大型地下厂房洞室群围岩稳定分析

 锦屏一级水电站最大坝高305 m，为混凝土双曲拱坝，电站装机容量360×104 kW，总库容77.6×108 m3，调节库容49.1×108 m3，是目前已建、在建和设计中的世界最高拱坝，其设计难度处于世界最高水平。针对地下厂区围岩类别较低、结构面发育、高地应力场以及洞室群规模巨大等情况，应用损伤力学理论，对地下洞室群的稳定性进行三维非线性弹塑性损伤有限元模拟计算，以判定地下厂房洞室群布置、施工开挖顺序、围岩支护参数的合理性，并对数值模拟结果与地质力学模型试验结果进行对比分析。结果表明，数值模拟和模型试验结果基本吻合，地下厂房洞室群围岩的整体稳定状态良好。

STABILITY ANALYSIS OF SURROUNDING ROCK OF LARGE UNDERGROUND POWERHOUSE CAVERN GROUP

Jinping first stage hydropower station is a concrete double-curvature arch dam with a maximum height of 305 m. It has a total capacity of 360×104 kW，the total reservoir capacity is 77.6×108 m3，and the regulating capacity is 49.1×108 m3. It is the highest in the world，and its design complexity is at the world¢s top level. In response to the low surrounding rock classification，developed structure planes，high geostress and massive underground cavern group，the 3D nonlinear elastoplastic damage finite element method is applied to analyze and compute the stability of underground cavern groups to make certain the rationality of the layout of underground cavern group，the sequence of construction and support parameters of surrounding rock. By analyzing and comparing the numerical simulation results and geomechanical model experimental data，it is indicated that the numerical simulation results agree well with the experimental data. The stability of the underground cavern group satisfies the requests of design.