中文摘要：

为了研究工程中可靠指标计算方法,提出了基于结构可靠度概念和最优化理论中的罚函数法,将结构可靠指标（RI）的求解问题转化成相应的无约束最优化问题,利用SCE算法良好的全局搜索能力,对相应的优化问题进行求解。利用Matlab平台设计了求解结构可靠指标的专用计算程序SCE-RI和MC-RI,并应用于某圆形隧道的可靠指标计算问题。通过与其他方法计算结果的比较表明：SCE-RI算法不仅能够避免功能函数求导运算困难,而且精度和效率都很高;用SCE-RI算法进行结构可靠指标计算是可行的,对其他类似工程有一定的推广应用价值。

英文摘要：

In order to study the reliability index calculation method in engineering structure,the calculation problem of structural reliability index（ RI） was converted to a corresponding unconstrained optimization problem by means of structural reliability concept and the penalty function method of optimization theory. In the solving process,the shuffled complex evolution（ SCE） algorithm was adopted because of its better global search ability. The special codes SCE-RI and MC-RI based on the SCE algorithm and Monte Carlo method were designed through the platform of Matlab. And these programs were used to compute the reliability index of a circular tunnel. By comparing with the calculation ones obtained by other methods,the results show that the SCE-RI algorithm can not only avoid the difficulty of function derivation operation but also have good performance in precision and efficiency. Moreover,the SCE-RI algorithm proposed for structural reliability index calculation is feasible and has certain application value for other similar projects.