充水溶洞对隧道围岩稳定性影响的数值模拟

为探讨充水溶洞中水压对隧道围岩稳定性的影响,利用岩石破坏过程渗流-应力-损伤耦合分析软件F-RFPA~(2D),对隧道底部含充水溶洞的围岩破坏过程进行数值模拟研究,并与岩体中存在裂隙时隧道围岩的破坏过程作对比。结果表明,水压的增加使溶洞与隧道间的岩体逐渐产生裂纹,并不断延伸,最终使隧道与充水溶洞贯通;岩体中裂隙的存在改变了裂纹的扩展方向,加速了隧道底部围岩的破坏进程;实际工程中应将隧道底部围岩垂直方向上的位移变化作为事故发生的前兆,制定相应的预防措施,避免事故的发生。

Numerical Simulation on the Influences of Water Filling Cave on the Stability of Tunnel Surrounding Rock

To explore the water pressure effects on the stability of surrounding rocks in water filling cave ,software RFPA2D-Flow (Two-dimensional Real Failure Process Analysis ) is applied to conduct numerical studies on the surrounding rock failure of water filling caves under the bottom of the tunnel and also it is compared with that on surrounding rocks from tunnel of only fracture existed in rock mass .The results show that ,with the increase of hydraulic pressure ,cracks are gradually produced in the rock mass between cave and tunnel ,extended and expanded ,which finally leads a transfixion from tunnel to water filling cave ,and directions of crack growth can be changed by original fracture exist in rock mass ,which accelerates the failure process of the surrounding rock under the bottom of tunnel .In actual engineering ,if there will be a significant in-crease of amount on displacement change in the vertical direction appear in the surrounding rock under the bottom of tunnel , it should be thought of as a sign of disaster ,and protective measures also should be taken in case of major accidents .