金川矿区深部巷道围岩流固耦合稳定性数值模拟

 地下水渗流会影响巷道围岩力学性质，本文结合流固耦合基本原理，以金川二矿区深部巷道为例，采用MIDAS/GTS建立了金川二矿区1000m水平某巷道流固耦合模型，研究渗流对围岩应力场、围岩变形及开挖卸载影响。计算结果表明，渗流作用对巷道围岩竖向应力的影响大于水平应力，渗流也导致围岩最大、最小主应力比无水时偏大。渗流和无水状态下围岩变形空间分布具有相似性，渗流对巷道围岩水平位移影响相对较小，但对围岩竖向位移影响较大，其中巷道拱部竖向位移明显大于无水状态，渗流时拱部最大位移约为8.2mm，而无水时仅2.3mm左右。因此，渗流效应将导致巷道顶板稳定性变差。开挖卸载对渗流场的影响表明，开挖后巷道周边压力水头迅速降低，孔隙水压力最小降为零，且孔隙水压力也从水平层状分布变为沿巷道轮廓环形带状分布。

Numerical Simulation of Fluid-Structure Interaction Stability for Jinchuan Deep Roadway

Groundwater flow would affect the mechanical properties of surrounding rock. In this paper, based on the fluid-solid coupling basic principles, and taking the Jinchuan second mining area deep roadway as an example, a 1000m level roadway fluid-solid coupling computational model is established, then the surrounding rock stress field, the deformation, and the excavation unloading under the seepage condition are simulated. It is shown that the effect of the vertical component of the roadway stress is greater than those of the horizontal components under the seepage condition, the maximum and the minimum principal stresses are larger than those under the anhydrous condition. The rock deformation spatial distributions are similar under the two conditions, the impact of the seepage on the vertical displacement is larger than that on the horizontal displacement. For example, the roadway arch vertical displacement is significantly greater than that under the anhydrous condition, the arch maximum displacement is approximately 8.2mm under the seepage condition, while that under the anhydrous condition is only about 2.3mm, therefore, the seepage effect will lead to the deterioration of the roadway roof stability. The excavation unloading effect on the seepage field is evident that the roadway surrounding pressure head decreases rapidly after the excavation, the minimum pore water pressure drops to zero, and the pore water pressure changes from a horizontally layered distribution to a zonal distribution along the roadway profile.