地震作用下浅埋隧道系统锚杆参数优化

Parameter optimization for systematic bolts of shallow tunnel under earthquake action

针对增加衬砌厚度往往对提高结构抗震性能效果甚微的问题,提出了通过合理选取系统锚杆参数来增强隧道抗震性能的思路.在静力分析和动力分析两个阶段探讨了不同工况下锚杆及衬砌的受力状态,研究了结构动力响应特征及最大响应值随锚杆参数的变化规律,并对锚杆参数优化问题进行了分析.结果显示:增设墙脚处锚杆可大幅提高隧道抗震性能,同时,锚杆长度及布置方式对结构受力影响较大.

In view of the fact that the effect of improving seismic performance of tunnel by increasing lining thickness was little, the idea for improving seismic performance of tunnel by reasonable selection of the parameters of systematic bolts was proposed. The mechanical states of tunnel lining and systematic bolts under different conditions were discussed through two analysis stages, namely static analysis stage and dynamic analysis stage. The properties of structural dynamic response and the variation law of maximum response with bolt parameters were analyzed. Furthermore, the optimization problem of bolt parameters was deeply studied. The results indicated that the structural seismic performance could be improved greatly by setting bolts at the foot of the curved wall. Meanwhile, the internal forces of lining were influenced by the bolt length and collocation form to some extent.