基于变密度法的实体重力坝拓扑优化

Topology Optimization of Entity Gravity Dam Based on Variable Density Method

以ABAQUS为优化平台,基于变密度法,采用SIMP插值和RAMP插值2种模型对实体重力坝进行断面优化,结果表明:应用SIMP插值模型优化的坝体断面出现大量空洞且迭代次数多为50;RAMP插值模型优化的坝体断面符合实体重力坝坝形且迭代次数较少,证明RAMP插值模型更适用于实体重力坝优化。进一步对最优模型的下游进行直线和曲线拟合,并进行静力分析,结果表明:优化模型符合实体重力坝的各项应力和稳定性指标,且坝体下游设计为曲线形比直线形更能缓和应力集中区,在实际应用中更优。

SIMP( solid isotropic microstructures with penalization) interpolation model and RAMP( rational approximation of material properties) interpolation model are employed to optimize the section of entity gravity dam. The optimization is carried out with ABAQUS as platform based on variable density method. Results suggest that by SIMP method,a large amount of cavities occur in the dam section,which requires many iterative times( mostly up to 50); whereas by RAMP model,the dam section conforms with the shape of the gravity dam and the number of iteration is small,indicating that the RAMP method is more suitable. Furthermore,the downstream of optimal model is fitted by straight line and curve,and static analysis is carried out. Results reveal that the optimized model accords with the stress and stability indexes of entity gravity dam. Curved downstream dam shape is better than straight line in practical application,because the former could ease the stress concentration zone better than straight line does.