某特大桥连续刚构箱梁底板修复施工

REPAIR CONSTRUCTION OF BOTTOM SLAB IN A CONTINUOUS FRAME BRIDGE

某高速公路特大桥,由于施工阶段底板纵向预应力束张拉导致箱梁底板发生层状撕裂,须凿除底板后重新浇筑。修复施工过程中,张拉底板钢束后产生的压应力将从底板向全截面传递,为保证压应力能有效传递,采取了一系列施工措施,保证了结合面的粘结性能和抗剪能力,施工效果良好。

Because of tension of pre-stressed steel bar during construction, the bottom slab of a box girder bridge cracked transversely. And the slab must be removed and recast. After recasting of concrete, pre-stressed steel bar was tensioned again and the compressive stress was transferred from bottom to all cross-section in the repairing process. To ensure the effective transfer of the stress, some measures were taken to guarantee the bonding performance and shear resistance of connecting interface, reaching good construction effect.