滑坡地段浅埋隧道极限位移研究及围岩稳定性评价

摘要

By establishing the finite element model and detailing the stress releasing rate after the tunnel excavation, the mutation point of the plastic strain is got and the limit displacement of surrounding rock is obtained to prevent the landslide sliding and surface subsidence caused by the improper method in the tunnel excavation. Compared with the displacement of actual supporting conditions and the measured displacement, the limit displacement obtained from the numerical simulation method can satisfy the engineering requirement, can be used as the standard to assess the tunnel stability and can provide the reference for the design of reserved deformation.%通过建立有限元模型，细化隧道开挖后的应力释放率，得到塑性应变突变点，进一步得到在滑坡地段修筑浅埋隧道，围岩变形的极限位移，防止因隧道开挖方法不当引起滑坡滑动、地表沉陷等诱发灾害.通过与实际支护情况下的位移、实测位移进行对比，说明采用数值模拟的方法得到的极限位移能够满足工程要求，作为评定隧道稳定性的标准，为设计预留变形量提供参考依据.