500m级钢管混凝土拱桥施工控制

为解决500 m级钢管混凝土拱桥施工控制的难题,对既有施工控制方法的局限性进行了分析.根据结构在施工过程中的力学特征,提出了施工控制的可调域法,并对该方法的计算公式进行了推导.基于可调域法的优点和拱肋拼装的要求,给出了吊装线形控制方法.可调域法通过将结构的线形、应力以及索力控制在一定范围内,只在关键施工阶段进行调整,从而减少了调索次数.将该方法应用于波司登大桥,合龙后线形和应力误差均在规范JTG/T F502011允许范围内.实践表明,可调域法在500 m级钢管混凝土拱桥施工控制中是可靠的. 

Construction Control of 500 m Scale Concrete- Filled Steel Tubular Arch Bridge

In order to solve the problems in construction control of 500 m scale concrete-filled steel tubular (CFST) arch bridges, the limitations of the existing construction control methods were analyzed. Based on the mechanical characteristics of the structure in construction process, an adjustable domain method for construction control was proposed, and the corresponding calculation formulas were deduced. From the preponderances of this method and the requirements of arch rib assembling, a line shape control measure for assembling was given. By controlling the line shape, stress and cable force to a certain range and adjusting them only in key construction stages, the adjustable domain method can reduce cable tension adjustment. The proposed method was applied to the Bosideng bridge, the errors of line shape and stress after closure were both within the allowable ranges of JTG/T F502011. The practice shows that the adjustable domain method is reliable for the construction control of 500 m scale CFST arch bridges.