Initial Form Optimization Of Monolayer Prestressed Cable Roofs

This paper did research on initial form optimization of monolayer prestressed cable roofs. Cables must be in tension in cable structure, and it have no stiffness without prestress. Cable roofs need to find the specific prestress system to maintain the geometric form. It has many parameters and the objective function is not explicit in study on form optimization. In order to solve these problems, this paper chose genetic algorithm as study method after widely contrast.Genetic algorithm is an adaptive global search optimization algorithm based on probability. This paper systematicallyintroduced genetic algorithm and its basic composition. According to the feature of cable structure this paper set up the genetic algorithm based on improved parallel method and improved best reserved method.In order to make the optimization process more efficient, this paper used MATLAB to operate ANSYS to complete the optimization. And the key point of exchange of these two kind of software was solved in this paper. This method was proved by example of optimization on ten stick truss.This paper established the process of initial form optimization on wheel-shaped monolayer cable roofs by improved genetic algorithm. Proper genetic operator was chosen. This paper established the simplified model of cable roofs. The optimization objective was the minimum investment, and the variables were form of cable roofs, cable section and prestress system. This paper simplified the variables to improve the optimization efficiency.This paper did research on the initial form of wheel-shaped cable roofs. According to the property that three cables are coplanarif they share the same node, this paper designed a method to establish the geometry shape ofwheel-shaped monolayer cable roofs. By this method the number of variables decreased. This paper designed a method of iteration to find the proportion of initial prestress of cable roofs.According to the optimization process of the wheel-shaped monolayer cable roofs, this paper conducted a study on a plurality of cable structure, and verified the feasibility of the use of genetic algorithms on the initial form optimization of wheel-shaped monolayer cable roofs.In this paper, the calculation model and load cases of the cable roofs of Suzhou Industrial Park Stadium were reasonably simplified, and the improved genetic algorithm was used to optimize the initial shape of the cable roofs. The characteristics of wheel-shaped monolayer cable roofs were summarized. In addition, the paper optimized the geometric model which was in line with traditional design, and compared with the original one. The conclusion was that the height difference and initial prestress of the cable roofs had a greater impact on the steel consumption, while the coordinate of the support nodes had a less impact. It was pointed out that the position of the supports could be determined according to the aesthetics of the building, and in order to find a reasonable initial prestress, the basic value of the initial prestress He and the prestress adjustment coefficient μ could be taken as optimization variables.