Study On Cable-hoisting Erection System Without Supporting Frame Of Long-Span CFST Arch Bridge

The Concrete-Filled Steel Tubular (CFST) arch bridge has achieved rapid development in recent years in our country and is becoming more long in the span and large in the scope. In the construction of long-span CFST the main methods are the erection with rotation method and the cantilever-assembling erection using cable-hoisting without supporting frame.In this thesis some research work of the cable-hoisting system is doing taking the Yonghe Bridge in the Nanning city as engineering background. The cable-hoisting system without supporting frame is a temporary suspension bridge appearing in the construction. It has strong geometric nonlinearity as well as the suspension bridge. The analytical method of this construction is various. The Corotational formulation method is applied in this thesis. The track cables, buckle cables, anchorage cables, wind resistance cables are simulated applying the large slack, small strain catenary elements. And the slipping, the tangent point variety of the track cables against the saddles are analysed in this thesis.An analytical program is developed applying the Visual Basic6.0 to analyse the cable-hoisting system. In this program a high efficiency solving method in the finite element solving—the improved iterative format SSOR-PCG method is adopt. And the database techniques and CAD drawing techniques are applied too. The interface of the program is very good. The solving using this program is very accurate through many solving examples comparing.The cable-hoisting system of Yonghe Bridge in the Nanning city is analysed based on the developed program. The main work is analysing the test of the cable-hoisting system. The slipping, the tangent point variety of the track cables against the saddles, the slack of the track cables, the loads of the track cables acting on the towers, the horizontal displacement of the towers are analyzed, and some rules are obtained. These rules are concordance with the data of the test of the cable-hoisting system. Furthermore the temperature influence to the horizontal displacement of the towers is analysed simply. The static analysis of the towers is doing simply to indicate that there is still some safety stock in the worst work condition.