictus are extremely strong. Guadua is extremely

tough. Some herbaceous bamboos are no stronger than reed. Some bamboos have very

thin walls but grow to larger diameters. Matching the bamboo to the application makes

for greater success.

The weakest direction of bamboo is perpendicular to the axis and tangent to a circle or

within the wall. Many applications of bamboo do require splitting the bamboo, making

this tangential weakness a real blessing. The fibers of bamboo can be pulled apart from

each other easily. Between the strength of longitudinal compression and low tangential

2

strength is the shearing force, when the fibers resist sliding past each other in direction

that they grow. The ability to withstand twisting forces is fair.

During the 1980's, the International Development Research Center (IDRC) began to take

note of people's reliance on bamboo. International wildlife expert Jane Stevens observes

that strong IDRC support for bamboo research has resulted in funding to the tune of

about 10 million dollars, used for national research programs involving more than 600

scientists and engineers in 14 nations (Stevens). These studies and experiments have

helped define the capabilities and strengths of bamboo, with the additional goal of

improving bamboo to make it a more competitive resource.

Table 1 Comparison of Bamboo with different construction materials

Use of bamboo is placed to address the four major global challenges:

• Shelter security, through the provision of safe, secure, durable and affordable

housing and community buildings.

• Livelihood security, through generation of employment in planting, primary and

secondary processing, construction, craft and the manufacture of value-added

products.

• Ecological security, by conservation of forests through timber substitution, as an

efficient carbon sink, and as an alternative to non-biodegradable and high-

embodied energy materials such as plastics and metals.

3

• Sustainable food security, though bamboo-based agro-forestry systems, by

maintaining the fertility of adjoining agricultural lands, and as a direct food

source, for example bamboo shoots.

1.1 Problem Definition and Objectives Although potential of Bamboo in use as a construction material has been well defined,

but this is limited by its non-uniformity. The diameter, wall thickness, inter-nodal

spacing of bamboo all vary substantially even in a single bamboo of 2m to 4m length.

While working with bamboo duly taking into account its individuality may be

aesthetically and artistically satisfying, often the risk of the cost of the end product

being pushed far beyond the commoner’s reach is a sad reality. The current work puts

forward the concept of Engineered Bamboo Pipes which solve this problem of non-

uniformity of bamboo pipes. Since Bamboo is plentifully available in the selected area,

and efforts are on to increase its production, successful demonstration of this

technology would result in applications that have not been hitherto pursued.

The purpose of developing bamboo products is to provide environmentally sound

construction alternatives to conventional construction materials, develop the rural

bamboo processing industry to increase income of rural people and also to improve safe

guard the environment. The EBSE elements can be used as substitute for concrete, steel

and wood used in housing and other products required in the day to day applications.

This project explores the use of jute reinforced EBSE elements using low cost production

process. Bamboo slats derived from bamboo poles have been both joined together and

these are treated with epoxy to bring about structural bonding and strength. Jute fabric

as a reinforcement to improve the mechanical properties of Engineered Bamboo

Structural Element (EBSE) has been attempted under this study.

Apart from non-uniformity, the applications of bamboo as an engineering material are

limited on account of difficulty arising in gripping and joining bamboo. If features of

uniformity, grippability and weldability are imparted to bamboo, the novel engineered

4

bamboo structural elements would be beneficial in multi-fold ways. It could find

applications in readily deployable columns and beams for construction, temporary

shelters, low-cost public shelters etc. These would function as prefabricated structural

units which can be mass-produced and assembled easily for construction of housings,

requiring little time, specialized skills and monetary input. Thus, these may be

employed for quick-shelters in calamity hit areas. Moreover, availability of EBSEs

would facilitate use as column elements in rural construction.

Also, several small entrepreneurs and fabricators in rural areas are looking to replace

steel with a low cost material. As a result of this technology, the small business of

replacing steel with bamboo which is impeded by the structural non-uniformity of

bamboo would get a boost. This would lead to wealth generation in the rural economy

and creation of several micro-enterprises. Once the technology is available in the field,

the same would be popularised. This would lead to the technology replicating widely

leading to value-addition and utilization of bamboo for high-end applications.

