一种结构可靠性指标的搜索方法

提出了一种计算结构可靠性指标的搜索方法，即自动变步长搜索方法。该方法克服一次二阶矩方法的缺点，对于非线性功能函数非常有效。数值例题表明：这种方法具有很好的收敛性和较高的计算精度，且其收敛性与初始步长无关，可以用于复杂问题可靠度的分析。

A search algorithm for structural reliability index

This paper presented a search algorithm proposed for calculating the structural reliability index,which changes step automatically. The algorithm overcomes the fault existing in the first-order second-moment method.That is to say,even when the nonlinearity of performance function is comparatively high,the convergence can still be guaranteed.So the algorithm can change step automatically,so that it overcoumes some faults existing in other algorithms.For instance,convergence is decided by the selection of step can only depend on experimental calculation.The numerical results demonstrate that the algorithm has characteristics of better convergence and relatively high accuracy,and it can be used in analysis on reliability of complex problems.