Responses of partially-encased composite structural members subjected to lateral impact load: Experimental and analytical study

The lateral impact responses of partially-encased composite (PEC) members were investigated via both experimental and analytical approaches. The impact experiments were conducted on PEC members to obtain their deformation process, failure mode, impact force–time and displacement–time responses. The effects of the initial velocity, clear span, impact direction and types of transverse reinforcements (i.e., links and stirrup) on impact responses of PEC members were experimentally investigated. The results indicated that the higher impact velocity would result in higher impact force, larger specimen deformation and energy dissipation. The PEC member with larger span exhibited smaller impact resistance, inducing larger specimen deformation. The impact direction had significant influence on the impact response of PEC members due to the differences in bending resistance. While the types of the transverse reinforcements employed in this study had negligible effect on the impact behaviours. Moreover, a two degrees-of-freedom (2-DOFs) model was developed to calculate the responses of the PEC members under the lateral impact. The developed 2-DOFs model demonstrated its applicability by accurately predicting the test results.