Construction Safety Risk Management Of Metro Double-track Station Excavation Research

During the process of construction,the underground excavation of urban metro has the characteristics of large concealment,strong cyclical working,limited working space,passing through various buildings and pipelines underneath,complex engineering geology and hydrogeology,multiple cross and transformation of construction methods as well as great pressure of construction period.It shows high risks that not only casualties,but also serious social adverse effects and huge economic losses of the country shall be caused once an accident occurs.Therefore,it is very necessary to study the safety risk management of underground excavation project in urban metro.Metro plays an active role in solving traffic problems in urban development.Combining with the excavation project of one metro station with double side drift method,this paper discusses the specific methods of implementing risk control in construction site from risk identification,risk assessment,risk countermeasures and other aspects of risk control.The main methods include the following contents: first,WBS-RBS method combined with expert investigation method shall be used to identify the risk problems of station excavation construction in seven aspects of safety management risk,surrounding buildings and surface subsidence risk,arch collapse risk,blasting operation risk,temporary electricity risk,demolition of temporary support risk as well as social risk,to find out the specific risk factors affecting these risk sources,and obtain the risk list.Second,AHP(analytic hierarchy process)shall be adopted to evaluate the risk of station excavation construction,and different risk levels shall be established based on evaluated data and the weight of each factor affecting the risk.Third,as for the various key risk factors of the station excavation,special solutions shall be formulated first combining with potential danger risk identification and governance system to eliminate risks in the bud,to ensure the construction safety of metro underground excavation station in double side drift method.To sum up,according to theoretical methods of risk management combining with specific engineering practice projects,this paper starts from the background of urban traffic development to carry out risk management of urban metro underground excavation station in double side drift method.Based on the basic contents and methods of risk management,identify risk factors and categories,evaluate the various risk factors that affect the excavation of underground metro station through qualitative and quantitative methods,and do a good job in the related deployment of risk management measures and potential risk identification and governance for the key risk factors to provide security for the excavation of underground metro station construction.