Simulation analysis of dynamic response of CFRP-Concrete-Steel tube combination pile under debris flow block impact load

抄録

In order to improve the stiffness and stability of the debris flow pile forest structure, this paper applies the CFRP-Concrete-Steel tube combination pile, which is used in explosion and blast resistant engineering, to the debris flow barrier project; the dynamic responses of concrete pile (CP), concrete-steel tube pile (CTP) and CFRP-Concrete-Steel tube combination pile (CCP) under the impact of large boulders are simulated by finite element software ABAQUS respectively. The Von Mises stress cloud diagram, equivalent plastic strain cloud, pile acceleration and pile bottom support reaction force time course, block velocity time course and impact force time course of the pile were compared and analyzed under different conditions. The simulation results show that the CCP is not only stiff, but also has more distributed stresses and is less prone to damage due to stress concentration when subjected to impact loading, and has the best overall structural stability after being impacted by the boulder. CP and CCP have plastic strain only at the impact site, and the area damaged by the impact of CCP is the smallest; the pile bodies of the three structures are subject to different degrees of oscillation along the impact direction of the debris flow after the impact of the boulder, and the contact with the boulder occurs once or twice during the whole process; the energy transferred from the boulder to the pile body is mainly consumed by the strain and oscillation of the pile body.