极限状态响应面法分析结构可靠度的研究

一般响应面方法由于逼近的是功能函数而非极限状态方程,因而精度有时不高。为克服此不足,提出一种极限状态响应面法。该方法利用位于极限状态曲面上的样本点来重构结构的极限状态方程,因而模拟出的极限状态曲面精度较高。由此提出一种算法,通过逐步修正求解得到的设计点以实现在设计点附近较高精度地逼近结构真实极限状态方程。该方法同时克服了重构极限承载力曲面方法不能适用多个荷载随机变量的缺点。数值算例表明该方法具有较高的精度,适用范围广,而且所需样本点数量少。

Research on Analysis of Structural Reliability Based on Limit State Response Surface Method

The general Response Surface Method(RSM) sometimes provides a less accurate result since it approximates the performance function rather than the limit state equation.A method called the limit state response surface method is proposed.It uses the sampling points on the limit state surface and can obtain a good approximation to the limit state surface.Therefore an algorithm is developed to(approximate) the limit state equation accurately around the true design point through iterative modifications for the design point solution.It (also) overcomes the disadvantages that the method to restructure the ultimate load capacity surface should not be applied to the case with many load variables.Numerical examples show that the method is of precision and universality,in need of fewer sampling points.