Study On Maintenance Construction Risk Of Bridge And Tunnel Discipline In Urban Rail Transit Operation Period

As a low-carbon and environment-friendly travel mode,urban rail transit plays an increasingly important role in urban transportation system.Its operation system is a huge and complex integrated technical system,covering more than 20 specialties such as metro vehicles,communication,signal,power supply,track,housing construction,bridge and tunnel,integrated monitoring,ventilation and air conditioning,automatic fare collection,etc.The equipment and facilities are various.Through efficient equipment and facilities operation and maintenance,various professional systems can operate in a coordinated and stable manner to achieve safe passenger transport.The bridge and tunnel discipline is characterized by poor construction conditions,short operation time,high requirements for protection of existing facilities and equipment,many special operators,aging construction personnel,complex personnel structure,high labor intensity,construction operations usually require multi discipline cooperation,and low degree of mechanization.Therefore,the construction risk is high.Therefore,it is of great significance to analyze and study the construction risk of bridge and tunnel discipline.This thesis uses the combination of literature analysis method and expert survey method to identify the secondary(criterion level)indicators of the maintenance and construction risk of urban rail transit bridge and tunnel discipline: personnel risk,management risk,technical risk and environmental risk.The secondary indicators are further decomposed to obtain 16 tertiary indicators including the illegal operation of outsourced personnel,and the risk indicator system of maintenance and construction of urban rail transit bridge and tunnel discipline is established based on this.Then the weight of each risk indicator is determined by the analytic hierarchy process,and finally the risk assessment of maintenance and construction of urban rail transit bridge and tunnel discipline is carried out through the fuzzy comprehensive evaluation method.Through calculation,the management risk accounts for the largest weight,followed by personnel risk,environmental risk and technical risk,with the weight values of 41.49%,35.75%,13.69% and 9.07% respectively.This thesis sets up five comment sets of "serious","large","general","small" and "very small",evaluates each risk index through experts,and draws the conclusion that the risk of bridge and tunnel maintenance construction during the operation period of urban rail transit is "common" through calculation using fuzzy comprehensive evaluation method.From the perspective of secondary indicators,technical risk is a serious risk with low weight,while personnel risk,management risk and environmental risk are general risks.Through analysis,six factors affecting the risk of maintenance and construction of urban rail transit bridge and tunnel discipline are identified: illegal operation of outsourced personnel,fatigue at night,lack of safety education,short operation time,high degree of specialization,and the impact of work vehicles.According to the results of risk assessment,countermeasures are proposed for the risk of bridge and tunnel maintenance construction during the operation period of urban rail transit from four aspects: personnel,management,technology and environment.