大型地下洞室群变形实测与数值模拟

以某水电站大型地下洞室群开挖为例,建立了三维数值分析模型,研究了洞室群开挖后洞周围岩的变形特性并分析了锚索应力损失对周围岩体变形和应力状态的影响;通过模拟结果与实测结果进行对比,分析模拟方法的合理性和支护方案的可行性.结果表明,围岩水平位移在洞室边墙中部最大,竖向位移在洞室拱顶最大,在洞室交叉部变形也较为显著;模拟结果与实测结果较接近,能良好地反映洞室实际开挖的过程和围岩的变形规律;锚索预应力损失达到某一程度时会使围岩水平位移显著增大.

Deformation Measurement and Numerical Stimulation of Large-Scale Underground Cavern

Abstract： Taking a large-scale underground cavern of hydropower station for example, a 3D numerical model was established to obtain the deformation characteristics of the surrounding rock mass after excavation of the cavern, and the influence of pre stress loss of the anchor rope on the surrounding rock mass deformation and stress state was analyzed. The rationality of the simulation method and the feasibility of the support measures was analyzed by comparing the simulation results with the measured results. The results show that the max horizontal displacement occurs at the middle of the sidewall, while the max vertical displacement occurs in the top of the arch, and in the intersect area of the cavern the deformation is significant. The simulation results are very close to the measured results which can show the actual excavation process and the deformation characteristics of the surrounding rock mass. The horizontal displacement significantly increases when the pre stress loss in anchor rope comes to a certain degree.
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