Research On Construction Safety Risk Assessment Of Long Span Bridge Engineering

With the rapid development of public and railway construction in China,and the rapid development of long-span bridge in new structure,new materials,new equipment and new technology,the number of long-span bridge projects is increasing.Bridge engineering in the construction process,by the influence of construction technology,construction conditions,construction environment and construction management factors,construction safety is facing great risks and challenges.Therefore,in order to effectively manage and control the construction safety of long-span bridge,it is necessary to systematically evaluate the risk factors affecting the construction safety of long-span bridge,and put forward countermeasures and suggestions.In this paper,risk identification,risk estimation and risk evaluation are mainly carried out from three aspects,using literature research,case analysis,Delphi method and neural network research methods,the construction safety risk index system and risk assessment model of long-span bridge engineering are established.The main research results and conclusions of this paper are as follows:(1)Through literature analysis and case study,35 construction safety risk factors of long-span bridge engineering are identified.According to the principle of index system construction,a construction safety risk index system of longspan bridge engineering including 5 first-level indexes and 35 second-level indexes is finally constructed.(2)Based on ACO optimization ability and BP neural network has strong nonlinear processing ability and self-learning ability,therefore,this paper combined the existing two methods to build the ant colony optimization BP neural network construction safety risk assessment model of long-span bridge engineering.(3)The risk assessment effect of the ant colony optimization BP neural network model was empirically analyzed through the MZW bridge example data.The results showed that the ant colony optimization BP neural network model could output more accurate results,which proved that the model was effective and feasible.At the same time,according to the results of risk assessment,the risk countermeasures are put forward for reference.The risk assessment model constructed in this paper can enrich the safety risk assessment method of long-span bridge construction and apply it to actual projects,thereby reducing the impact of risk factors on construction safety and ensuring the economic and social benefits brought by long-span bridge projects.There are 17 figures,40 tables and 103 references.