曲弦钢桁加劲连续梁桥挂篮施工监控

随着挂篮在大跨径桥梁悬臂浇筑过程中的广泛应用,由于设计和施工不当所致的挂篮坠落事故时有发生。以曲弦钢桁加劲连续梁桥为工程背景,介绍三角形挂篮系统的前吊杆、后吊杆、模板、操作平台和走行系统,采用外置式的钢弦应变计监测不同工况下的前吊杆和后吊杆的内力,并与理论值进行对比分析。结果表明,吊杆的实测内力值略低于理论值,靠近箱梁腹板处的吊杆内力值最大,且随着吊杆距离的增大而减小,应予以重视。研究成果可为今后类似同类施工提供参考。

With the extensive application of hanging basket in the field of cantilever construction of large-span bridge,the falling accident of hanging basket induced by the improper design and construction frequently occurs.Based on the construction of a continuous girder bridge stiffened by curved chord steel truss,triangular hanging basket system,including front hangers,rear hangers,formworks,operation platform,and walking system are introduced.The test results of internal force of front hangers and rear hangers under different operating conditions were monitored by external steel string strain gauges and compared with the theoretical data.It is found that the test data of internal force of hangers is less than that of the theoretical data.The internal force of hangers near the box girder webs is the largest,and decreases with the increase of the distance of hangers,so attention should be paid on.The research results can provide reference for similar construction in the future.