Bamboo – A Green Construction Material for Housing towards Sustainable Economic Growth
Introduction:
India has a rich diversity of bamboo and they belong to family Poaceae, sub family bambusoideae which comprises both lignified and herbaceous bamboos and bamboo allies. In India there are 115 species which are from Indian sub-continent whereas 63 species are under 13 genera from present day India and among others 115 species under 20 genera. The North Eastern region of India has more or less than 50% of total bamboo species available in India. There is boom in construction and civil engineering activities due to rapid improvements in procurement of building materials. This has posed many challenges due to few unsustainable pollutant and exhaustive materials. It has also significantly created opportunities for innovative and unconventional resources to emerge. Buildings account for nearly 40 % of the total energy consumption globally. Energy efficient technologies could reduce the consumption approximately to 60 %. In India, the building sector accounts for about 35 % of the nation’s total energy consumption and is growing at 8% rate each year. Hence there is a need for energy efficient and economical methods of construction using bamboo as one of the green building material towards sustainable growth.
SIGNIFICANCE OF BAMBOO HOUSING TECHNOLOGY:
Bamboo based housing system has very high potential for mass housing, housing in disaster prone areas and for earthquake resistant structures and other applications like farm houses, resorts, eco- tourism camps etc. The low mass of the bamboo based building is an advantage under earthquake loading as compared to masonry and concrete buildings. The housing technology developed by IPIRTI is different from conventional bamboo construction practices. The method uses round bamboo as column, rafter, purlin and truss as main load bearing element, split bamboo for grid walls plastered with cement. Bamboo Mat Board is used as gusset in combination with mild steel bolts for load bearing joints in roofing structure and Bamboo Mat Corrugated Sheet for roof cladding.
ADVANTAGES OF BAMBOO AS A CONSTRUCTION MATERIAL:
The main advantages of Bamboo as a construction material are :
• It has higher tensile strength than steel because its fibers run axially.
• Bamboo culms have a characteristics physical form which gives them high strength weight ratio.
• Bamboo is very elastic. At every joint (node) in the bamboo, there is a cross partition wall on account of which bamboo at their nodes are very hard and do not bend or break easily.
• Bamboo has high load bearing capacity which may be considered as one of the highly endorsed materials for tall structures.
• It is widely preferred in earthquake prone regions due to its elastic features.
• Bamboo can easily be cut into required size and split up into strips using simple tools and ordinary workers.
• Because of lightweight, structures made of bamboo are safe in earthquake prone areas. In case of collapse, house can be re-erected very quickly at very little cost.
• Bamboos are easily displaced or installed making it very easier for transportation and construction.
• Unlike other building materials like cement and asbestos, bamboo poses no danger to health.
• It absorbs carbon dioxide and releases 35% more oxygen into the atmosphere than an equivalent stand of hardwood trees.
Conclusion:
Resilience coupled with light weight of bamboo makes an ideal building material for housing in disaster and earthquake prone areas. It has the capacity to withstand repetitive loadings and absorb more energy and show larger deflections before collapse and thus it is safer under earth tremors. As the design guidelines were inadequate, the application of bamboo as an engineering material was largely based on practical and engineering experience as an engineering material. . Low cost bamboo houses are cheap and safe alternative to the shelters of plastic, wood and stone that are currently being used by many homeless people.