三峡左厂抗滑稳定性影响的有限元分析

Study on effect of sliding stability of No.3 dam foundation of left powerhouse of Three Gorges Project due to No.4 dam foundation combined action using finite element method

根据实际产状建立了包含41条长大结构面及5条断层的三峡大坝左厂3号坝段和4号坝段联合作用的三维有限元模型,研究了左厂4号坝段对3号坝段深层抗滑稳定安全系数的影响。提出了一个基于三维强度折减有限元法计算结果确定坝基稳定安全系数的实用判定方法,该方法物理意义明确。分析结果表明,4号坝段对提高3号坝段的安全系数有一定的帮忙作用,但作用不大。

3D-FEM computation model included 41 items large structural planes and 5 items faults in the real attitude and distribution in the No.3 dam foundation and No.4 dam foundation of left powerhouse of the Three Gorges Project combined action are created. The safety factor of No.3 dam foundation in deep sliding stability due to No.4 dam foundation combined action is studied A new practical judge method of dam foundation stability safe factor based on 3D-FEM simulation results using strength reduction method is proposed; it has definite physics meaning. It shows that the combining action of No.4 dam foundation can increase the safety factor of No.3 dam foundation; but its effect is small.