Entrepreneurship and employment generation activities would be sustainable.

The objectives of this minor project are;

• Fabrication of Jute Reinforced Engineered Bamboo Structural Elements • Flexural and Compression Testing of Engineered Bamboo Structural Elements

• Exploration of utilising Engineered Bamboo Structural Elements for housing

This minor project report has been divided into sections such as Literature Review,

Methods and Materials Used, Results and Discussions, Applications of EBSE,

Conclusion and References. The section on methods and materials used has detailed

descriptions on the materials and equipments used, fabrication process and testing

procedures, adopted in the EBSE production and testing procedures followed. The

analysis and basis for the calculations are provided in the last section as Annexure.

5

Chapter Two

Literature Review Increasing global populación has significantly increased the demands of sustainable

building materials. A report reveals that currently about 1.4 million housing units are

built and it represents 55-60% of all the environmental impacts. It is also said that more

than 40 trees are required to build a good size wood frame house. The increased

demand of timber has caused global deforestation at the rate of 0.2% annually of the

total forest area that accounts for 7.5 million hectares of the forest.

Ghavami.[1] points to the use of bamboo to be superior than other construction

materials and their use in eco-construction and infrastructure especially with regards to

the choice of non-conventional materials and technologies, which are used not only in

developing countries, including Brazil. Bamboo has been found excellent building

material due to its versatile characterises. It is estimated that more than a billion people

live in bamboo houses mostly in developing worlds. Additionally, its ecological and

economical characteristics have made it a sustainable building material. Ghavami. [2]

Various testing, researches and practical experiences have revealed that bamboo has

high tensile strength, high strength to weight ration and high specific load bearing

capacity. Due to its long, strong and elastic nature of fibbers; bamboo is known as high

resistance to the earth quake. It has also natural insulation properties that would save

thermal energy and it is a very durable material if treated properly Bamboo is one of the

oldest and most versatile building materials with many applications in the field of

construction, particularly in developing countries. It is strong and lightweight and can

often be used without processing or finishing.

Alann. [3] proposes that durability and high variability among the properties present in

timber can be reduced by using glued-laminated timber. Investigations on various

reinforcement devices have been experimented to increase the strength of timber

structures. Lakkad. et al [4] studied the detailed mechanical properties of bamboo.

Mechanical properties of bamboo, mild steel, polyester resin and glass reinforced plastic

6

are compared. The mechanical properties of bamboo are found to compare favourably

with those for other reinforcing materials. As tensile strength of bamboo is greater than

that of resin, the author recommends bamboo fibre for reinforcement of plastic.

Typically, species like dendrocallamus giganteus (DG) have tensile strength of about

120 MPa, compressive strength of 55 MPa and Young’s modulus of 14 GPa. These

figures do not compare badly with mild steel which has an ultimate strength of 410

MPa, yield strength of 250 MPa and Young’s modulus of 200 GPa. Concrete has much

lower strength than those of bamboo reported here. In addition, the low density of

bamboo, which is typically 700 kg/m3, results in much higher strength to weight ratio

as compared to steel (density = 7800 kg/m3) and concrete (density = 2400 kg/m3). The

only shortcoming with raw bamboo is susceptibility to termite attack which can be set

aside by suitable chemical treatment.

Li. et al [4] has studied reforming the properties of bamboo using aluminium

composites. As the advantages of bamboo become well known, people are attempting

to experimentally build larger structures with bamboo. While there are many small and

temporary shelters made of bamboo, efforts are on to build larger and sturdier homes. It

is difficult for researchers to begin trial runs on bamboo homes due to existing

restrictions placed by the International Congress of Building Codes (ICBO). In Costa

Rica, engineers are developing safe ways to incorporate bamboo into household

structures. The country sponsored a National Bamboo Project in 1986 as a "new

technological approach to prevent deforestation in Costa Rica. The idea was to replace

the use of wood with an alternative, cost-effective, and seismically-sound building

material".

