Impact bending behaviors of parallel bamboo strand lumber beams: Velocity sensitivity and anisotropy

Abstract

In order to investigate the impact bending behaviors of parallel bamboo strand lumbers (PBSLs), low-velocity-impact experiments were carried out on six kinds of PBSL beams with fiber orientations varying from 15° to 90° under the condition of impact velocity changing from 2 m/s to 10 m/s. Dynamic anisotropic characterization and velocity effect of the PBSL beam were revealed and quantitatively expressed. PBSL beams have excellent anti-impact ability when the fiber is along the beam axis or the included angle is below 45°. The impact force and the energy absorption increase with the increase of the impact velocity. Failure pattern transforming from tensile failure to shear failure can explain the decrease of the anti-impact ability. In shear failure, increasing impact velocity results in much more energy absorption as the number of fracture zones increases from one to three.