层间孔隙岩溶影响隧洞稳定性的数值模拟研究

以重庆巴南区某引水工程为研究背景,采用基于流固耦合理论的二维有限元数值模拟方法,通过有限元软件ABAQUS对隧洞工程选取13个主要断面建立相应的数值模拟模型,分析不同位置水工隧洞断面的围岩在开挖过程中的应力、位移和涌水量变化情况,得出层间孔隙岩溶对隧洞开挖稳定性的影响并提出建议。研究结果表明:隧洞跨层时应力及位移均会产生复杂变化;透水层的存在一定程度上加快了应力消散,并减弱隧洞变形速度;隧洞涌水量与其在透水层中的面积大小有关。

Numerical Simulation on Effects of Interlayer Pore Karst on Tunnel Stability

Based on a water diversion project in Banan District of Chongqing,this paper established corresponding numerical simulation models of 13 main sections in tunnel engineering through the finite element software ABAQUS,by using the two dimensional finite element numerical simulation method based on fluid structure coupling theory.By analyzing the stress,displacement and water flow of surrounding rock during excavation when the hydraulic tunnel is in different positions,this paper obtains the influence of the interlayer pore Karst water on the stability of the tunnel in excavation process and makes suggestions.The results show that:the stress and displacement of surrounding rock changes complexly when the tunnel crosses layers;the existence of the permeable layeraccelerates the stress dissipation in a certain extent and weakens the tunnel deformation speed;the water inflow of tunnel is relating to its area size in the permeable layer.