拱坝线性破坏轨迹的随机分析

按三维连续体力学的随机有限元法分析拱坝，用不同的强度准则建立功能函数，用一次二阶矩法求拱坝的可靠指标场，指定可靠指标最小的点为破坏已经实现的事件，记录其相应的失效概率，之后，修正该点的刚度和拱坝的总刚，重复上述的分析过程，直至开裂稳定或溃坝。上述过程开裂点的几何位置的集合即为拱坝的破坏轨迹，条件概率的集合即为拱坝破坏轨迹的概率向量。

Probability analysis of linear cracking trajectories of arch dam

The 3-D stochastic finite element method for solid mechanics is applied to analyze the arch dam. The different strength criterions are used to establish the performance function. The reliability index field of arch dam is solved by first-order second-moment method. The point with minimum reliability index is identified as the emergence of cracking. Note down this failure probability and modify the stiffness of this cracked point and the whole dam accordingly. The cracking trajectory can be traced in accordance with the progression of cracking point by repeat this procedure. The conditional probability vector of cracking trajectory is in terms of the progression of conditional probability.