Determination of physical properties of bamboo

Bamboo occupies a prominent place in everyday life and is extensively used for both structural and non-structural purposes. Being a material that compares favourably with timber in strength, bamboo is increasingly being used in many structural applications like posts, pole fencing, scaffoldings, house building, etc. Bamboo has been used worldwide in various construction works as alternative to steel and wood as bamboo is more fibrous and has more tensile strength than steel. Possibilities of construction of boats with bamboo using traditional knowledge enriched with advanced techniques could be visualized and eventually local Bholuka Bamboo (BambusaBalcooa) of Assam was found to be very useful for construction of the boat hull using the lower thick stem of the whole Bholuka Bamboo.

The work investigates the determination of compressive strength, flexural strength, buoyancy force, energy consumed during impact force and tensile strength of the locally grown Bholuka Bamboo. Lime water treated bamboo stems are shaped roughly into square logs by cutting arcs from two sides. Both circular and square section stems of lengths ranging from 120mm to 170mm are compressed in Universal Testing Machine. The maximum compressive load and the ultimate compressive strength for two circular sections were found to be 212kN and 29.93N/mm2 and 291.15kN and 36.71kN/mm2respectively and those for the square sections are found to be 239.85kN and 40.064N/mm2and 166.5kN and 26.48N/mm2 respectively. It is found that the load carrying capacity of this specimen is 66.39%, 75.36% and 75.57% more than Nigerian Bamboo, DendrocalmusStrictus of India and Bangladeshi Bamboo respectively. The direct bending strength test gives an Ultimate Breaking Load and Ultimate stress as 13.10kN and 4MPa and 15.85kN and 5MPa for the circular and square cross sections respectively. The flex test for I-section beams of the bamboo yields a Modulus of Elasticity of 3762.94MPa which is 87.5% less than Charotar bamboo and 57.9% less than Moso bamboo. In tensile test, the maximum breaking load is 28.012kN.The Charpy test conducted on specimens of the bamboo having U cross section consumes an average energy of 12.66kJ which is 1/32thtimes to that of ferrite/martensite laminated steels. Buoyancy test conducted on Bholuka Bamboo yields buoyancy force greater than Gravity force by 27% and 33.33% more than the Bamboos of Thailand.