Research On Risk Assessment Municipal Buried Gas Pipeline

Along with the increase popularity rate of city gas in China, Our country city gasindustry also obtained fast development, and the mileage of gas transmission pipeline is rapidgrowth. As the important component of city infrastructure, the safety problems of city gastransmission pipeline appear increasingly important because it carries a risk material. Riskassessment is the main technical mean used on pipeline safety management by currentcountries,it can effectively decrease and prevent leakage accidents.This paper studied city gas pipeline risk assessment by using fuzzy mathematics methodand index rating method. At first，it built a pipeline failure fault tree and detailedly analyzedall kinds of the cause of accident and their combination on the base of the analysis of gaspipeline leakage accident statistics data domestic and overseas; Then the pipeline risk can bedivided into four factors,such as pipeline corrosion factors, outside interference factors, pipeflaw factors and pipeline accessory equipment factors.Based on these,the paper establishedthe risk index rating system about city gas transmission pipeline and quantified the index aspoints.At last, Completing the analysis of quantitative risk assessment to city gas pipeline byusing the fuzzy comprehensive evaluation method.The key to fuzzy comprehensive evaluation is selecting fuzzy membership functions.Through the use of Matlab, the common membership functions are analyzed and compared.Then, this paper calculated the membership functions of high accuracy which are applyed topipeline risk assessment. Combined with the characteristics of the gas pipeline in Beijing，establish fuzzy comprehensive evaluation’s factor sets, comments set and confirm the weightfactors. As experiments shows,the evaluations of corrosion degrees of some pipeline sectionin Beijing which are based on survey data are accurate. Safety evaluation of city gas pipelinecan provide decision support for safe operation, reduce the incidence of accident and dailymaintenance work.