This document discusses the potential for bamboo as a replacement for steel in construction. It begins by outlining the high costs and environmental impacts of steel production. Bamboo is presented as a sustainable alternative that is inexpensive, widely available, and has properties comparable to steel. The document then provides details on the types and distribution of bamboo species globally. It compares the mechanical properties of bamboo to steel and other materials. The final sections cover techniques for selecting, preparing, and using bamboo for reinforcement in concrete, as well as advantages like lower carbon emissions and disadvantages like brittleness.

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BAMBOO AS A 21st CENTURY STEEL
Collaboration By :
SHAIKHMOHAMMAD FAISAL JAVEDALAM

2.  Abstract
 Introduction
 Bamboos
 Distribution of bamboos
 Properties of bamboos
 Comparison between steel and bamboos
 Bamboo and other construction materials
 Selection and preparation of bamboos
 Construction principles
 Roofing with bamboos
 Advantages of bamboo as structural member
 Disadvantages of bamboo as structural member
 Conclusion
 References
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3.  The present presentation deals with cost-wise comparison of steel
reinforcement with bamboo reinforcement. The utilization of bamboo
reinforcement as replacement of steel reinforcement is gaining immense
importance today, mainly on account of the improvement in the economical aspect
combined with ecological benefits.
 Recently, in the attention in response to global warming issues and
sustainable society, the manufacturing using natural materials has become actively.
Bamboo, low cost, fast growing, and broad distribution of growth, is expected to
contribute significantly to earthquake-resistant construction and seismic retrofit
technology in the developing countries
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4.  In recent years, steel prices have soared. For developing countries, steel is
difficult to obtain because of expensive prices, and for the construction industry,
usage of steel is currently limited heavily. The production of steel has high
consumption of fossil fuels, so, the steel discharge in the construction of structures
has been presented, showing the possibility of drastic reduction by research
institutes.
 Meanwhile, for developing countries, it is important to make the development of
buildings construction; low cost, no requirement of sophisticated technologies and
reliable construction methods.
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5. Bamboos belong to the grass family Poaceae (Gramineae). In India, there are 125
indigenous as well as exotic species of bamboos belonging to 23 genera. Bamboo
forests occupy an area of 10.03 million ha, roughly 12.8% of the total forest area in
the country.
Bamboos are some of the fastest-growing plants in the world, due to a
unique rhizome-dependent system. Certain species of bamboo can grow 35
inches/890 mm within a 24-hour period, at a rate of 0.00003 km/h (a growth of
approximately 1 mm (or 0.02 inches) every 2 minutes).
3.1 Historical use of bamboos.
Around 16th – 17th Centuries BC this time, bamboo was being used to manufacture
bows, arrows and other hunting materials as the wood is plentiful and extremely
durable. Of course, bamboo was also being used to create household items and even
the structure of the house itself.
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6.  The geographical distribution of bamboos is governed largely by the conditions of
rainfall, temperature, altitude and soil. Most of the bamboos require a temperature from
8 degree c to 36 degree c, a minimum annual rainfall of 1000 mm and high atmospheric
humidity for good growth.
 Following are the some of the certain species across the world

 table 1.0(distribution of bamboo)
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Genus Number of Species Distribution
Bambusa c37
Tropical and subtropical Asia,
especially in monsoon and wet
tropics; mostly cultivated
cephalostachyum 11
From north eastern Himalayas to
Thailand and Mindoro; mountain
to lowland forest
Dendrocalamus c.29
From Indian subcontinent
throughout South-East Asia; dry
and humid tropics
Dinochloa c.20
Malesia; hill and lowland
dipterocarp forest
Gigantochloa c.24
South-East Asia, wild or
cultivated; humid tropics

7.  Some specific properties of Bamboo(bambusa and dendrocalamus) are as given
below:
 Specific gravity - 0.575 to 0.655
 Average weight - 0.625 kg/m
 Modulus of rupture - 610 to 1600 kg/cm2
 Modulus of Elasticity - 1.5 to 2.0 x105 kg/cm2
 Ultimate compressive stress- 794 to 864 kg/cm2
 Safe working stress in compression – 105 kg/cm2
 Safe working stress in tension - 160 to 350 kg/cm2
 Safe working stress in shear- 115 to 180 kg/cm2
 Bond stress - 5.6kg/cm2
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8. Properties Steel (FE500 as per IS1786-2008) Bamboos
Yield strength 379.02 N/MM2 180.6 N/MM2
Ultimate tensile strength 500.23 N/MM2 220.88 N/MM2
Elongation in % 20 15.07
CARBON EMISSION (for 3m
length to support 300kg load)
15 to 17 0 to 0.1
mass per 3 meter length 10kg 6.5kg
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9. properties Red brick Acc sheets Bamboos Steel
Density 1920 kg/m3 0.3 to 0.4 7750 to 8050 kg/m3
Thermal conductivity 0.6 0.04 to 0.12 50.2
Carbon emission 1.3 0 to 0.1 15 to 17
Composition
By weight
Silica(sand),-50%
Alumina(clay)-20%
Lime-2 to 5%
Natural
Grade
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10. 8.1 selection…
 The following factors should be considered in the selection of bamboo culms (whole plants) for use as
reinforcement in concrete structures:
 Use only bamboo showing a pronounced brown colour. This will insure that the plant is at least three
years old.
