中文摘要：

为确定影响预应力钢结构体系可靠度的关键构件，从概率分析的角度出发，编制基于蒙特卡罗法的APDL程序，计算得到各个参数的灵敏度；通过分析各构件刚度同等程度的减小所引起的结构体系可靠度的降低，得到各构件的可靠性影响系数；然后由线性加权方法得到构件的权系数方程，从而建立起一种评判影响结构体系可靠度关键构件的计算模型，最后利用某弦支梁工程实例说明了该方法的应用．分析表明，所建议的方法能够准确体现构件权系数的含义，反映出各个构件对结构整体可靠性的影响程度，从而较好评判出结构的关键构件．

英文摘要：

Based on the probability theory and using the Monte Carlo method, a program is written by APDL language to evaluate key component for the prestressed steel structure. By which, the sensitivities of the correlated variables are calculated. The reliability influence coefficients of structural components are given through computing the decrease of structure system reliability caused by the component stiffness decrease. Then the weight coefficient equation is deduced by linear weighted method. A computational model of key components is thus determined. A practical example of beam string structure is given for the purpose of illustrating the strategy. The result shows that this method reflects the true physical meaning of the structure component weight coefficient and the influential degree of components on the whole structure system reliability. So the key component can be well estimated.