基于B样条曲线的自由曲面索支撑空间网格结构多目标形态优化

发布时间：2019-01-20 16:56

【摘要】：对自由曲面索支撑空间网格结构进行多目标形态优化研究。首先根据索支撑空间网格结构的建模方法,将优化结构整个曲面转化为优化结构的准线和母线。其次为保证优化后的自由曲面光顺,引进B样条曲线建立曲面,并将B样条曲线已知点作为优化变量。出于不同结构设计需要,选用力学指标和几何指标、或力学指标和经济指标、或不同性能力学指标组合作为多优化目标进行结构优化。得到结论如下:首先,采用本优化方法,优化前后曲面形状变化不大,适用于对给定初始曲面结构进行形态优化。其次,以应变能和用钢量为优化目标,属于融合了截面优化和形态优化的多目标优化,其对于索支撑空间网格结构效果较好,具有较高的工程实用价值。最后,以应变能和杆件长度均方差为优化目标,所得优化结果对杆长均方差和应变能加权系数变化不敏感,可满足杆长均匀性和结构力学要求。
[Abstract]:The multi-objective morphological optimization of free-form cable supported spatial grid structure is studied. Firstly, according to the modeling method of cable-supported spatial grid structure, the whole curved surface of the optimized structure is transformed into the alignment and bus of the optimized structure. Secondly, in order to ensure the fairing of the optimized free-form surface, the B-spline curve is introduced to establish the surface and the known point of the B-spline curve is taken as the optimization variable. In order to meet the needs of different structural design, mechanical index and geometric index, mechanical index and economic index, or combination of different performance and mechanics index are selected as multiple optimization objectives for structural optimization. The conclusions are as follows: firstly, the shape of the surface before and after the optimization is not changed by this optimization method, which is suitable for the shape optimization of the given initial surface structure. Secondly, taking strain energy and steel quantity as the optimization targets, it belongs to the multi-objective optimization which combines the cross-section optimization and the shape optimization, which has a better effect on the cable braced spatial grid structure, and has higher engineering practical value. Finally, the strain energy and the mean square deviation of the length of the bar are taken as the optimization objectives. The results obtained are insensitive to the variation of the mean variance of the rod length and the weighted coefficient of the strain energy, and can meet the requirements of the uniformity of the length of the rod and the structural mechanics.
【作者单位】：东南大学混凝土与预应力混凝土结构教育部重点实验室;江苏筑森建筑设计有限公司;
【基金】：国家自然科学基金(51278117) 国家杰出青年基金(51125031) 教育部新世纪优秀人才资助计划(NCET-13-0120) 江苏省六大人才高峰(2013-JZ-009)
【分类号】：TU399

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