Analysis Of Reinforced Concrete Truss Arch Bridge Diseases In Service And Strengthening Methods Research

Under the restriction of the social and economic conditions of the corresponding technical level is limited,after 20 years of operation,especially in nearly a decade of overload operation,many of the truss arch bridge has emerged a large number of diseases,can not adapt to the current of the increasing traffic demand.So the analysis of bridge diseases and strengthening methods of research is the current urgent task,fuqing south gate bridge strengthening project,the author of this paper conducted the following research contents:(1)The development history of truss arch bridge are introduced,and its significance in strengthening,and in view of the arch bridge reinforcement principle are briefly expounded the basic principles and requirements of arch bridge reinforcement and reconstruction.And for the reinforcement method of truss arch bridge,briefly expounds the paste steel reinforcement method and enlarged cross section method,the adjustment on the arch construction dead load reinforcement method,external prestressed strengthening method,steel support reinforcement method.(2)based on15+3×30+15m truss arch bridge as the research object,using the finite element analysis software MIDAS/CIVIL,beam element model is set up,the level of highway-II live load and under basic load combination bridge static and dynamic analysis of the study of the truss arch bridge bearing capacity and the main diseases of the configuration forms,it is concluded that the original design load level is low,the structure is weak,poor quality of construction,the inherent defect of three aspects are the main cause of truss arch bridge diseases in service.(3)In fuqing south gate bridge reinforcement project as the background,the combination of the original bridge design drawings,design standards and design specifications and the actual bridge appearance test and load test data and results,the original bridge put forward three different reinforcement scheme:steel reinforcement method,the external prestressing method and enlarged cross section method of bottom chord.Then software MIDAS/CIVIL is used to build model of truss arch bridge,on three different reinforcement schemes and the original bridge static and dynamic characteristics and stability of the analysis and comparison,comprehensive analysis conclusion is:adopt steel support reinforcement design scheme is compared with other two kinds of reinforcement scheme can significantly increase the integral stiffness of the bridge,enhance the structural overall stability.In view of the above,this paper recommends the steel support to reinforce fuqing south gate bridge.