| At present,with the increasing popularity of gas,the mileage of urban buried gas pipelines has also increased.However,it differs from other pipelines in that the surrounding environment of urban gas pipelines is complex,risk factors are variable,and the population is dense.Once an accident occurs,it will have serious consequences.Therefore,measures need to be taken to ensure the safe and stable operation of urban gas pipelines.In this thesis,by deeply studying the characteristics of gas pipeline accidents and the differences between gas pipelines and long-distance pipelines,a comprehensive risk assessment index system for buried gas pipelines was established.Based on the combination of cloud model,analytic hierarchy process,and Delphi method,a semi-quantitative risk assessment method was proposed.Based on Bayesian network,a quantitative risk assessment method for gas pipelines was proposed.This thesis takes the gas pipeline of a large city as an example to verify the two methods and compare the methods.The results show that the research method proposed in this thesis is reasonable and fits reality.The semi-quantitative risk assessment method can better express the ambiguity of expert comments and improve the objectivity of risk assessment results.The quantitative risk assessment method can accurately describe the process of accidents and the probability of consequences through numerical values,find out the law of risk evolution,and provide theoretical support for accident prevention and emergency decision-making.In the actual application process,the gas company can choose the appropriate method for evaluation according to the specific situation. |
