Bamboocrete construction

KEYWORDS:

Special properties	Cheaper than other equally strong structures
Economical aspects	Low to medium costs
Stability	Good
Skills required	Bamboo and masonry construction skills
Equipment required	Carpentry and masonry tools
Resistance to earthquake	Good
Resistance to hurricane	Good
Resistance to rain	Good
Resistance to insects	Low
Climatic suitability	All except very hot dry climates
Stage of experience	Experimental

SHORT DESCRIPTION:

• The bamboocrete house shown overleaf was implemented in 1976 by Dr. U.C. Kalita, et al (Bibl. 24. 11), Regional Research Laboratory, Jorhat (Assam), India.

• On a concrete foundation with burnt brick base course and flooring, a framework of secondary species timber provides the structural support for infill panels and curved roofing elements made of split bamboo lattice-work, plastered with cement mortar.

• The use of bamboo to substitute steel reinforcement in concrete is of considerable economic interest, as steel is expensive and often imported. However, bamboo shrinks on drying - over 4 times more than the concrete - so that there is no bond between the bamboo and concrete. Furthermore, the alkalinity of concrete gradually destroys the bamboo fibre, which finally loses all its strength.

• Recent research (Bibl.24.10) has shown some possible remedies: 1.Coating the bamboo with hot bitumen and improving bonding by covering it with coarse sand, driving in 25 mm nails or tying coconut fibre ropes around the bamboo (developed by D. Krishnamurthy); 2. Using only the outer section of bamboo (because of its higher tensile strength and elasticity) and twisting bundles of three split-bamboo strips around each other (developed by 0. Hidalgo Lopez).

• Further research is necessary, especially with a view to fibre deterioration.