预应力锚索桩板墙减震锚头弹簧刚度系数研究

以某高原铁路高烈度地震区路堑段为背景，采用有限元方法建立锚头设置弹簧组件的减震锚拉桩板墙分析模型，研究锚索体系刚度对桩板墙地震响应特征的影响规律，探讨锚头弹簧刚度的优化参数范围。结果表明:设置减震锚头的桩板墙锚索受力较普通锚拉式桩板墙结构有明显改善，地震作用下锚索拉力峰值、震荡幅值及残余拉力随锚索体系刚度降低近似呈线性减小规律，但锚索对桩身的约束作用减弱，桩顶动位移峰值及残余位移呈反“S”形增大。为了协调和统一地震作用下降低锚索拉力和桩顶位移的抗震需求，应根据桩顶水平位移的极限对锚头的弹簧刚度进行优化。

Research on Spring Stiffness Coefficient of Shock-absorbing Anchor Head of Prestressed Anchor Cable Pile-slab Wall

Taking the cutting section of a plateau railway with high seismic intensity as the background, the finite element method has been used to establish the analysis model of shock absorption anchor-drawn pile slab wall with anchor head and spring assembly so as to study the influence law of anchor cable system stiffness on seismic response characteristics of pile slab wall, and the optimization parameter range of anchor head spring stiffness. The result shows: The force of the anchor cable of the pile-slab wall with spring component anchor head is significantly improved compared to the ordinary anchor-pile-slab wall structure. The peak value, vibration amplitude and residual tension of the anchor cable under the action of seismic action are approximately linearly reduced with the stiffness of the anchor cable system. However, the restraint effect of the anchor cable on the pile body is weakened, and the peak dynamic displacement and residual displacement of the pile top increase in an inverse "S" shape. In order to harmonize and unify the seismic demand of reducing anchor cable tension and pile top displacement under seismic action, the spring stiffness of anchor head should be optimized based on the limit of pile top horizontal displacement.