TURNKEY PROJECTS

BAMBOO CONSTRUCTIONTUSHAR CHOUDHARI ANKITA KOLAMKAR6th batch - PGP-ACM

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INTRODUCTIONBamboo has been in wide usage since ancient times as a low-cost material for houses, bridges etc.Recently started appearing in designer homes as flooring, walling and paneling materialIs viewed as a material preferred only by the poor or for temporary constructionsUnpopular in conventional construction due to low durability, lack of structural design data, exclusion from building codes etc.

Facts about bambooBamboo is a perennial grass and not a tree as is commonly perceived.1450 species are found in diverse climates across the world, however, not all of these are suitable for construction.One of the fastest growing plants on Earth. Its growth rate ranges from 30cm to 1 m in 24 hours.The strongest part of a bamboo stalk is its node, where branching occurs.Bamboo has also long been used as scaffolding; the practice has been banned in China for buildings over 6 storeys but is still in continuous use for skyscrapers in Hong Kong.

advantagesStrength - Bamboo is an extremelystrongnatural fibre, on par with standard hardwoods, when cultivated, harvested, prepared and stored properly.Flexibility - Bamboo is highly flexible.During its growth, it may be trained to grow in unconventional shapes. After harvest, it may be bent and utilized in archways and other curved areas. Earthquake-resistance - It has a great capacity for shock absorption, which makes it particularly useful in earthquake-prone areas.

advantagesLightweight - Bamboo is extremelylightweight. Consequently, building with bamboo can be accomplished faster with simple tools than building with other materials. Cranes and other heavy machinery are rarely required.Cost-effective Economical, especially in areas where it is cultivated and is readily available. Transporting cost is also much lesser.Durability - Aslong-lastingas its wooden correlates, when properly harvested and maintained.

How to protect bambooUNTREATED BAMBOOUntreated bamboo has the following life spans in different conditions> Exposure to soil and atmosphere = 1-3 years> Under cover = 4-7 years> Very favourable conditions = 10-15 yearsNatural durability also depends on the species of the bambooPRE-HARVEST AND POST HARVEST PRECAUTIONSFelling during low sugar content season i.e. dry seasonFelling of mature bambooPost harvesting transpirationWater soaking

How to protect bambooBORAX BORIC ACID PRESERVATION TREATMENTDepending on the diameter of the bamboo, different sized drill bits, attached to a long steel rod, are used to drill into the centre of thebamboo culmsthroughout their whole length.

At the preservation treatment pool, bamboo soaks in borax-boric acid solution (1:1.4)for 2 days to allow the mineral to penetrate all the nodes and diaphragms.

Bamboo is removed and stacked vertically so the solution can drain and be reused.

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How to protect bambooPreservative solution is recharged after four cycles by adding water and the chemicals. Preservation treatment costs a minimum charge of INR 4.50 per pole.BORAX BORIC ACID PRESERVATION TREATMENT

Next, thebamboo polesare left to bask in the sun depending on the amount of sunlight

The bamboo poles are left to dry slowly in a cool, dry place until they are used for construction.

How to protect bamboo

During the casting and curing of concrete, reinforcing bamboo absorbs water and expands

The swelling of bamboo pushes the concrete away

Then at the end of the curing period, the bamboo loses the moisture and shrinks back almost to its original dimensions leaving voids around itself The swelling and shrinkage of bamboo in concrete create a serious limitation in the use of bamboo as a substitute for steel in concrete.

One effective treatment is the application of a thin layer of epoxy to the bamboo surface followed by a coating of fine sand.

How to protect bambooSHRINKAGE REDUCTIONNEEM SEED OIL TREATMENT

Oil obtained from neem seeds can be used to improve water resistance and dimensional stability of bamboo culms particularly at high oil-treatment temperature.

Bamboo samples soaked in hot neem seed oil at 60C for 4 hours had better water resistance and dimensional stability than samples soaked in oil at room temperature for 24 hours.

Bamboo foundationsCOMPOSITE BAMBOO-CONCRETE FOUNDATIONS

Single Post FootingStrip Footing

Bamboo foundationsBAMBOO PILES

Bamboo compacts soft soil, thus increasing the bearing capacity of soil.

The friction provided by the construction-grade bamboo increases its load-bearing capacity.

Treated split bamboo piles 8m long and 80 to 90mm in diameter were filled with coconut coir strands wrapped with jute.

A sustainable house in Thiruvananthapuram, Kerala where bamboo piles have been used as foundation . The foundation is further strengthened by bamboo reinforced concrete.

Bamboo foundationsBAMBOO PILES

The sections were then tied with galvanised iron wire. After installation of the piles @2m c/c by drop hammer, the area is covered with a 2.5m surcharge of sandy material.

Bamboo WALLS

WOVEN BAMBOO WALLVERTICAL HALVED CULMSBAJAREQUEWHOLE BAMBOO CULMSWATTLE AND DAUB

RESISTANCE TO EARTHQUAKES High residual strength to absorb shocks and impacts. Flexure coupled with its very low mass.

Prototype house built with bamboo sheet roofing and bamboo-reinforced concrete walls withstood a simulated earthquake measuring 7.8 on the Richter scale

A bamboo house in Bhutan that withstood an earthquake that occurred at Sikkim (epicenter) measuring 6.9 in September 2011

30 houses at the epicenter of a 7.6 magnitude earthquake survived without any damage in Costa Rica in 1991

MECHANICAL PROPERTIES PropertyValueDensity0.5 0.9 gm/ccCompressive Strength53 100 MPaTensile Strength111 219 MPaBending Strength86 229 MPaBending Elasticity6882 20890 MPa

bamboo column AND BEAM

Bamboo Reinforced ColumnBamboo Beams

Comparative analysis

Comparative analysis

Comparative analysis

Limitations and drawbacksFew considerations currently limit the use of bamboo as a universally applicable construction materialJointing techniques - Although many traditional joint types exist, their structural efficiency is low. Considerable research has been directed at the development of more effective methods.Flammability - Bamboo structures are not fire-resistant, and the cost of treatment, where available, is relatively high.Lack of design guidance and codification - The engineering design of bamboo structures has not yet been fully addressed. There is little or no data containing specifications of bamboo.