Optimization Of Cable Force Of Prestressed Concrete Cable-stayed Bridgesurface Method

Cable-stayed Bridges have developed rapidly in the last half century due to their excellent mechanical performance,reasonable structural characteristics,beautiful shape and economic cost.As the span of cable-stayed bridge increases,the optimization of internal force of cable-stayed bridge structure becomes more and more important.In this paper,a large prestressed concrete cable-stayed bridge is taken as the engineering background.The specific contents of this paper are as follows:1.This paper briefly introduces the development of cable-stayed Bridges at home and abroad,reviews the research status of reasonable completion state,reasonable construction state determination and cable force optimization of long-span cable-stayed Bridges at home and abroad,briefly expounds the basic concept of cable force optimization of cable-stayed Bridges,and puts forward the research significance and purpose of this paper.2.this paper discusses the basic concept of cable force optimization and the importance of the development,summarizes the cable-stayed bridge is reasonable according to the state of the bridge cable force determined method and the cable force optimization calculation theory as well as the cable force of cable-stayed bridge construction control and the initial cable force and the calculation method of comparative analysis of the different methods for the bridge and the applicable conditions of different construction process and the rationality of the calculation results,it is concluded that the reasonable choose the suitable method according to the actual situation of cable force optimization not only can save time and easier to the builder of the design to achieve the ideal effect.3.The finite element model of the whole bridge was built based on an engineering example,and the main steps of finite element modeling,necessary modeling preparation and key points needing attention were introduced.With bent can preliminarily determines the minimum method into the state of the bridge cable force,and calculation into the state of the bridge girder and cable tower of the bending moment and stress the feasible region and the maximum and minimum of suspension cable force based on the feasible region of the cable force by least squares optimization adjustment,improve the stress of the whole bridge state,to achieve the best state of reasonable into a bridge.The results show that the cable-stayed bridge can be determined effectively by the combination of several methods and the method of calculating the cables in several iterations step by step.4.Through finite element modeling,each construction procedure in the construction process of prestressed concrete cable-stayed bridge is simulated in the model,and the optimal control of cable force is decomposed into each construction stage,which can be timely and effectively adjusted.The reasonable tension force of stay cable in construction period is determined by means of the combination of formfitting iteration method and influence matrix theory.The results show that the optimal control of the cable force during the construction period and the optimal adjustment of the cable force after closure can well meet the predetermined requirements for the reasonable state of the bridge.