Elastoplastic performance of wood under compression load considering cross-grain orientation and moisture content

This study explored the feasibility of the finite element method (FEM) and Hankinson formula to predict the compressive properties of cross-grain wood with a wide range of moisture content, avoiding the waste of materials and time in experimental methods. This study examined the influence of moisture content and cross-grain orientation on the elastoplastic performance of beechwood under compressive loads. The comparison of compressive load-displacement curves between the experiment and FEM was achieved, and the relative errors of compressive yield strength or modulus of elasticity between the experiment and FEM. The stress concentration distribution and failure models of different principal planes were analyzed. It demonstrated that the FEM could simulate compressive elastoplastic properties of wood with 45o cross-grain and a broad range of moisture content. For cases of 45o cross-grain orientation, comparisons between the experimental data and FEM, and Hankinson formula, were conducted which validated that the Hankinson formula can predict beechwood's compressive yield strength and elastic modulus with multilevel grain orientations and moisture contents. Regression models were established based on the Hankinson formula to forecast the compressive yield strength or modulus of elasticity for a broad range of moisture content and random grain direction. This study can assist in the rational utilization of cross-grain timber in terms of structural optimization of outdoor wood products.