等壳碾压混凝土重力坝层间抗滑稳定可靠度分析

针对以有限元为基础分析碾压混凝土重力坝层间可靠度其功能函数不能显式表达的特点，采用响应面法、JC法、窄界限法原理相结合的可靠度计算方法。由三维非线性有限元对等壳水电站碾压混凝土重力坝各随机变量分位点值的计算结果，采用抗剪断公式构建该电站非溢流坝段层面的功能函数，求得响应面方程，并应用JC法和窄界限法计算层间单元可靠度指标及层间体系可靠度指标，进一步分析材料的变异系数对体系可靠度的影响。结果表明，φ是影响体系可靠度指标的最敏感因子，碾压各层β值一般为4.16～5.70，层间体系可靠度β'为4.12，满足工程要求。该方法计算效率高，实用性强，用于碾压混凝土重力坝层间抗滑稳定可靠度分析是可行的，值得推广。

A Reliability Analysis of Antiskid Stability between the Layers of Dengke RCC Gravity Dam

For finite element analysis of RCC gravity dam based on the reliability of its functions between layers can not be explicit expression of function characteristics, a calculation method on the structure reliability that combines response surface method ,JC method and narrow bound method, is established in the RCC gravity dam of Dengke hydropower station in Yunnan province.Based on the calculated results that use different quantile values of 8 random parameters by 3D non-linear finite element method, shearing resisting, the reliability function of non-flow gravity dam is deduced. Then, the response surface function, reliability index of layer systems and elements is calculated by JC method and narrow bound method,and also analysis the effect of coefficient of the materials on the reliable indexes of system. The results show thatφis the most sensitive factors of systematic reliable indexes, and the the value of β is between 4.16 and 5.70, β' is 4.12. It reflects that the method can get good precision, high performance, and well practicability. The new method is proved to be a good means in the structure reliability analysis of atiskid stability between the layers of RCC gravity dam, it is worth popularizing.