Evaluation And Analysis Of Construction Safety Risk Of Xigu Yellow River Super Large Bridge

In recent years,the construction of China’s transportation infrastructure has developed rapidly.As an important hub of transportation routes,bridges play a pivotal role in the construction of transportation infrastructure.However,in terms of safety risk assessment and risk management,especially for construction For cable-stayed bridges that are complex,difficult to construct,and have a long service period,there are many risk factors in the construction process,which have already posed a major threat to people’s lives and economy.The correct assessment of the safety risks in the bridge construction stage is used to ensure the safety of construction.Effective control becomes the best means to achieve disaster reduction.Therefore,in the process of further improving the construction of transportation infrastructure,building an overall bridge construction safety risk assessment index system,strengthening the risk management of the bridge construction stage,and controlling the probability of risk are of great significance to improving the safety of bridge construction.Based on the Xigu Yellow River Bridge,this paper studies the safety risks of the overall and special construction of the cable-stayed bridge as follows:Firstly,this paper reads and summarizes the domestic and foreign literature on construction safety risks and bridge construction accident cases,expounds the theories and procedures of risk management,and sorts out the general process of bridge construction safety risk assessment.Secondly,based on the Xigu Yellow River Super Large Bridge Project,an expert investigation method is used to identify the risk sources for the overall construction of bridge safety.It is classified and screened from six aspects of environmental conditions and bridge scale,construction technical risk,survey and design risk,human resources risk,organization management risk and traffic risk,and finally selected 20 factors which have a significant impact on the overall construction safety risk of the bridge,such as bad geological conditions and unqualified construction quality.By consulting the "Guidelines for Safety Evaluation of Highway Bridge and Tunnel Construction Safety(Trial)" and the bidding documents of the Xigu Yellow River Super Large Bridge,94 risk factors that have a greater impact on the special construction were identified by factor analysis.Finally,on the basis of the risk sources,build a bridge overall security risk evaluation index system,and with reference to the risk rating standards,set up a bridge the low(I),moderate(II),high(III),and extremely high(IV)four level of evaluation set.A cloud model-based overall safety risk assessment model for the bridge is proposed,which is weighted using the entropy weight method and combined with the evaluation set to determine the overall construction safety risk level of the Xigu Yellow River Super Large Bridge,the results show that the overall construction risk level of the Xigu Yellow River Super Large Bridge is height(Ⅲ).In order to get the special construction risk level,based on the analytic hierarchy process(AHP)to empowerment of each specific risk factors for accidents,and improved LEC method is used to evaluate the risk level of each special accident,the results show that the Xigu Yellow River bridge on the special risk accident level mostly Ⅲ level.Meanwhile,according to the risk level,corresponding safety countermeasures and risk prevention and control measures are proposed.The research results show that the cloud model can solve the ambiguity and randomness of the overall risk assessment process of the bridge.Meanwhile,the improved LEC method enhances the scientificity and rationality of the special accident risk assessment results due to the introduction of the risk correction coefficient.The evaluation results are consistent with the actual situation of the Xigu Yellow River Bridge.The evaluation method used in this paper can provide a reference for the safety risk assessment of other bridges,and has a positive significance in reducing the possibility of safety accidents.