Behaviour under Bending Loads of Workable Bamboo Bio-Concrete

This work presents the results obtained in an experimental program that evaluated the flexural behavior of workable bio-concretes of bamboo. Leftovers and fragments were reduced to particles using an industrial grinder and a knife mill. The resulting material was used in its entirety, including the fines passed through the 1.18 mm sieve. The cement: bamboo ratios used were 1: 3.0 and 1: 2.5 corresponding to a bio-aggregates volume of 45 and 50%, respectively. The water to cement (W/C) ratios studied were 0.40 and 0.50. The use of fines bio-aggregates and viscosity modifying agent (VMA) helped to control the exudation and segregation of the fresh bio-concretes which presented spreading of 290 mm +/- 20mm. The modulus of rupture (MOR) at 28 days varied from 1.26 to 1.85 MPa while the modulus of elasticity (MOE) varied from 1.42 to 2.76 GPa. There was significant influence of particle volume and W/C ratio on the hardened properties of the bio-concretes. There was a post-fissuration behavior with gradual reduction of load and increase of deformation, demonstrating the benefit of the particles as reinforcement element and control of cracking.