Bhalla et al [5] work on the use of bamboo as an engineered structural material, and sets

asides the conventional belief that only concrete and steel structures can be engineered.

In order to exploit fully the potential of bamboo as a construction material, various

structural components using bamboo concrete composites demonstrated them in

building houses using bamboo as a structural element, two bamboo arches vertically

7

separated are connected using Ferro-Cement Band ties to generate a Bow Beam Arch as

a load bearing member. Associated products such as bamboo based panels and bamboo

reinforced concrete also find applications in the construction process. In spite of these

clear advantages, the use of bamboo has been largely restricted to temporary structures

and lower grade buildings due to limited natural durability, difficulties in jointing, a

lack of structural design data and exclusion from building codes.

Studies have shown the potential of Bamboo in use as a construction material. But this

is limited by its non-uniformity. The diameter, wall thickness, inter-nodal spacing of

bamboo all vary substantially even in a single bamboo of 2m to 4m length. While

working with bamboo duly taking into account its individuality may be aesthetically

and artistically satisfying, often the risk of the cost of the end product being pushed far

beyond the commoner’s reach is a sad reality. The current work puts forward the

concept of Engineered Bamboo Pipes which solve this problem of non-uniformity of

bamboo pipes. Since Bamboo is plentifully available in the selected area, and efforts are

on to increase its production, successful demonstration of this technology would result

in applications that have not been hitherto pursued.

8

Chapter Three

Methods and Materials Used In order to fabricate and test jute reinforced EBSE as columns and beams, bamboo slats

derived from whole bamboo of “Bambusa Tulda” variety which is chemically treated

was obtained from the Bamboo Lab functioning at Micro-Model Complex of IIT Delhi.

These slats along with materials procured and developed from the market such as

wooden nodal plates, jute cloth, epoxy and nails were used to fabricate the EBSE

column and beam elements. The brief methodology adopted under the study is as

follows;

3.1 Equipments Used

• Bamboo Hydraulic Splitter Machine: It is used for splitting the bamboo to

required number of pieces. The machine is capable of splitting bamboo of

diameter 0.2 metre or 8 inches. Parallel or radial grills provided in the machine

enable splitting the operation. In case of board making plant, parallel edges are

required in for the bamboo splits. This can be achieved by using specially

developed grills. The grill has parallel blades, which split the bamboo to number

of pieces with nearly parallel edges. Grills with 'zero' centre can be used to split a

nearly solid bamboo. The machine also has the advantage to be paused at any

point of its operation, and thus even bent bamboo can be split, which increases

the productivity. Hence, the machine can be said to be able to split all types of

bamboo for both stick making and board making plants.

Fig: 1 Bamboo Hydraulic Splitter Machine

9

• Internal Knot cum Skin Removing Machine: The machine is designed to clean

the internal knot as well as the outer skin of bamboo. The machine uses

hardened chisels for the operation. Irrespective of the final product to be made,

the machine is a necessary part of any bamboo processing plant. There are two

chisels, one for removing the internal knot and one for removing the outer skin

of the bamboo split. In the process of cleaning the upper and the lower skin; the

output attains a flat surface on both the sides. This helps in further processing of

the splits. Maximum width of bamboo that can be fed 40mm, dimension of the

machine in meters 0.95X1X1.2, net weight 300kg, maximum material that can be

removed 10mm, power consumption 2.25kw or 3hp.

Fig: 2 Bamboo Internal Knot cum Skin Removing Machine

• Bamboo External Knot Removing cum Skin Finishing Machine: This is

designed to clean the external knot as well as the outer skin of bamboo.

Removing of the outer skin and knot is very crucial for further operations on the

bamboo. Their cleaning assures longer life of cutters and chisels. The machine

uses specially designed carbide tipped external knot removing cutter. The cutter

is dynamically balanced and is suitable for all sizes of bamboo, i.e. up to 200 mm.

The machine is unique in itself, as for the first time it has been that easy to clean

the outer skin and knot of the bamboo. The operator has just to rotate the

bamboo and move it along the axis, and the skin and knot are cleaned by the

cutter, smoothly. Material removal rate can be controlled by setting the stopper

and hence even bent bamboos can be machined.

