Cantilever Casting Construction Technology of Reinforced Concrete Main Arch Ring of ShaTuo Bridge

Abstract

Reinforced concrete box-ribbed arch bridge by suspending crane cantilever casting method has unique advantages in the construction of bridge in mountainous areas. However, with the increase of bridge spans, it not only puts forward higher requirements on the safe and efficient operation of construction equipment, but also increases the difficulty of the internal force control of the arch ring. In order to solve these problems, this paper takes the ShaTuo Bridge of Guizhou Province as an example and illustrates main technical solutions focusing on these three core contents: the suspending crane system, the anchoring system and the internal force control during construction of the main arch ring of the mountain arch bridge by cantilever casting method. The suspending crane adopts the structure of upside-down triangle suspending crane with divided principal truss, and the walking hanger is separated from the anchoring rod to realize the light weight and modularization of the suspending crane structure. Using the automatic correction system for real-time collection of the buckle tower offset information to rectify the deviation of the buckle tower in real time to ensure the safety of the anchoring system. The internal force of the arch ring is effectively controlled by providing temporary prestressing tendons in the arch box and the practice shows that the new technical means and methods used in subtilized control of the whole process of the construction ensures the safety of the main arch ring and the temporary construction structure, and also makes the internal force meets the design requirements both in arch box construction process and the completion state, which has a good reference value on the construction of similar arch bridges.