Study On The Mechanical Behaviors Of Steel Box-Concrete Composite Arch Bridge In Construction Stage

Relying on the “Performance and Analysis Research on Steel Box-Concrete ArchStructure” of the National Natural Science Foundation of China (51078373) and“Design and Key Construction Technologies of Vertical transfer on Steel-ConcreteComposite Bridge” of the Western Transportation Construction Science andTechnology Projects (200631881448), the mechanical behaviors of steel box-concretecomposite arch bridge during construction stage are researched with Chongqing JiangjinSunxi River bridge as engineering background. The main studies are as follows:①This paper takes Chongqing Jiangjin Sunxi River Bridge as engineeringbackground and has a detailed description on the structural and constructioncharacteristics of steel box-concrete composite arch bridge.②T he mechanical behaviors in the forming process of steel box-concretecomposite arch are researched in this paper. Aiming at the effect of flowing concrete tostructure, three type simplified methods to the dead load of concrete are studied. Theinfluence of different concrete placement sequence to structural performance isanalyzed and the optimal pouring scheme of concrete is proposed in this paper.③T he influence of temperatureeffect to structural performance duringconstruction stage is analyzed. With the continuous pouring of concrete and constantincreasing of composite section stiffness, the influence of temperature effect tostructural performance becomes flat. The temperature field of typical section in themain arch is also analyzed. With the continuous pouring of concrete, the temperaturefield of composite section has obvious slow down tendency, and the sensitivity totemperature also has slow down tendency.④Aiming at the steel box-concrete composite arch bridge with the span of100m,the construction method of making, transporting and hoisting two half arch ribs inposition is studied, and the reasonable construction process and precautions areproposed. The bias of monitoring data during construction stage is analyzed and thecorresponding processing method of data analysis is also proposed in this paper.