考虑地震影响的小间距隧道围岩流变损伤

针对隧道围岩的流变特性，基于拟静力法建立了隧道围岩在流变过程中有地震作用时的长期变形与稳定性分析格式，并对三车道小间距隧道的开挖施工过程进行了粘弹塑性数值分析，探讨了地震对小间距隧道围岩与支护结构的影响。数值仿真对比分析表明：地震因素对隧道周边各点的水平位移影响较大，对竖向位移影响较小；中间岩壁在地震影响下，可能发生错动破坏，而且在施工方法的共同影响下有侧向移动的趋势，这将对小间距隧道的安全稳定产生不利的影响。给出了在典型施工方式下，三车道隧道围岩破坏特征及其施工过程中小间距隧道洞周特殊点粘弹塑性的变形规律，可作为小间距隧道设计参考。

Rheologic Damage and Earthquake Influence on Surrounding Rock of Small Spacing Tunnels

Based on quasi-static method, considering the earthquake action in rheological process of surrounding rock for small spacing tunnels, the formulas for analyzing the long-term deformation and stability are set up. The visco-elasto-plastic numerical simulation is studied in consideration of the excavating construction, and the influence of earthquakes on the surrounding rock and supports is researched for three roadway tunnels with small spacing. It is shown by the comparison of simulating results that the earthquake factors have larger influence on horizontal displacements than on vertical ones at all points on tunnel boundary. The shear damage and lateral movement of the rock interval between two tunnels may take place due to earthquakes and construction, which have an unfavorable effect on the safe and the stability of tunnels with small spacing. The damage characteristic of surrounding rock and the visco-elasto-plastic deformation law at particular points are given under the condition of typical construction way for three driveway tunnels. Those have a reference meaning for tunnel engineering design. 2 tabs, 9 figs, 8 refs.