Effect of segmental joints on structural deformation in long-span prestressed concrete box girders

In order to analyze the effect of segmental joints of box girder on structural deflection in long span cantilever casting prestressed concrete continuous rigid frame bridges, the FE models considering both construction processes and long-term deformations in existing bridges were established. Reduction in shearing stiffness was adopted to simulate weakness of segmental joints of box girder, and the effect of shearing deformations induced by weakness of segmental joints was analyzed. The results showed that the shearing deformations of segmental joints could lead to the significant increment in completed deflection and long-term deformation, only under the premise of remarkable decrease in shearing stiffness of segmental joints. In practical bridge structures, the determination of shearing stiffness of segmental joints after crack is a key problem for this effect. Whether or not the shearing deformation and shearing creep can contribute to continued deflection in long-span prestressed concrete box girder needs to be verified by enough experiments.