基于高效搜索方法的可靠性分析改进响应面法

Aimed at the problems of large amount of calculation and low iteration efficiency of response surface method which is widely used in structural reliability calculation, an improved response surface method based on hybrid weighting of sample points and variable-direction search of reliability index is proposed. Firstly, based on the weight selection strategy of the traditional response surface function, a hybrid weighting method considering not only the distance between the sample point and the design point but also the limit-state-function value of the sample point is constructed. Secondly, due to the inefficiency problem of the traditional first-order second-moment method in each iteration of response surface, an effective search of design points based on the variable-direction search algorithm in each iteration process of response surface is realized. The numerical examples show that the method has good convergence and greatly reduces the number of iterations under certain calculation accuracy. And the maximum failure point and reliability index can be obtained accurately.