高拱坝安全分析中的不确定性因素研究

Uncertainty Factors in High Arch Dam Safety Analysis

为解决高拱坝确定性评价的弊端,综合应用概率统计理论、结构可靠性原理与风险分析等非确定性方法进行高拱坝安全分析。利用统计推理与假设检验研究了影响高拱坝失效的洪水水位、地震加速度及材料参数的分布规律与估计量的算法,利用二阶矩法计算了高拱坝失效模式的发生概率。分别利用确定性与非确定性方法对某高拱坝进行了安全评价,通过比较表明:利用失效概率、风险值两个指标对高拱坝进行安全评价可以兼顾安全性、经济性的平衡。

A suggestion is made to solve the problems by means of integrated application of such nondeterministic approaches as probability statistics theory, structural reliability principle, as well as risk analysis. By means of statistical inference and hypothesis test, a study is made of the distribution regularity and estimate algorithm of such factors causing high arch dam failure as flood level, seismic acceleration and material parameters. The occurrence probability of high arch dam failure mode is calculated by means of second-moment. A safety evaluation is made to a high arch dam by means of both deterministic and nondeterministic approaches and the comparison shows that applying both failure probability and risk value to high arch dam safety evaluation is desirable in terms of both safety and economic aspect.