基于流-固耦合的强度折减法在重力坝抗滑稳定分析中的应用

对传统强度折减法计算流程进行分析,指出了其中存在的不足,即对渗流的考虑不够充分.为弥补此项不足,从H-M耦合机理出发,推导了渗透系数与体积应变之间的函数关系,从而实现了H-M完全耦合.借助ABAQUS软件子程序USDFLD的二次开发,实现了H-M耦合与强度折减法的结合.以一个典型的重力坝双滑面稳定问题为例进行了对比分析,揭示了渗流对于重力坝稳定性的影响不可忽视.最后,对某重力坝单坝段进行了考虑H-M耦合的强度折减计算,得到了该坝段的渐进破坏过程和强度储备系数.

Application of strength reduction method considering hydro-mechanical coupling to analyze anti-sliding stability of gravity dams

In the traditional strength reduction method,the influence of seepage is frequently overlooked.However,recent studies have shown the necessity to consider the seepage in bedrock,especially in the stability analysis of gravity dam against sliding.The relationship between the rock permeability coefficient and the volume-strain is deduced to achieve the hydro-mechanical coupling.An USDFLD subroutine in ABAQUS is developed to implement the strength reduction analysis considering hydro-mechanical coupling.The anti-sliding stability analysis for a typical gravity dam with double sliding faces is then performed to demonstrate the effect of seepage in bedrock.Finally,the proposed strength reduction method considering hydro-mechanical coupling is applied to a gravity dam.The damage process and strength reserve safety coefficient are obtained.