Study On Risk Evolution And Management For Third-party Damage Of Urban Natural Gas Pipeline

Due to the complicated surrounding environment of urban natural gas pipelines,third-party damage has become the most important cause of leakage and failure accidents.The dissertation is supported by the Research Project of Major Theoretical and Practical Issues in Science in Shannxi Province “ Research on Leakage Risk Evolution and Control of Urban Oil and Gas Pipelines in Shaanxi Province” and Special Scientific Research Project of the Shannxi Provencial Department of Education “Study on Dynamic Risk Evolution Method for Old urban Oil and Gas Pipeline Leakage under the Conditions of Information Uncertainty”.Based on the leakage accidents and the major explosion accidents caused by third-party damage of urban natural gas pipelines in China,the risk evolution mechanism,accident consequence assessment and management control of urban natural gas pipelines are carried out in response to problems such as the risk evolution process mechanism,the unclear consequences of the accident,and the chaotic control mechanism.Certain research results have been obtained in urban natural gas pipeline accident statistics,third-party damage risk evolution dynamic assessment,pipeline leakage accident flammable gas migration law and pipeline risk control mechanism,providing theoretical support for the prevention and control of urban natural gas pipeline third-party damage accidents.The main research details is as follows:1.Study on Accident Statistics and Catastrophe Evolution of Urban Natural Gas PipelineIn order to ensure the prevention of urban natural gas pipeline accidents,it is necessary to summarize and study the causes of urban natural gas pipeline accidents.This study combines the latest data reports of EGIG and domestic natural gas pipeline accidents to sort out the causes of urban natural gas pipeline leakage accidents,and analyze the causes of natural gas pipeline accidents.The catastrophic chain theory is used to construct the catastrophic evolution model of natural gas pipeline leakage accidents,and the key links in the natural gas pipeline catastrophic process are determined.The effectiveness of this method is demonstrated through case application analysis,and the management and control strategy of major natural gas pipeline accidents is studied according to the type of pipeline cause.2 Study on the dynamic risk evolution of third-party damage to urban natural gas pipelinesThe urban natural gas pipeline is located in a complex geographical environment and is easily affected by the coupling of surrounding environmental factors.To this end,this study sorts out the comprehensive risk factors of third-party damage to urban natural gas pipelines,and combines intentional and unintentional damage to construct a thirdparty damage accident scenario model for urban natural gas pipelines.Fuzzy set theory and Hierarchical Bayes(HBA)method are used to calculate the probability of basic events to solve the uncertainty caused by poor data.Based on the Bayesian network(BN),considering the conditional dependence relationship between risk factors,a dynamic risk evolution model of urban natural gas pipeline third-party damage is constructed.Using the probability of basic events as the data input,infer the probability of third-party damage and leakage accidents of natural gas pipelines,and update the pipeline leakage risk probability in real time based on the precursor data.Finally,the dynamic risk evolution probability is obtained,which provides protection suggestiong for third-party damage and leakage accidents of urban natural gas pipelines.3 Study on Consequences of Urban Natural Gas Pipeline Damage Accident Caused by Third-partyConsidering the evolution of combustible gas diffusion from urban natural gas pipelines and its risk assessment,a diffusion model of combustible gas from urban natural gas pipelines is established based on the CFD method to study the movement of combustible gas between urban buildings.Considering the explosive characteristics of combustible gas in accidental ignition scenarios,studying the effects of temperature,thermal radiation,and explosive overpressure on buildings and surrounding residents according to the burning and explosion injury criteria,and providing support for the prevention and rescue of urban natural gas pipeline leakage and explosion accidents.4 Study on third-party damage risk management and control of urban natural gas pipelinesAiming at the management and control of the third-party damage risk of urban natural gas pipelines,a three-party cooperative control mechanism of natural gas pipelines of "local government-pipeline operator-public" is proposed based on game theory.Combining the three parties’ strategic choices in the management and control process,analyze the benefits of the three parties under different strategies,and calculate the three-party coordinated control ratio based on the traditional static game theory.The evolutionary game theory is used to solve the dynamic evolution behavior of the three parties in the dynamic game process and the three-party evolutionary game SD model is constructed based on the system dynamics theory to explore the influence of external variables on the game process.The proposed management and control strategy recommendations provide throretical support for the risk management and control of urban natural gas pipelines.