Optimum Analysis And design of Curved Concrete Dams

Abstract

This study discusses and clarifies the general steps for best analysis and shape design of a curved dam with double curvature depending on the model chosen by the dimensions mentioned in this study. To achieve the goal above the finite element method is adopted for the analysis of arch dams using tetrahedron element with 10 nodes implemented in (SolidWorks) , commercially available code program. The design of the basic shape of the dam has been done by using horizontal curve and vertical curve equations. After conducting the design and analysis of the initial model by SolidWorks, it is transferred to the second phase. This is the shape optimization process by using Genetic Algorithm in Matlab program. At this stage to calculate the volume of the dam body (considered as the objective or goal function), integration method is used to convert the volume of the dam to an equation in terms of the design variables (tc1, tc2, tc3) which represent the thicknesses of the dam at three levels. Then this equation has been moved to Genetic Algorithm tools using (m-file) to complete the optimization process. The results show that the best design shape of the dam is the model (9) of thicknesses (5.5m, 13.3m, 19.8m).These are less than the initial model of thicknesses (10m, 30m, 40m) with maintaining the stresses within the allowable limits specified by the dam design specifications. The percentage of reducing thickness in the level at z=0 is 45% , at z= 90m is 55.6% and at z= 180m is 50.5% . The percentage of reducing total volume for the dam is 53.75% .The results are compared with reference [25] which used same model of arch dam .This reference made the optimization process in (GA) also but, by using (11) design variables while in this study only (3) variables are used and the other variables are chosen as constants or prescribed parameters. The volume differences between the two solutions is only 3.99%. This result gives a confident to the present study by using only a small number of design variables which represent the general shape of the arch dam accurately.