用非概率理论分析混合不确定性结构的可靠性

A reliability approach based on non-probabilistic theory for structures with hybrid uncertainties

针对不确定性结构可靠性分析中的输入变量分布参数具有不确定性和输入变量为区间模型的混合不确定性结构展开研究。考虑到可用信息最少的情况,将分布参数的不确定性描述为区间模型。通过等概率转换方法将随机变量与其分布参数进行分离,使问题转化为随机与区间变量混合的可靠性问题,建立了混合不确定性问题的可靠性分析模型。基于非概率可靠性理论,建立混合不确定结构分析模型的二级极限状态函数并结合Kriging代理模型建立了高效的求解方法。将所建立的混合不确定模型应用于飞行器结构的不确定性分析中,验证了所建模型的合理性和所提方法的高效性和准确性。

Investigation on mixed structures with hybrid uncertainties was based on the reliability analysis of uncertain structures of the distribution parameters of input variables that acted as the interval model.Considering the available information was quite scanty,the uncertain distribution parameters were treated as the interval model.The reliability analysis model for this hybrid uncertainty was established by separating the distribution parameters from their random variables through using equivalent probability transformation method.Based on the non-probabilistic reliability theory,a high efficient solution method was proposed by successively constructing the limit state function of the proposed hybrid uncertain analytic model in two levels and combing the Kriging surrogate model.The proposed hybrid uncertain analytic model is employed to analyze aircraft structures with hybrid uncertainties,which can demonstrate the rationality of the proposed model and the efficiency and accuracy of the solution model.