大跨度钢管拱异位拼装整体纵移施工监测

Construction Monitoring of Long Span Steel Tube Arch Ectopic Assembly Integral Longitudinal Movement

以一座大跨度连续梁拱组合桥为工程背景,开展钢管拱异位拼装整体纵移施工监测技术研究,对钢管拱在施工过程中的应力、变形和整体稳定性等力学行为进行施工监测,并同有限元分析结果进行比较,保障大跨度钢管拱的安全施工要求。监测和有限元分析结果表明,在异位拼装和支架拆除阶段,钢管拱的应力和位移偏差不大,其大小受临时拉索索力大小的影响较大;在整体纵移阶段,钢管拱运行平稳,其稳定性受横向风荷载影响较大。在启动和制动时刻,钢管拱的水平加速度有明显波动,竖向加速度波动不明显。根据钢管拱施工监测分析结果,表明钢管拱在施工过程中的线形、应力和位移等力学特征均满足规范要求。

Based on a long-span continuous composite bridge of concrete-filled steel tube arch, the construction monitoring technology for the overall longitudinal movement of steel tube arch ectopic assembly is studied. Compaired with finite element analysis simulations, the mechanical behaviors such as stress, deformation and stability of steel tube arch are monitored in the construction to ensure the safety construction requirements of long-span steel tube arch. During the stage of ectopic assembly and support removement, the monitoring and finite element analysis results show that the stress and displacement deviation of steel tube arch is not large, and the magnitude is greatly affected by the temporary cable force. In the overall longitudinal stage,the steel tube arch moves smoothly, and its stability is greatly affected by lateral wind load. At start-up and braking time, the horizontal acceleration of steel tube arch has obvious fluctuation, and the vertical acceleration fluctuation is not obviously. According to the monitoring and analysis results of steel tube arch, it is shown that the mechanical characteristics such as alignment, stress and displacement of steel tube arch in the construction process meet the specification requirements.