Condition Evaluation Of Prestressed Concrete Continuous Rigid Frame Bridge

Prestressed concrete continuous rigid frame bridge has many advantages, such as comfortable driving, good integrity, excellent seismic performance and many other advantages, it plays an important role in our country’s traffic network. With the natural aging of structure, increase in the number of vehicles and effect of overload, it appears some diseases, such as mid-span deflection and crack, its condition catches engineers’attention increasingly, In order to play the role of prestressed concrete continuous rigid frame bridge in traffic network better, it’s crucial to evaluate its condition.On the basis of summarizing predecessors’research results, according to the structural characteristics and bearing capacity factors of PC continuous rigid frame bridge, based on load test of Qinjiang third bridge, the condition of Qinjiang third bridge is evaluated by fuzzy comprehensive evaluation theory, the following research work were done in this paper.1Finite element model of Qinjiang third bridge and the corresponding transverse, longitudinal, vertical prestressed reinforcement are built. Modal analysis and sensitivity analysis of Qinjiang third bridge are carried on, the design variable, state variable and objective function are carried out. Qinjiang third bridge model is updated with ANSYS software.2Based on Qinjiang third bridge finite element, the effect of temperature, prestress loss, pier foundation settlement, mid-span deflection on continuous rigid frame bridge is researched, the results show that they have a big influence on the interia force of PC continuous rigid frame bridge and have little influence on the frequecies of PC continuous rigid frame bridge, they should be got enough consideration in bridge design phase. 3Classification standards of condition evaluation are studied, continuous rigid frame bridge condition evaluation model is established. Based on analytic hierarchy process and principle of variable weight, weight of each index is studied. The index evaluation standards of main beam, bearing, pier, abutment are researched.4Static and dynamic load test results of Qinjiang third bridge were analysed. The fuzzy comprehensive evaluation method is used to evaluate Qinjiang third bridge’s condition. The condition of Qinjiang third bridge is good, its bearing capacity meets the requirements, and its evaluation result is consistent with load test results, only normal naintenance is required. Finally, condition evaluation program of Qinjiang third bridge was preliminary written.