Bending and shear performance of a cross-laminated composite consisting of flattened bamboo board and Chinese fir lumber

Bamboo-wood composites are effective for utilizing the mechanical properties of bamboo and fast-growing wood resources. Investigation the application of flattened bamboo in engineering structures provides added value to bamboo resources. This paper analyzes the flatwise bending and shear properties of cross-laminated bamboo and timber (CLBT) panels consisting of flattened bamboo boards and Chinese fir lumber. A three-layer cross-laminated timber (CLT) panel made from Chinese fir lumber was used for comparison. The mechanical properties of the CLBT and CLT panels in the major strength direction were obtained through experimental tests, and theoretical and finite element models were developed to predict the panels' bending stiffness and strength. The calculated values were compared with the experimental data. The results showed that the failure modes of the three groups of CLBT panels were similar to those of the CLT panel and were predominantly rolling shear and bonding delamination. The bending strength and modulus of the CLBT were higher than that of the CLT. Increasing the number of layers of the flattened bamboo board improved the maximum bending moment and bending stiffness of the CLBT. The bending stiffness and strength of the CLBT/CLT obtained from the finite element model were in better agreement with the static test values than the theoretical model values. The results of this study provie new information for future engineering applications and the structural design of CLBT.