10

Fig: 3 Bamboo External Knot Removing cum Skin Finishing Machine

• EBSE Machine: A manually operated special purpose machine was designed at

IIT Delhi to facilitate preparation of EBSE pipes and application of epoxy on the

element with ease. The unit has a resin bath, rotating shaft, shaft stand and a

handle for rotating the shaft after inserting the EBSE pipes to facilitate

application of epoxy coating.

Fig: 4 View of EBSE machine

3.2 Materials Used

• Bamboo Slat preparation: In order to prepare the EBSE beams and columns,

treated bamboos of “Bambusa Tulda” variety were cut into 1.35m and 0.45m

length sizes and their external knots were removed using “External Knot

Removing Machine”. Using the “Radial Splitting Machine” the bamboo was

splitted into slats later. Further, the “Universal Bamboo Processing Machine” is

11

used to smoothen the bamboo slats from three sides which includes both the

sides as well as the internal surface so that they can be easily assembled together

to form flat strips. A nominal size of 20mm width and 5mm thickness slats were

chosen for making the EBSE beams. For columns, a nominal size of 20mm width

and 7mm thick slats were used.

Fig: 5 Slats derived from whole bamboo

• Wooden Nodal Plates: The nodal plates are made up of normal country wood.

Size of the nodal plate is decided based on the desired dimension of the EBSE to

be fabricated. Nodal plates of 200mm dia and 20mm thickness have been used in

the study. A bore of diameter 45mm is provided at the centre of the nodal plates

to facilitate insertion of them on to the shaft assembly of EBSE fabrication

machine. For beams of 1.35m length, 3 nodal plates one at the centre and two at

the ends were provided. For columns of 0.45m length, 2 nodal plates at both ends

were provided.

12

Fig: 6 Nodal plates used for fabricating EBSE

• Jute Fabric: Jute Hessian also termed as Burlap which is a fine quality jute fabric

has been used as reinforcment. This is commonly used as packaging material for

all kinds of goods. It is a plain weave cloth made wholly of Jute with single warp

and weft interwoven weighing not more than 576 grms/m2.

Fig: 7 Jute Hessian used as Reinforcement for EBSEs

• Epoxy: Liquid epoxy Araldite (LY 556) having specific gravity 1.15-1.2, density

1.3 g/cm3 at 25ºC , flexural strength 110~120MPa, ultimate flexural elongation

5.5~6.5% , gel time of 600 minutes, with hardener Aradur (HY951) was used. For

each sample of laminated bamboo composite, the ratio of araldite and hardener

used was 100:23 by weight. A quantity of 200grams of epoxy was used per meter

length of the EBSEs fabricated under the study.

13

Chapter Four

Fabrication of EBSE

Using the manually operated special purpose machine designed for EBSE

fabrication, the EBSEs were fabricated. Nodal plates were inserted into the shaft of

the machine at centre and two ends for beams and at both end of columns. The slats

prepared were fixed to the nodal plates with a help of nails along with the jute farbic

one after the other. Reinforcment of jute is carried out according to the three designs

of reinforcement proposed under the study such as “outer, inner and alternate outer

and inner reinforcement”. After the initial development of the member, coating of

epoxy is applied uniformly using over the EBSE by fixing it on to the EBSE special

purpose machine. On rotation of the shaft, expoxy stored in the resin bath is

uniformly applied over the EBSE. Finally, finer finishing of the epoxy coating over

the EBSE surface is carried out by using a brush. The EBSE is later allowed to cure

before testing. For columns, a thick jute strap of 50mm wide was provided to have

confinement of slats at the outer edges as well.

Fig: 8 View of outer jute reinforced EBSE

14

Fig: 9 Sequence of Slat Preparation from Bamboo

Description EBSE Beams EBSE Columns

Span 1.31m 0.45m

Internal Dia 200mm 200mm

External Dia 213mm 217mm

No. of Nodal Plates 3 2

Location of Nodal Plates Ends (2) & Centre (1) Ends (2)

Type of Reinforcement EBSE Fabricated Provided

Internal, External, Alternate

- Total 3 nos.

