Bending properties and design strength of reconstituted bamboo at different temperatures

Abstract

AbstractReconstituted bamboo is a unidirectional fiber adhesive material with strong temperature sensitivity. The bending strength and deformation of reconstituted bamboo beams at different temperatures were measured using a three‐point bending test. At 10°C, 30°C, and 50°C, the samples showed a brittle tensile fracture, simple tensile fracture, and splintering tensile fracture modes respectively, the bending failure pattern of reconstituted bamboo was intensified with increasing temperature. The results show that with increasing temperature, the degree of interlaminar debonding cracking and longitudinal tensile fracture is aggravated, accompanied by shearing. The ultimate bearing capacity of the reconstituted bamboo decreased from 182.25 MPa to 124.89 MPa (a reduction of 31.47%) and the flexural modulus decreased from 11,329.25 MPa to 8679.90 MPa (a reduction of 23.39%) as the temperature increased from 10°C to 50°C. The temperature has little effect on the initial stiffness, and the postelastic stiffness decreases significantly (by 53.01%) with increasing temperature. The thermal softening effect has a significant influence on the plastic behavior of bamboo. A model of the design value of bending strength considering the temperature was established, and the design value of bending strength was evaluated.