 Select the longest large diameter culms available.
 Do not use whole culms of green, unseasoned bamboo.
 Avoid bamboo cut in spring or early summer. These culms are generally weaker due to increased fibre
moisture content.
 The culms should be well seasoned before use so that sweetness of the bamboo will be lost and insect
attacks will be minimised which is used for construction
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11.  8.2.1 sizing….
 Splints are generally more desirable than whole culms as reinforcement. Larger culms should be split
into splints approximately 3/4 inch wide. Whole culms less than 3/4 inch in diameter can be used
without splitting
 Splitting the bamboo can he done by separating the base with a sharp knife and then pulling a dulled
blade through the stem. The dull blade will force the stem to split open; this is more desirable than
cutting the bamboo since splitting will result in continuous fibres and a nearly straight section
 8.2.2 seasoning...
 When possible, the bamboo should be cut and allowed to dry and season for three to four weeks before
using. The culms must be supported at regular spacing to reduce warping.
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12.  8.2.3 waterproof coatings….
 When seasoned bamboo, either split or whole, is used as reinforcement, it should receive a waterproof
coating to reduce swelling when in contact with concrete. Without some type of coating, bamboo will
swell before the concrete has developed sufficient strength to prevent cracking and the member may be
damaged, especially if more than 4 percent bamboo is used. The type of coating will depend on the
materials available.
 A brush coat or dip coat of asphalt emulsion is preferable. Native latex, coal tar, paint, dilute varnish,
and water-glass (sodium silicate) are other suitable coatings.
 In any case, only a thin coating should be applied; a thick coating will lubricate the surface and weaken
the bond with the concrete.
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13.  In general, techniques used in conventional reinforced concrete construction need not the changed when
bamboo is to be used for reinforcement.
 9.1 concrete mix proportion…
 The same mix designs can be used as would normally be used with steel reinforced concrete. Concrete
slump should be as low as workability will allow. Excess water causes swelling of the bamboo.
 High early-strength cement is preferred to minimize cracks caused by swelling of bamboo when
seasoned bamboo cannot be waterproofed.
 9.2 placement of bamboos…
 Bamboo reinforcement should not be placed less than 1-1/2 inches from the face of the concrete surface.
When using whole culms, the top and bottom of the stems should be alternated in every row and the
nodes or collars, should be staggered. This will insure a fairly uniform cross section of the bamboo
throughout the length of the member, and the wedging effect obtained at the nodes will materially
increase the bond between concrete and bamboo.
 clear spacing between bamboo rods or splints should not be less than the maximum size aggregate plus
1/4 inch. Reinforcement should be evenly spaced and lashed together on short sticks placed at right
angles to the main reinforcement. When more than one layer is required, the layers should also be tied
together. Ties should preferably be made with wire in important members. For secondary members, ties
can be made with vegetation strips.
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14. Bamboo must be securely tied down before placing the concrete. It should be fixed at
regular intervals of 3 to 4 feet to prevent it from floating up in the concrete during
placement and vibration.
In flexural members continuous, one-half to two-thirds of the bottom longitudinal
reinforcement should be bent up near the supports. This is especially recommended in
members continuous over several supports.
