小半径曲线现浇箱梁张拉施工工艺及质量控制

Construction Technology and Quality Control of Prestressed Cast-in-place Box Girder with Small Radius Curve

现浇互通匝道桥半径较小,需要在很短的线型中完成交通流向的转变,纵横坡渐变。这些桥线型多样,桥梁结构受力复杂,尤其小半径曲线梁桥,除承受弯矩、剪力外,还受到扭矩和翘曲的作用。曲线预应力混凝土连续箱梁桥采用支架现浇,预应力后张施工工艺。预应力施工工序需要精细化控制,才能保证施工质量。本文以一座典型的曲线形预应力混凝土连续现浇箱梁桥为工程背景,对预应力连续箱梁张拉施工工艺进行了总结。

The radius of the ramp bridge is small, the traffic flow direction needs to be changed in a very short line, and the vertical and horizontal slope is gradual. These bridges have a variety of line types, and the structure of the bridge is complex. Especially the small radius curved beam bridge, in addition to bending moments and shear forces, is also affected by torque and warpage. Pre-stressed concrete continuous curved box-girder bridges adopts cast-in-situ support and post-tensioning construction technology. In order to ensure the construction quality, the process of prestress construction needs to be controlled in detail. Based on a typical curvilinear prestressed concrete continuous cast-in-place box girder bridge, this paper summarizes the tensioning technology of prestressed continuous box girder.