Shape optimization of concrete arch dams considering stage construction

This paper describes a methodology to develop the interface between a finite element software and optimization algorithm for optimization of concrete high arch dams. the objective function is the volume of the dam. the numbers of design variables are 31 including the thickness and upstream profile of crown cantilever, thickness of the left and right abutments, radius of curvature of water and air faces left and right by use of polynomial curve fitting and cubic spline function. the constraint conditions are the geometric shape, stress, and the stability against sliding. initially, a program is developed in matlab in order to generate the coordinates of nodes; then, finite element software ansys is taken for modeling the geometry of dam. finally, the optimization technique is performed by simultaneous perturbation stochastic approximation algorithm. to include dead weight of dam body, stage construction is considered. the proposed method is applied successfully to an arch dam and good results are achieved. the results indicate that the concrete volume of the optimized dam is reduced by an average of 21%. compared with the initial shape, the time of convergence in this method is very short and the method is fairly effective. it can be applied to practical engineering design.