Internal, External, Alternate & No Reinforcement - Total 4 nos.

Table: 2 Features of EBSE Beams and Columns Fabricated

15

Chapter 5

Tests on EBSEs

The EBSEs fabricated were subjected to both flexural and compressive strength tests

using Universal Testing Machine. The 3-point load tests for beams with a span of 1.31m

were carried out using a UTM to determine flexural strength and modulus of elasticity.

For the columns of 0.45m length, compression tests were conducted to determine

compressive strength and modulus of elasticity. Load and deflection values were

obtained for each specimen of the EBSE fabricated for the study purpose.

Fig 10 : View of Automatic UTM used for 3-point load test

5.1 Tests on EBSE Beams

The test for beams under 3-point load tests provided data for plotting the load versus

deflection curve. Maximum load and deflection was also obtained before failure of

beams under load (refer graphs given below). The following table provides, various

parameters obtained from the tests of EBSE beams.

Fig 11 : Testing of internal jute reinforced EBSE

16

Type of Jute Reinforcement

Provided to EBSE

Max.Load Deflection Flexural Strength

Modulus of

Elasticity

Internal 13.8KN 63.11mm 16.8MPa 3988MPa

Alternate -Internal

and External 4.6KN 151.11mm 5.6MPa 7929MPa

External 17.7KN 65.77mm 21.55MPa 3988MPa

Table 3 : Test results of EBSE Beams obtained under 3-Point Load Test

Graph 1 : Test result of internal jute reinforced EBSE

17

Graph 2 : Test result of alternate internal and external jute reinforced EBSE

Graph 3 : Test result of external jute reinforced EBSE

5.2 Tests on EBSE Columns The test for columns axial compression tests provided data for plotting the load versus

deflection curve. Maximum load and deflection was also obtained before failure of

18

columns under load (refer graphs given below). The following table provides, various

parameters obtained from the tests of EBSE columns.

Type of Jute Reinforcement

Provided to EBSE

Max.Load Deflection Compressive Strength

Modulus of Elasticity

Internal 92.84 KN 19mm 16.67MPa 4968.82MPa

Alternate -

Internal and External

82.98KN 14.3mm 14.90MPa 6036.9MPa

External 51.78KN 16mm 9.30MPa 4005.66MPa

No

reinforcement 68.78KN 14mm 12.35MPa 4893.80MPa

Table 4 : Test results of EBSE Columns obtained under Axial Compression Test

Graph 4 : Test result of non-jute reinforced EBSE (only with epoxy)

19

Graph 5 : Test result of internal jute reinforced EBSE

Graph 6 : Test result of alternate internal and external jute reinforced EBSE

20

Graph 7 : Test result of external jute reinforced EBSE

21

Chapter Six

Results and Discussions

The following are the interpretation of the experimental results exhibited by the EBSE

beams and columns during flexural and compression testes;

• Failure of EBSEs has been observed mainly due to brittle failure of Epoxy matrix

especially when tested as beams. Bamboo slats used for the element fabrication

were unaffected in the loading. Use of different grades of epoxy, study of

different types of reinforcement and joints between slats can provide further

details of the properties.

• Higher load carrying capacity was observed in EBSEs with jute reinforcement on

the outer surface. The beam carried a load of 17.7KN and a flexural strength of

21.55MPa. However, early failure of the column with outer reinforcement needs

further examination. This could be due to improper fabrication of the element

which has resulted in a early failure.

• EBSE having alternate reinforcement on inner and outer surfaces showed high

level of ductility without failure of the epoxy coating due to better bonding

strength. Modulus of Elasticity of both the beam (7929MPa) and column

(6036.9MPa) fabricated with this reinforcement was higher than other types of

reinforced EBSEs.

• Internal and External jute reinforcement of EBSEs showed higher load carrying

capacities while EBSEs with alternate external and internal jute reinforcement

showed greater ductility. The internal and external reinforced beams carried

about 13.8KN and 17.7KN loads respectively. The internal and external

reinforced columns carried 92.84KN and 51.78KN loads respectively

• Failure of EBSE columns nodal plates due to shrinking of the upper portion and

bulging of the body while the load is applied on the element was observed. Use

22

of high strength wood like teak in place of the country wood will help in

improving the load carrying capacity of the columns.

