本文以拱坝拱圈线型值点坐标、拱端厚度和半中心角为体形参数给出了三次样条线型拱圈的构造方法,并给出了三次样条拱轴线的保凸条件;以拱冠梁和拱圈体形参数为设计变量,建立了三次样条线型拱坝体形优化设计模型。以某拟建拱坝体形优化设计为例,采用有限元等效应力描述应力约束条件,利用加速微种群遗传算法求解。计算结果表明,三次样条线型拱坝优化体形比设计部门经过优化提出的抛物线体形坝体体积减小了58.4万m^3,说明三次样条线型拱坝体形的优越性。
The coordinates of nodes,semi-center angle and the thickness of arch abutment are regarded as the shape parameters for establishment of arch dams with cubic spline.On the basis of convexity-preserving condition of cubic spline and setting the parameters of central cantilever beam and configuration of arch ring as design variables,an optimization model is established for shape design of arch dam with cubic spline.The design of an arch dam with this type is given as an example with the stress constrains condition described by finite element equivalent stress and solved by using the accelerated micro genetic algorithm.The calculated result indicates that the concrete volume of the arch dam optimized by the proposed cubic spline is less than the original design scheme optimized using parabolic shape by 5.84×10^5m^3.