Study On The Risk Assessment Of Construction Safety For Bridge Engineering

In order to meet China's "The Belt and Road" development strategy,China's highway mileage is increasing,in which cross river,rail,canyon bridge works are also increasing rapidly.Therefore,it will continue to encounter new technology,Span length,large dead weight,and Complex interface environment and other challenges in the construction process.At the same time,in the construction of the project,the probability of safety accidents has already been a problem that can not be ignored.The Ministry of communications and transportation of China has issued a pilot guide in 2011,recommends and urges the construction units to carry out the construction safety risk assessment before construction,guarantees the safety of the construction process and improves the quality of the construction.At the present stage,the study of construction safety risk assessment in engineering field is still in its initial stage,so,it is necessary to explore and study the scientific and effective method of construction safety risk assessment.This paper takes the Weiri highway swivel bridge as the project background,and aims at exploring the method and theory of reducing the uncertainty of construction safety risk effectively.The article first refers to the risk acceptance criteria in the field of risk assessment,puts forward the information flow chart of bridge construction safety risk assessment,defines the relationship between the overall risk assessment and the special risk assessment,focuses on the theoretical models involved in the special construction safety risk assessment of Bridge Engineering.And,in this paper,the evaluation model based on ant colony algorithm and BP neural network is applied to the special risk assessment,it studies how ant colony algorithm optimizes BP neural network risk assessment model,and the selection of corresponding parameter variables.Secondly,the paper studies the evaluation principle of the classical index system and establishes a scientific risk estimate system.Relying on the Weiri high-speed swing bridge engineering,and the comparative analysis of risk assessment model based on ant colony algorithm and BP neural network,the paper adopts the way of a combination of experiment and experience to determine the number of ant colony,pheromone intensity Q,information volatility p.Finally,the finite element model is used to simulate the construction process of the most dangerous beam section of the rotor bridge,and the most unfavorable section position is pointed out.As the construction focus,it is easy to come up with the countermeasuresThe results show that the evaluation results based on the ant colony algorithm and the BP neural network model are basically the same as those obtained by the classical index system.So,The method is feasible,and it can be used for bridge construction safety risk assessment,and it can achieve the expected goal of the project.Besides,the method is applied directly to the special construction safety risk assessment,which is more targeted,and can take concrete risk pre control measures to manage major risk sources.