Research On The Key Technology Of Construction Control For Concrete Filled Steel Tube Arch Bridge With The Cable Hoisting Process

In the recent thirty years, due to the advantages of concrete-filled steel tube arch bridge, such as beautiful alignment, reasonable load, convenient construction etc, the study of CFST (Concrete-Filled Steel Tube) arch bridge is becoming incandesced and technology has been developing rapidly at home and abroad. In view of the bridge, which is the long-span steel-tube concrete arch, there are certain difficulties in the erection of arch rid and times of structure system changing during the construction process. To ensure the arch rib and deck alignment meet the requirements of the design code, corresponding construction control measures should be taken. Taking Jialing River Bridge in Nanchong city as the engineering background, the key problems in construction process is analyzed in this thesis. The major research contents and conclusions are listed as follows:(1) Combined with the relevant materials on the CFST arch bridge at home and abroad, a summarized account of the development process and the division of the structural system of the bridge are presented in this thesis, including the structural characteristics and the arch rib section type of the bridge. The development prospects of CFST arch bridge is evaluated comprehensively. The research situation, which is related to the construction methods and construction control of CFST arch bridge so far, is summarized.(2) Applying the method of stress-free status in the construction control for concrete filled steel tube arch bridge with the cable hoisting process, the finite element model is established, getting the unstressed length of arch rib and suspender after calculation. Besides, the differences among current camber installation methods are given after comparing. Referring to the measured data of the bridge, the correctness of the suggested method is completely proved.(3) The cable force of construction can be acquired with the optimization of influence matrix, and the theoretical data is verified with the measured data.(4) Taking the structural stability coefficient as the evaluation index, the sequence of concrete pouring in the steel tubes is optimized. The causes of the phenomenon on the separation between the concrete and the steel tube are analyzed. Moreover, the corresponding solutions are pointed out in the thesis.(5) Based on calculation, the tie bar tension sequence and stage are optimized. Considering the actual situation of engineering site, the installation method of the bridge deck system is optimized. The practice shows that the method completely meets the need of construction.