地下管道动力可靠性分析的降维计算方法

地下管道是城市重要的基础工程之一，对其进行的地震作用下的可靠性分析是地下管道安全性的重要指标．但传统的可靠性分析只是针对单根管道进行分析与实际情况存在一定差异．本文采用系统可靠性理论对地震作用下的地下管线动力可靠性进行分析，并针对系统可靠性计算量大的难题，引入了PNET法（point evaluation technique）与谱系聚类分析法两种降维方法，在保证精度的同时大大提高了计算效率，使对地下管线的系统可靠性分析达到实用化程度．最后还结合实例进行了系统可靠性计算并对两种降维方法做了比较分析．提出了相应改进措施．

Dimension Reduction Method for the Dynamic Reliability Analysis of Underground Pipelines

Underground pipeline is one of the important infrastructure constructions of the city and its reliability analysis under earthquake action is a key index of the security of underground pipeline. However, the traditional reliability analysis focuses on single pipe, which is different from the real practice. The reliability analysis theory of structural systems is adopted in this paper to study the dynamic reliability of the underground pipeline. Two dimension reduction methods of point evaluation technique and pedigree clustering analysis were applied to the large amount of calculation in the reliability analysis of structural systems. With satisfactory calculation accuracy and computing time, the proposed approach proves to be a practical method for dynamic reliability analysis of the underground pipeline. An example was developed using this approach,and the results of the two dimension reduction methods were compared,through which some improvement measures were proposed.