Reliability Assessment of Corroded Water Transmission Pipelines Using Harmony Search Optimization Algorithm

Lifetime of pipelines is very important for safe water transmission and distribution systems. For this purpose reliability analysis is a good tool and made it easy to make decision for inspections during maintenance and utilization process. In this study a non-linear state model has been used for the structural analysis of corroded pipelines, stressed by external forces. External load and substance corrosion are considered simultaneous base on limit state function. In order to take the uncertainty associated with the design and environmental variables into account and obtaining failure probability (reliability index), a harmony search meta-heuristic optimization algorithm has been selected. Sensitivity analysis of associated parameters is carried out to measure the effectiveness of each ones on the probability of pipe failure. Results obtained for a steel water pipeline of Kash water transmission project are discussed as a case study.