基于广义Lambda分布逼近的结构可靠度计算方法

Method for structural reliability analysis based on generalized Lambda distribution approximation

提出了基于广义Lambda分布逼近的结构可靠度计算方法。首先利用功能函数抽样数据,估计功能函数的前4阶矩信息。通过点估计法获得功能函数概率密度函数广义Lambda分布近似表达式,并根据工程结构可靠性的定义计算结构失效概率,进行可靠性分析。数值算例表明,广义Lambda分布对各种经典分布曲线具有良好的适应性。通过两个工程算例与Monte-Carlo模拟结果进行对比,验证了所提可靠度计算方法的正确性和实用性。

A method for structural reliability analysis based on generalized Lambda distribution was proposed.The first four moments for the performance function of structures were estimated by the sampled data firstly.Then the approximate generalized Lambda distribution for the probability density function of the performance function was determined by point estimation method and the failure probability of structures was evaluated by the definition of structural reliability directly.Numerical case studies showed that the generalized Lambda distribution has excellent ability to match several famous distributions.Finally,the accuracy and efficiency of the proposed method were verified by comparing with the Monte-Carlo simulation results of two engineering examples.