The Study On Single Rib Tied Arch Reinforcing Long Span Continuous Rigid Frame Bridge

Long-span continuous rigid frame bridge has been widely used, because it is reasonable forced, its construction is convenient, and driving on it is comfortable. With this type of bridge operating, its unique diseases gradually revealed. Such as long-term deflection appearing on the middle of the bridge, box girder webs producing diagonal cracks. These diseases are serious threat to the normal use of the bridge.At present, this type of bridge are using reinforcement method of external prestressing.On the basis of analyzing long-span continuous rigid frame bridge’s disease, expand the research on single rib arch structure reinforcing continuous rigid frame bridge’s method. The idea of this reinforcement method is that building a single rib arch structure on Girder is to change the bridge’s structure. The main contents are as follows:(1) Introduced span continuous rigid frame bridge characteristics, development and disease. Describes the current span continuous rigid frame bridge reinforcement method. The new structure reference beam arch combination structure. This paper briefly describes the types and mechanical characteristics of the beam arch composite structures.(2) Box girder webs producing diagonal cracks and long-term deflection appearing on the middle of the bridge is caused by many factors. The main factors are prestressing loss, shrinkage and creep effect,concrete cracking, construction. Finite element software is to simulate actual stress state of the bridge. and determine a reasonable state reinforced rigid frame bridge.(3) This paper analyzes the impacts of rib alignment, span ratio, suspender force on the structure of the force, and determine the design the initial parameters of reinforcement system.(4) The bridge in Foshan as an engineering background, establishing a finite element model of. continuous rigid frame bridge which is enforced by Single rib tied arch, and rational optimization the system, determining the design parameters of the reinforcement system, analyzing the effect of reinforcement.(5) contrast on the effect between reinforcement method of external prestressing and the new reinforcement method.The results show: This reinforcement method is reasonable. It can ensure continuous rigid frame bridge carrying capacity and limit state meet the relevant regulatory requirements after strengthening. It can be found that in the same degree, the effect of reinforcing ribbed tied arch structure better. Results of this study can provide reference for large-span continuous rigid frame bridge reinforced design, and it is with practical significance.