Whole Continuity Model For Optimization Of Arch Dam

Based on the new results of domestic and overseas, this author uses the structure optimization design, finite element, numeric method, and structure multi-objective optimization theories to investigate some problems about linear optimization model of arch dam, which includes the shape and mechanics characteristics of the arch dam. They are listed as follows:Firstly, In order to establish a new linear optimization model of arch dam, the surface shape of arch dam is analyzed using duality multinomial with 13 variables, the thickness at any location is obtained from the difference of coordinate values between upriver and downriver surfaces of arch dam, and the whole shape of arch dam is finalized from the equation with 26 variables. This linear model can allow us to obtain the analytic information of the dam surface, and at the same time, it can avoid the disadvantages of the nonlinear model such as: more load, slowly convergence and low precision.This author proposes the linear model and the related system, derive the linear expression which includes all the boundary conditions, and obtain the linear relationship between the dam volume function and variables, which meets the requirement of linear optimization of dam shape.Secondly, This author proposes that it is better to use analytic sensitivity method when only several variables are in a complicated dam problem after investigating advantages and disadvantages of sensitivity calculation methods, such as Whole-difference method, half-analytic sensitivity method and analytic sensitivity method. The analytic formulas and derivative formulas on temperature loads vectors, surface loads vectors, gravity loads vectors, and rigidity matrix are derived based on design variable. We obtained the formulas on node displacement vector and node stress vector after analyzing the characteristics of dam loads and related formulas. The high level terms are ignored in Thelar expression of structure stress, so we obtain the analytic linear expression of node stress based on design variable.Thirdly, considering the minimum dam volume or the maximal tensile stress as the objective function, in this dissertation, Xiaowan arch dam is taken as an numerical example to prove the feasibility of linear optimization model which is proposed by this author. It...