The Load Test And Finite Element Model Modification Research Of The Reinforced-bearing Arch Bridge

As the channel throat of the national economy,the stand or fall of the bridge's technical condition is related to the national economic benefit.With the number of bridge in our country increasing,some old bridges,influenced by the construction level,environmental erosion,material aging,and other effects,often appear this or that disease and injury.At the same time,the continuous growth of traffic and the increasing load of vehicles also pose a threat to the capacity and carrying capacity of the bridge.If the safety analysis and maintenance of the bridge structure are not carried out,the bridge will occur sudden accidents,which will cause a large amount of waste and unestimated economic losses.Taking a steel-reinforced composite bridge deck supported suspender arch bridge as an example,this paper combined with the theoretical analysis with damage identification of a disease,the static and dynamic load test research,and model correction.key technical problems in the test are studied in this paper,such as the theory of finite element analysis of static and dynamic performance failure cases(including derrick structure safety analysis).The main research contents are as follows:Firstly,based on the finite element theory of bridge structure,the static dynamic finite element equation was established for the consideration of the static and dynamic characteristics of the geometrical system stiffness of the suspension rod arch bridge.By considering the geometrical stiffness of the derrick system and combining the construction stage with the displacement control,the space finite element model is used to analyze the calculation formula of the geometrical stiffness matrix and tension of the derrick system.Based on the reserch on derrick damage characteristics of half through arch bridge and the it's influence on analysis of finite element model,the damage and disease of the original bridge are detected by the appearance,and the strength and rigidity of the material were detected by the entity,The maintenance and reinforcement of the through arch bridge were carried out.With the purpose of understanding of the bridge's actual conditions correctly and providing the basis for the finite element model updating and theoretical analysis,appearance and entity detection were conducted of the reinforced bridge.Then,according to the identification of modal parameters of the bridge structure theory,with dynamic and static load test orgnized,the spectral peak recognition method was used to identify the modal parameters of bridge structures,static test research is used to determine the actual working state of bridge structure.In the end,the finite element model of the bridge is modified based on the damage and measurement error and dynamic load test of the bridge.By considering the finite element analysis theory of the geometrical stiffness of the derrick system and the construction process,the static performance of the brige is analyzed.According to the finite element analysis theory of the geometrical stiffness of the derrick system,the dynamic performance of the system is analyzed and compared.