Research On The Risk Assessment Of Electric Multiple Unit Operation And Maintenance In Chengdudong Electric Multiple Unit Operation Depot

In Chengdudong EMU(Electric Multiple Unit)depot,the daily safety risk assessment method adopted is mainly based on the safety check list,which is used by managers at all levels to carry out on-site supervision and inspection.With the expansion of EMU depot site and operation area,increase of maintenance task,the safety checklist method cannot be quantitatively analyzed in practical application,and the safety problem data summarized by the safety checklist method cannot be applied to the whole process.By summarizing EMU maintenance process and combining Work Breakdown Structure and Risk Breakdown Structure(WBS-RBS method for short),the current safety check list method is optimized by establishing EMU maintenance safety risk identification matrix and calculating the risk value of matrix element by the probability risk evaluation method.It is beneficial to carry out scientific safety risk assessment in the operation and maintenance of EMU,such as the working situation of staff,the safety situation on site and the quality of EMU equipment and facilities.First of all,based on the basic work responsibilities of the operation teams of the EMU,dividing the EMU operation and maintenance into two parts,namely "daily maintenance of EMU" and "online operation and maintenance of EMU",to complete the analysis of the operation process of EMU operation and maintenance.It lay a foundation for the subsequent determination of WBS tree establishment criteria and the establishment of WBS tree framework.Secondly,the WBS-RBS matrix was built by determining the WBS tree and RBS tree building criteria respectively.First,according to the basic theory of project scope management,the WBS tree decomposition modes of "daily maintenance of EMU" and "online operation and maintenance of EMU" are compared from five aspects of project life cycle,operation sequence,hardware composition,management department functions and functions.Finally,"decomposition in project operation order" is chosen as the EMU on-line operation and maintenance’s WBS decomposition tree mode.The combination of "carried out in accordance with the project management function decomposition" and "carried out in accordance with the project of the function decomposition" is select as EMU daily maintenance’s WBS decomposition tree mode.The EMU maintenance level 3 WBS tree is established.Second,based on the "health-safety-Environment" trinity management system(HSE),four safety risk indicators suitable for EMU maintenance workers’ health,operation safety,EMU operation safety and working environment were selected from five safety risk standards such as Occupational Disease Classification and Directory,Classification and Code of Hazardous and Harmful Factors in Production Process,and a two-level RBS tree is established.Thirdly,WBS tree is used as column coordinate of matrix element and RBS tree is used as row coordinate of matrix element to obtain the WBS-RBS matrix of EMU operation and maintenance.Then,based on the safety checklist method,the safety problem data discovered by managers at all levels in the operation of Chengdudong EMU in the past three years were collected.According to the statistical principle,the sample data were processed in three steps:pre-processing,compound grouping and frequency statistics,so as to prepare for the WBS-RBS risk identification matrix assignment.In order to improve the efficiency of matrix assignment,statistical software was used to calculate the frequency of WBS and RBS markers in 3748 security problem data used for matrix assignment,and the result of WBS-RBS matrix assignment was obtained.Finally,probabilistic risk assessment method was used to analyze and evaluate safety risks combined with safety problem data.Risk occurrence frequency and risk loss corresponding to each element in WBS-RBS risk identification matrix were calculated,and the corresponding risk value of each element was obtained.In risk loss analysis,in view of the safety problems’ s different levels and professions,the item by item assignment method for risk loss analysis process is used to add expert weight parameters.It can reduce the interference of subjective factors.In view of the fact that the text marks in the data of safety problems cannot be directly used in the calculation of risk loss,a single qualitative weighted scoring method is used to develop a 4-level risk loss rating for all the data of safety problems.Finally,according to the results of safety risk analysis,the evaluation is carried out from four aspects: employee health,operation safety,EMU operation safety and working environment,and countermeasures are formulated at the same time.