Research On Risk Assessment Methods For Landslide Disasters In Gas Pipelines

With the fast development of economist in China,the demand of natural gas is soaring.The source and the consumption market do not locate in the same place,which have stimulated the construction of long distance natural gas pipeline in China.Meanwhile,the long distance natural gas pipeline always confronted with all sorts of geological disasters,landslide is one of them,which is common and maybe result serious consequence.At present,there many studies in mechanics theory and risk evaluation respectively in worldwide,however,few researcher have put up with risk evaluation based on mechanics analyses of the pipeline which across landslides.In order to refine the risk evaluation,this paper is based on mechanics analyses to study the risk evaluation.Here is the main content of the paper:(1)Analytical methods and finite element methods are adopted to analyze the stress condition of natural gas pipeline,by which,the consequence is acquired,i.e.the most dangerous parts locates at the middle of the pipeline and the conjunction of sliding area and non-sliding area.The FEM model is validated by Analytical methods.Considering the condition of pipeline,stress failure criterion is recommended.(2)In the paper,the sensibility index method is used to analyze main factors in order to figure out their influential law and rank them by the importance,which would be the basis of risk mitigation measures.(3)The risk assessment model of the pipeline which across landslides have been built.Firstly,three aspects of the failure probability evaluation index system are established,including the cause of disaster factors,the degree of sensitivity to the disaster and the situation of monitoring governance.Then,security,economy and environment,those three aspects of the failure consequences evaluation index system is established.The consequences of failure of the gas pipeline are analyzed by two-tuple linguistic information.Finally,the risk matrix is used to determine the risk level of the gas pipeline landslide hazard.(4)Based on the above studies,the suggestions to mitigate the risk is put forward form the pipeline design and operation,the two perspectives.(5)The risk assessment method is used to a section of China West-East natural gas pipeline,and the result is according to the authentic risk assessment report.The study in this paper is a complement for the risk assessment of the pipeline which across landslides,which have set a theoretical foundation to assure the safety of the natural gas pipeline operation.