Research on tensile and compressive representative volume-element model and failure mechanism of bamboo scrimber

The macroscopic mechanical properties of bamboo scrimber can be better elucidated by investigating its failure mechanism at the micromechanical scale. To this end, tension and compression tests were conducted in this study on the bamboo scrimber in parallel-to-grain. By employing micromechanics theory, a Representative Volume Element (RVE) model of the bamboo scrimber was established to offer insights into the micromechanical failure mechanism of the bamboo scrimber. The research results indicated that the stress-strain curves of tensile and compressive specimens exhibited contrasting characteristics with linear curves observed in tensile tests and nonlinear ones featuring prominent elastic-plastic deformation in compression tests. Notably, the RVE model with a linear vascular bundle accurately simulated the tensile behavior but fell short of capturing the compression behavior of specimens. Therefore, an RVE model with a nonlinear vascular bundle should be employed for compressive specimens. Moreover, the failure mechanisms of the tensile and compressive specimens differed. The failure mechanism of tensile specimens involved the initial degradation of the weak overlapping parts of the vascular bundle. In contrast, the compressive specimens exhibited a failure mechanism characterized by the initial deterioration of the bonding interface, leading to a gradual reduction in load bearing by the vascular bundles until the specimens collapsed locally.