The Impact Analysis Of The Long-term Deformation And Control Research For Long Span Continuous Rigid Frame Bridges

Big span continuous rigid frame bridge with its simple construction, no supports, without expansion joint, no system conversion, driving smooth as well as economy, with a wide range of application and development. But, in recent years, The excessive deflection of the big span continuous rigid frame box girder bridge has become serious problems, these deflection have influence the driving comfort, safety and the further development of the bridge in the transportation field.In view of the excessive deflection in the midspan of the large span continuous rigid, studied the concrete creep and the primary factor of influencing big span prestressed concrete continuous rigid frame of the later deformation; Finally forwarded some corresponding measures from the design and construction.First of all, four different span continuous rigid frame bridge had been under investigation and analyzed, prestressed and different parameters about the creep of the long-term deformation of long span continuous rigid frame bridge are studied.Second, because of these factor of influencing long pan continuous rigid frame bridge have some uncertainty; such as concrete creep parameters and the estimating prestressed loss.and it is difficult to calculate accurately. In this paper, from the factors of influencing the large span continuous rigid frame bridge, with an example of more span continuous rigid frame bridge of the (87+5×162+87)m of Jing river large bridge. building a finite element model, analyses the influence of the deformation of bridge; such as different loading age, environment relative humidity of concrete, prestress loss, and overweight and other factors, and along with the growth of the time, analyzes the chage rule of the long-term deformation of bridge.Third, To better analyzing the influence of the long-term deformation of large span continuous rigid frame bridge; and comparative analysis the theoretical and the measured values to linear and internal force of the newly built large bridge of Jing river.Finally, Analyzed the influence of the uneven settlement of pile caps for big span continuous rigid frame bridge to the long-term deformation. The physical properties of the foundation soil and the foundation of pile caps settlement are closely related, increasing over time, after a few years or decades of time, settlement of pile caps eventually get the final value. The settlement of pile caps will affect the linear of bridge, and the structure of the girder to generate additional internal force.