深圳证券交易所营运中心抬升裙楼施工阶段应力监测与分析

In-construction stress monitoring and analysis of floating platform of the New Headquarter of Shenzhen Stock Exchange

深圳证券交易所营运中心的抬升裙楼采用超长巨型悬挑钢桁架结构体系,具有悬挑跨度大、受力复杂、临时支撑卸载难度大的特点。采用自主研发的基于有线应变数据采集与无线信号传输的应变监测系统,在施工阶段,尤其是在卸载过程中,对抬升裙楼关键构件进行实时应力监测。通过长期应变监测数据统计分析、双轴对称测点应力对比分析以及焊接对结构局部应力增量影响试验研究,对施工中的抬升裙楼进行实时安全评估。结果表明:卸载过程中裙楼结构受力稳步转换;龙骨焊接施工产生的焊接残余应力对焊接区域附近的结构局部应力增量有显著影响。

The New Headquarter of Shenzhen Stock Exchange is featured by its mega-overhanging floating platform which is a long-cantilevered steel truss structure.In recognizing the uniqueness of the floating platform in terms of the long-span overhanging frame,complicated loading conditions,and challenging dismantlement of the temporary supports,a novel strain monitoring system by integrating tethered data acquisition and wireless data transmission was developed to continuously monitor the strains of key structural components of the floating platform at the construction stage,especially in the process of dismantling the temporary supports.In-construction real-time safety assessment of the floating platform was conducted through statistical analysis of the long-term strain monitoring data,comparison analysis of the derived stresses at bi-symmetrical sensor locations,and experimental study of the welding effect on the local stress increment.The results show that the stresses of the floating platform evolve in a step-by-step manner synchronously with the unloading process,and the keel welding will generate the welding residual stress which has a significant effect on the local stress increment of the structural component at the welding-affected zone.