预应力混凝土连续箱梁桥维修加固与监控

Reinforcement and Monitoring for Prestressed Concrete Continuous Box Girder Bridge

某预应力混凝土连续箱梁桥在长期运营过程中出现箱梁下挠、斜向裂缝及U形裂缝等病害,严重影响桥梁运营安全,文章对其加固设计进行介绍。通过增大腹板截面、增加体外预应力索及重做桥面铺装等措施提高箱梁刚度,改善箱梁整体应力水平,提高箱梁压应力储备。梁体应力及挠度的监测结果表明,箱梁顶、底部具有较大的压应力储备,裂缝闭合明显;荷载试验检测表明,梁体的强度和刚度校验系数均满足规范要求,达到预期加固效果。

In this paper, reinforcement design is introduced for a prestressed concrete continuous bridge in long-term operation, which appears deflection and crack diseases. Treatment measures such as increasing web section, adding external prestressing cables and bridge deck pavement resurfacing are used to improve stress level and compressive stress reserves of box girder. Monitoring results show that there are large compressive stress reserves in top and bottom of box girder, and crack closed obriously. Load test shows that the strength and rigidity check coefficient of beam meet the specification requirments and reinforcement effect is satisfied.