Model Modification And Performance Evaluation Of Continuous Rigid Frame Bridge In Service Based On Optimization Algorithm

With the "12th Five-Year" National Transportation civil engineering,the new bridge is particularly prominent;the "13th Five-Year" bridge enters a stable development period,and it has become the focus of the project and a hot research topic for the performance evaluation of the existing bridges.Bridge modeling is the foundation of bridge performance analysis.The accurate analysis of bridge structure is closely related to the accuracy of the model.Due to the general error of theoretical modeling and actual structure,how to establish a high precision simulation model has become a hot research direction.The design parameter model updating method is one of the commonly used correction methods.The modified object is clear in meaning and widely used in civil engineering structural analysis.As the model correction method has more selectivity,the model correction problem is gradually transformed into a mathematical optimization problem,and the complex structural model can be accurately corrected by using the optimization algorithm.This paper briefly introduces the basic method of model correction,introduces the modification process and limitation of the first order optimization method,focuses on the swarm intelligence algorithm,based on the inertia weight to optimize the particle swarm optimization,and uses practical engineering to verify its reliability.Then,in view of the existing continuous rigid frame bridge and combined with the existing performance evaluation methods,a reasonable method is selected for performance evaluation.Finally,based on the evaluation results and theoretical basis,the main causes of bridge diseases are analyzed,and reasonable and economical reinforcement suggestions are given.The main contents and achievements of this paper are as follows:(1)The selection and process of model updating method are described,and the limitation of finite element ANSYS model optimization algorithm is introduced,and an optimized particle swarm optimization algorithm is introduced.The Sphere function and the Griewank function are iterated separately to prove the reliability of the optimized particle swarm optimization.The calculation results show that the optimization method isfaster than the standard method.Then the first order method and the optimized particle swarm optimization method are applied to the theoretical model and the actual project respectively,and the optimization results are compared to verify the applicability and reliability of the optimized particle swarm optimization algorithm.(2)Through the calculation of the continuous rigid frame bridge in service by using different status scoring methods,it is concluded that the use part of the more serious parts of the disease or the technical scoring method of the component can be more accurate.On the basis of research on existing cracks,the relationship between crack width and carbonization of concrete,crack width and corrosion amount of steel bar is analyzed,and the relationship between crack width and durability is introduced.(3)Based on the results of the bridge performance evaluation and the field survey data,the reasons for the formation of the main diseases are analyzed.In view of the causes,the reasonable suggestions for reinforcement and maintenance are given,which can provide reference for similar reinforcement and maintenance bridges.