Study On Reasonable State And Performance Of Cable-stayed Bridge

In this paper, the author takes an example which based on a long-span building cable-stayed bridge, the study focuses on the influence and it's regularity for change of reasonable finished dead state, reasonable construction state, tower and beam synchronous construction, and other structural parameters of hybrid girder cable-stayed bridge have been developed.At first, a practice method to obtain the prestressing force of cables, which determine the initial finished dead state of cable-stayed bridge is proposed, based on the objective of minimum bending energy, and combined with the influence matrix method. Through theoretical analysis and calculation and in accordance with the example of the simple structure, this method has been proved to be simple and effective, by the constant optimization of other methods. Then, the initial finished dead state of the relying on the project has been determined by this method succsessfully.Second, the paper is based on the theory of influence matri, and proposed the iteration method, which asking for the reasonable construction state. Detailed analysis is carried out, with the example of simple linear structure, the paper proves that the method is valid. Moreover, considering for several nonlinear factors, the reasonable construction state of the relying on the project has been determined based on this method, and the result of analysis shows that the method is easily toapplied and effective.Third, the finite elements of synchronous construction method and unsynchronous construction method of ower and beam is discussed was set up. It has obvious advantages: shorten the construction period, cost savings, and economic. But there are also several difficulties:for examples, how to control the deviation of main tower and how to formulate a specific program. In this paper, with a comparison of this method and traditional methods, the influencing factors are analyzed, and a quantitative calculation is conducted. Finally, the control limits and control methods are proposed.Last, the paper based on the parameters of relying on the project, the deviation sensitivity analysis has been carried out.Therefore,the dead-weight of structure,temporary load, structural stiffness, initial cable tension and concrete creep and shrinkage have a greater impact on the cable tension, main beam deflection and stress and structural stiffness of smaller deviation. As hybrid girder cable-stayed bridge, stiffness and initial cable tension deviation of the deflection of steel girder and internal forces cause more significant influences, so these parameters should be managed and controlled strictly in the construction process and simulate accurately.At the end of this paper, the author makes a brief summary of research work, gives some research conclusion that based on the current research situation, and points out some problems which need to be further studied and solved.