Research On Segmental Reinforcement Technology Of Continuous Rigid Frame Bridge

The early construction of prestressed concrete continuous rigid frame bridge in our country,because of the imperfection of the bridge structure design theory ? material properties and construction quality control is not enough,coupled with the increasing traffic volume ? maintenance management is not in place,there are many structural diseases of China's early construction of prestressed concrete continuous rigid frame bridge.Manifested as cracking and cross under the scratch,the light affect the structure of durability and aesthetics,serious impact on the normal use of the bridge,and even endanger the structural safety.According to the research needs of the China Communications Construction "changes in the structural system reinforcement and the whole span demolition technology research on Long-span concrete box girder bridge ",the paper puts forward that the intermediate span of the prestressed concrete continuous rigid frame bridge and the existing reinforcement method In the middle section of the main section of the segment replacement reinforcement method,that is,By reducing the structure of the structure,we can solve the problem of cross-middle problem,and improve the carrying capacity of the bridge.This article focuses on the work:(1)This paper summarizes the main diseases on the prestressed concrete continuous rigid frame bridge and its causes,the existing reinforcement methods and their advantages and disadvantages,to propose new reinforcement methods,which is to replace the existing concrete beam section with steel structure.(2)The design of replacement design of steel joint and steel box girder is put forward,and the construction technology of steel joint girder,steel box girder lifting,concrete pouring and prestressed tension are formed.Aiming at the whole process of replacement and reinforcement,the structural simulation model is carried out by establishing the whole structure model.(3)The finite element simulation model of the model bridge under the crack load is established before and after the replacement reinforcement.The crack load of the model bridge before the reinforcement is taken as the control load to calculate the deflection and stress of the main control section.The main parameters of the model bridge beforeand after reinforcement are compared and analyzed,and the effect of the reinforcement is improved.The rationality and reliability of the replacement reinforcement are proved theoretically.(4)The model test of reinforcement of concrete beams is carried out,and the design of bridge structure and test process is completed.