Design And Research Of Transverse Connecting Stiffener For Large Cantilever Concrete Box Girder Bridge Widening

The paper proposes a new connecting scheme between new and old box girder for triaxially prestressed box girder, which is using transverse stiffener connect new and old box girder. According to YanHe bridge lies in HuaiJiang Highway, the paper makes a systematical research about box girder's loaded performance after connecting and optimized analysis of the transverse stiffener size.At first the structure size of transverse stiffener is proposed according to differential settlement of foundation and deformation under live load. Internal force transfer is also discussed. Grillage model is established through Midas/Civil, to analyze the influence of the transverse stiffener size on internal force of box girder and transverse stiffener.The results shows that, the Broaden box girder bridge can meet the requirements of material safety performance under dead loads. Shrinkage and creep effect cause eccentric compression on broaden box girder and stiffener makes it possible to transfer internal force laterally. Differential settlement of foundation makes it easier for stiffener to have negative stress state. The stress and displacement values decrease obviously after connecting under live load.Change the size of stiffener has a small effect on the internal force of box girder, but has a big effect on the internal force of itself. So the internal force of stiffener is a priority when designing. Broaden box girder satisfies the requirements of ultimate bearing capacity and the normal service condition after Structural safety check.