基于LS-DYNA的某打桩锤机械冲击系统性能仿真

Performance Simulation of a Pile Hammer Mechanical Impact System Based on LS-DYNA

在打桩作业中,机械冲击系统会产生周期性冲击载荷,每一次冲击均产生较大应力,冲击动力特性的研究显得尤为重要。本研究基于ANSYS LS-DYNA软件,建立了打桩锤冲击系统的有限元模型,研究了不同冲击能量下对砧座应力、桩端位移和冲击力大小的影响;研究结果表明:砧座应力集中于上接触面及其圆角处,最大应力达到360.361MPa,能量传递效率为91.86%;最大冲击力和应力与锤芯速度呈线性关系。本研究结果对冲击系统结构设计优化具有重要的指导意义。

In piling operation,the mechanical impact system generates periodic impact loads,and each impact generates large stresses,and the study of impact dynamic characteristics is particularly important.Based on ANSYS LS-DYNA software,this study establishes a finite element model of the impact system of pile hammer,and analyses the effects on anvil stress,pile end displacement and impact force magnitude under different impact energies;the results show that:the anvil stress is concentrated in the upper contact surface and its rounded corners,and the maximal stress reaches 360.361 MPa,and the energy transfer efficiency is 91.86%.The maximum impact force and stress are linearly related to the hammer core speed.The results of this study have important guiding significance for optimising the design of mechanical impact system.