Monotonic and cyclic load of pine wood under uniaxial compression: experiments and modeling

Abstract

To analyze the behavior of wood under uniaxial monotonic deformation, we applied an analytical model to separately control of the pre-peak and post-peak branches of the load-displacement curve. Two criteria for the transition of wood into the plastic stage of deformation are considered. To analyze the behavior of wood under cyclic uniaxial deformation, we used the load-displacement curve obtained for monotonic deformation as an envelope. Equations for the plotted of load-displacement curves under cyclic loading with incomplete unloading are proposed. As an experimental and model illustration, the behavior of a pine specimen under cyclic uniaxial compression with incomplete unloading in the range from 8 to 15 kN is considered. Because the highest cyclic load exceeds the load at the point of transition of wood into the plastic stage, the deformation process has already after 54 cycles moved to the downward branch of the load-displacement curve for monotonic deformation. The simulation results are in agreement with experimental and literature data, which suggests the suitability of this method for the study of some wood-based composites.