Schwedler型球面网壳的有限元分析及优化设计

【作者】 孙尚；

【导师】 刘海军；

【作者基本信息】 西北工业大学 ， 结构工程， 2007， 硕士

【摘要】 网壳结构，兼有杆系结构和薄壳结构的固有特性，受力合理，覆盖跨度大，是一种国内外颇受关注，有广阔应用前景的空间结构。 随着网壳结构的广泛应用，网壳结构的优化设计也倍受关注。现有文献中关于球面网壳的优化设计大多限于截面积的选择，或者先进行网格尺寸优化，再进行截面优化的分部优化设计，这些优化方法对网壳结构的优化设计都做出了贡献，但都因没能同时考虑设计参数间的最佳配合，而是先者仅为后者的基础或取值的依据，因而无法达到最佳的优化效果。本文以Schwedler型球面网壳为例(有限元模型选择空间梁单元)，采用对网壳曲率半径、网格尺寸和杆件截面积同步优化选择，即形状优化设计。优化结果表明总造价降低了19.1％，优化效果显著。除结构应满足强度、变形等设计要求外，同时还考虑到网壳结构是一种缺陷性敏感结构，在大雪、强风和地震荷载作用下，结构可能丧失整体稳定性，因此，还要对优化所得的网壳作稳定性全过程分析，从而验证优化设计是可靠的。 许多工程在使用期间将不可避免地受到风激、地震、爆炸以及来自其它外界环境的振动或冲击干扰作用，动力损伤或破坏将是其主要的失效形式。本文仍以Schwedler型球面网壳为例，对代表结构动力特性的频率和代表结构动力响应的变形进行动力优化设计，取得了理想的效果。更多还原

【Abstract】 Reticulated Shell structure, has inherent properties of the pole structure and thin shell structure, be subjected to dint reasonable, over lay to across one degree big, is kind to be subjected to concern rather at home and abroad, has vast application foreground of space structure.Along with the extensively applying of Reticulated Shell structure, the optimization design is extremely paid attention to doubly. In the light of the present documents has imperfections about the fact that the optimization design variable has been only limited to the sections, or carrying on separate optimization design in which carrying on optimization of the size of net first and then optimized the sections, these optimization methods have not reached the best optimization result. In the text , taking Schwedler Reticulated Shell as an example, I propose comprehensive optimization design method that is shape optimization .design variable including the shelly radius、net size (the shelly nodes number and the layers number)、the diameter and thickness of steel tube, the result of optimization indicate that the cost reduce 19.1 percent, The result is remarkable. Besides satisfy the desire of the stress constraints and deformation, we also consider that Reticulated Shell is a kind of structure is sensitive to deficiency, load under the heavy snow, high wind and earthquake, the structure may lose stably, so we will carry on the stability analysis to the structure and get the result to Satisfy the stability request.Many engineerings will be inevitably aroused by gale defying, earthquake, explosion and vibrate or impact interference effect from other external environments, dynamical damage or destruction will be the Main expiration form, in the text, taking Schwedler Reticulated Shell as an example, carrying on dynamical optimization design in which design variable including the frequency and transform, has obtained the ideal effect.更多还原