Fig 12 : Failure of Nodal Plate and Bamboo Slat Joints due to Bulging of Columns

• Use of square or rectangular jute EBSE for beams can help in increasing the load

carrying capacity with minimum deflection due to the increased surface area

available in the tension zones.

• Having both outer and inner jute reinforcements to EBSE will improve the load

carrying capacity due to increased bonding strength with the epoxy coating.

• The property of lower energy required for production and self weight of EBSEs

per unit stress developed can be a quite use element in the eco-housing

construction field in the future (Table-1).

• The advantage of fabricating EBSEs for a required strength is possible due to the

mechanical fabrication process adopted. By adjusting the diameter of the EBSEs

this can be achieved.

23

Chapter Seven

Applications of EBSE

The EBSE beams and columns can be used in rural housing due to their increased

mechanical properties and durability. These also can be used as elements of household

furniture and other articles used in the day to day life due to their aesthetic appearance.

Weldability and durability of EBSE can be taken advantage for using them in

construction and for other purposes mentioned above. The advantage of localised

fabrication of EBSE in a rural area itself provides opportunity for local employment and

reduction of fabrication costs.

The cost economics of the EBSE of 1m length was worked out keeping a small scale

industry level operation. This is given as follows;

Details  Amount (Rs.) 

Bamboo (30‐40 Feet) for preparation of slats  100 

Labour for processing  300 

Capital and running costs  50 

Nodal Plates (2nos.)  80 

Epoxy (200grams)  20 

Jute (1sqm)  20 

Total  570 

Table 5 : Cost Estimate of Fabrication of 1 m long EBSE of 217mm Outer Dia.

24

A schematic plan of rural house which can be constructed is given below;

Fig 13 : Plan at Foundation Level

Fig 14 : Plan at Plinth Level

25

Fig 15 : Framing plan at Truss level

26

Fig 16 : Final View of the Structure with EBSEs

27

Chapter Eight

Conclusions and Scope of Future work

EBSE beams and columns can provide tailored solutions to the eco-housing initiatives at

cheaper costs. However, further studies to achieve higher mechanical properties and

understanding their behaviours in detail would make this a reality. Further work on

weladbility aspects can provide solutions to the use of EBSEs in the actual construction

of houses in rural areas.

28

References [1] Ghavami K. Eco-construction and infrastructure. RIO 3 - World Climate & Energy

Event, 1-5 December 2003, Rio de Janeiro, Brazil. [2] Ghavami K. Bamboo as reinforcement in structural concrete elements. Department

of Civil Engineering, Pontificia Universidade Catolica, PUC-Rio, Rua Marques de Sa˜ o Vicente 225, 22453-900 Rio de Janeiro, Brazil, 2004.

[3] Alann A. Fibres for strengthening of timber structures. Research report. Luleå

University of Technology, Sweden. February 2006 [4] Ahmad M. Analysis of Calcutta bamboo for structural composite materials. Virginia

Polytechnic Institute and State University, 2000. [5] Lakkad S.C, Patel J.M. Mechanical properties of bamboo, a natural composite.

Fibre Science and Technology 14 (198(~81) 319 322. [6] Li, S.H., S.Y. Fu, B.L, Zhou, Q.Y. Zheng and X.R. Bao. "Reformed bamboo and

reformed bamboo/aluminum composite." Journal of Material Science 33, 1998, 2147-2152

[7] Bhalla S. Gupta S. Sudhakar P. Suresh R. Bamboo as Green alterative to concrete

and steel for modern structures. International Congress of Environmental Research, Goa, 18-20 December 2008.

29

Annexure-I

Contd…

30

Computation

Moment of Inertia Moment of Inertia of a hollow circular section can be found using the following equation;

Flexural Strength Flexural Strength can be determined using the equation given below in megapascals;

Contd..

31

Flexural Modulus

32