超大型地下洞室群的三维地震响应分析

3-D seismic response study on large scale underground group caverns

在大型水电站、核电站的地下厂房及大型地铁车站等超大型地下洞室群结构的动力反应分析中 ,围岩的动刚度特性不仅涉及到围岩对结构的动力约束作用 ,而且也是地震动输入机制的关键和地下结构分析中的难点。采用阻尼影响抽取法研究了围岩动刚度的动力特性 ,提出了岩石地下结构抗震分析的实用算法。该算法具有较好的精度和计算效率。在此基础上对溪洛渡超大型地下洞室群的抗震安全性进行了评价。

The 3 D seismic response analysis of underground group caverns for underground plants of large hydropower station or nuclear power station or subway station is difficult because of its dynamic interaction with the surrounding rocks. The dynamic characteristics of surrounding rocks are not only concerned with their constraint on underground structure, but also related to the earthquake input in the dynamic interaction analysis. In this paper, the dynamic impedance is studied using so called damping solvent extraction method,and a practical approach with better accuracy and lower computational cost is proposed for large underground caverns in rock.Then the anti seismic safety of Xi luo du large scale underground caves is evaluated and possible seismic countermeasures are suggested.