Combinatorial design and flexural behavior of laminated bamboo–timber​ composite beams

Abstract

The use of bio-based building materials can reduce the pressure on the environment. As bio-based materials, timber and bamboo can be combined to produce excellent building materials. In order to improve the flexural performance of timber beam, a new type of laminated bamboo–timber composite beam was proposed by introducing the material of bamboo scrimber, which has better mechanical properties. The flexural behavior of seven-layer composite beams composed of bamboo scrimber and Douglas fir were tested. Four-point bending tests and theoretical derivations were conducted to study the failure modes, load–displacement curves, and flexural performance of the composite beams and to establish a theoretical model to describe the flexural performance of the composite beams. The results showed that the composite beams exhibited three failure modes. The deformation capacity and stiffness of the bamboo–timber composite beams were improved. Compared with timber beams of the same size, the flexural stiffness and capacity of the composite beams were significantly increased by 33.7% and 31.9%, respectively. Finally, the theoretical calculation proposed to describe the flexural stiffness and capacity could accurately predict the experimental results.