中文摘要：

随机模型的分布参数是由随机试验结果进行统计推断而得出的，往往难以准确预知，将其描述为模糊变量是可行的。将模糊数学理论与可靠性分析相结合，对分布参数为模糊变量的结构体系模糊可靠性进行了分析，具体推导了两种失效模式间的模糊相关系数和二阶联合模糊失效概率的求解公式，求出了失效模式间不相关和相关两种情况下，结构体系模糊失效概率在各λ水平截集下的区间解，估算出了结构体系的模糊失效概率，并对加筋板结构的模糊可靠性进行了分析。通过算例表明该方法更符合工程实际，是有效可行的。

英文摘要：

The distribution parameters of a probabilistic model are usually obtained from statistic inference of random experiment results, and they cannot generally be forecasted with accuracy. It is therefore reasonable and feasible to describe them as fuzzy variables. By combining fuzzy mathematical theory and reliability analysis of structural systems, this article makes an analysis of the fuzzy reliability of structural systems with fuzzy variables as distribution parameters of a probabilistie model. The fuzzy correlation coefficient of any two failure modes and the solution formula of second-order fuzzy failure probability are deduced in detail, and λ cut numbers of the fuzzy failure probability of the structural system is carried out when the failure modes are either correlated or uncorrelated. Fuzzy failure probability of the structural system can finally be estimated. Fuzzy relia-bility of a stiffening plate system is analyzed as an application of the proposed method. Finally, a numerical example is considered to illustrate the practicability of the method.