三峡工程地下电站开挖的粘弹性数值模拟及稳定性评价

Viscoelastic numerical simulation and stability evaluation on excavation process of underground power station of TGP

以现场与室内岩石蠕变试验成果为基础 ,采用广义开尔文模型作为三峡花岗岩的粘弹性模型 ,对三峡工程地下厂房的施工开挖进行了粘弹性数值模拟。结果表明 :当考虑岩体的流变特性后 ,围岩的变形约增加了 5 %～10 % ,洞室围岩在各开挖步下的变形通常持续 7～ 10d趋于稳定。

Based on creep test results in situ and in laboratory on granite of Three Gorges Project(TGP), the viscoelastic numerical simulation on excavation process of the underground hydropower plants was performed by using the generalized Kelvin model as viscoelastic model of granite.The calculation results show that the deformations of the surrounding rock mass increase by 5 to 10 percent when its creep characteristics are considered,and the deformations of rock mass under each excavation step may last 7-10 days and approach to stability.