Additional diagonal tension reinforcement in the form of stirrups must be used near
the supports. The vertical stirrups can be made from wire or packing case straps when
available; they can also be improvised from split sections of bamboo bent into U-shape,
and tied securely to both bottom longitudinal reinforcement and bent-up
reinforcement. Spacing of the stirrups should not exceed 6 inches.
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15.  Bamboo is one of the best roofing materials and provides ample sturdiness to the
structure.
 It is a proven shield against forces of nature or animals and are considerably light
weighted which makes them easy to install.
 The bamboo roofs encompass purlins, rafters and trusses.
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16.  10.1.1 Traditional Bamboo truss.
 In the past bamboo truss was made by putting the bamboo poles together and strapping a rope around
them.
 He issue with this type of bamboo truss connectors is that the load of the roof was not equally
distributed. There is friction which may compromise the strength of the roof.
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17. 
 New joiners and connectors have been designed in recent times. Thanks to
advancement in technology, skilled engineers and architects.
 These joiners and connectors can be made in various shapes and sizes. This depends
on the number of poles to be connected and the design of the roof.
 With the modern joiners there is rarely any friction between the poles. The weight is
equally distributed. Incorporation of little steel helps in overcoming the problems
faced in traditional system.
 The steel joiners do not need a lot of investment and hence the cost of the
entire Bamboo structure is low.
 The amount of skilled labour required is also low. This means even in the rural areas
these structures can be built using modern joiners.
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18.  Another way of covering the roof with bamboo is to cut open the bamboo exactly in
half. The nodes within he bamboo clum are removed and cut into adequate sizes.
 The bamboo halves are then placed in an interlocking manner. One have faced the
ground and the other faces the sky. The half facing the ground is holding 2 halves
facing the sky.
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19.  It has almost zero carbon emission.
 Some of the species of bamboo has more tensile strength than steel.
 Due to its high elasticity nature, structures made with bamboos are more capable of
withstand against earthquake.
 It does not requires sophisticated tools or equipment for its cutting.
 In each of its nodes, bamboo has a dividing and transverse wall that maintains strength
and allows bending, thus preventing rupturing when bent.
 Easily available across the world.
 It is lighter material thus it can be use in substitution of other same property heavier
materials.
 It has very low thermal conductivity.
 Resistance of electricity.
 No skilled labour is required for cutting and construction.
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20.  Water absorption is very high, the bamboo used as a reinforcement absorb water from
concrete mixture thus it reduces the strength of concrete as well as its tensile strength.
 It requires waterproofing agent before its placement.
 Since bamboo is a natural material, every bamboo has not same tensile and compressive
strength. Thus we have to check the properties of every bamboo each time before placing
 Most important it is a brittle material hence it will not give any warning before its failure.
 Due to smooth surface of bamboo the bond between concrete and bamboo will be very
less.
 It is not fire resistance.
 Every bamboo has irregular shape even a single bamboo differs its dimensions after one
or more nodes.
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21.  As per above study we can conclude that bamboo has similar characteristics as steel
but it has major faults too like waterproofing, brittle nature, low bonding with concrete,
requires more maintenance than steel. It cannot be recommended for reinforcement in
sky scrapers, important buildings, dams, and other certain construction.
 On the other hand, bamboo has very low carbon emission and low thermal
conductivity as compare to other building materials which cannot be ignorable thus
bamboo can be used in low rise buildings such as G+1 and G+2 and where the steel is
not available.
 Thus, In the green building concept use of bamboo reinforced concrete may be
recommendable.
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22.  Anurag Nayak, Arehant S Bajaj, Abhishek Jain, Apoorv Khandelwal, Hirdesh Tiwari, aug(2013),
“Replacement of Steel by Bamboo Reinforcement’’
 Harish Sakaray, N.V. Vamsi Krishna Togati and I.V. Ramana Reddy feb (2012), “Investigation on
properties of bamboo as reinforcing material in concrete’’
 Francis E. Brink and Paul J. Rush, feb(1996), “Bamboo reinforced concrete construction’’
 Bhalla , S., Janssen J.A.J “ Design Bamboo As Green Alterative To Concrete And Steel For Moder
Structures.”
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23. THANK YOU
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