网架结构的拓扑优化与鲁棒性分析

发布时间：2018-01-04 02:00

本文关键词：网架结构的拓扑优化与鲁棒性分析　出处：《浙江大学》2016年硕士论文　论文类型：学位论文

【摘要】：目前规程推荐的网架结构形式,从结构的几何边缘到中心区域,杆件的拓扑一般是相同的。由于网架结构不同区域受力相差很大,从结构优化来看,采用整体相同的杆件拓扑形式,材料将得不到充分利用。同时,由于网架结构跨度大、构件多、破化后果严重,随着近年来频发的事故,对网架结构抵抗不相称破坏能力的分析愈发显得重要。因此,本文从结构拓扑优化及鲁棒性两方面,对网架结构进行研究。拓扑优化是近年来结构优化研究领域中的前沿课题。本文对结构优化方法进行了归纳总结,讨论了变厚度法、均匀化方法、变密度法和渐进式结构优化法等在工程中的实现方法。结合渐进式结构优化法,分别对周边简支切向约束和四点支承的网架结构给出拓扑形式。通过上述拓扑优化的网架进行满应力设计,得出杆件的截面尺寸,并与常规的网架结构进行用钢量、鲁棒性和极限承载力比较。采用H_∞结构鲁棒性评价指标,对正放四角锥、斜放四角锥、抽空四角锥、棋盘四角锥、正交正放桁架型、三向交叉桁架型等网架结构,通过参数分析,研究了几何参数、网格形式对网架结构鲁棒性的影响。通过适当更改网架的拓扑,得到提高结构鲁棒性的途径。采用不同位置四点约束方式,对网架进行结构鲁棒性的比较,从结构鲁棒性角度获得四点约束的适合位置。通过上述研究表明,渐进式结构优化对网架结构的优化是有效的,一般可以节约10%左右的用钢量；同时,通过计算不同网架结构的鲁棒性评价指标,可以得出网架结构的抵抗不相称破坏能力、合理拓扑改进、适合跨度范围和最佳约束位置等。
[Abstract]:The recommended procedures for the network structure form, from the edge to the center area of geometric structure and topological bar is generally the same. As the network structure in different regions of stress vary greatly, from the view of structure optimization, the topology of the same bar, the material can not be brought into full use. At the same time, because the span truss structure a large, multi components, due to serious consequences, as in recent years, frequent accidents, to analyze the structural resistance of disproportionate failure ability is more important. Therefore, this article from the topology optimization and robustness of the two aspects, to study the network topology optimization of frame structure. In recent years, the structure optimization research topic in the field of. This paper summarizes the structure optimization method, discusses the variable thickness method, homogenization method, variable density method and evolutionary structural optimization method and implementation method in engineering. Combined with the gradual. The optimization method of simply supported tangential topological structure is given constraints and supported by four points. The full stress design through the network topology optimization, the section size of bar, and the amount of steel and conventional grid structure, bearing capacity between the robustness and the H_ infinite limit. Structural robustness evaluation index, the positive four pyramid, four diagonal pyramid, four to four pyramid pyramid, chessboard, orthogonal truss type, three to cross truss type structure, through the parameter analysis of geometric parameters, grid form of grid structure robustness. Through appropriate changes network topology the improved way of structural robustness. The different positions of the four point constraint, compare the structural robustness of grid, obtained four point constraint for position from the structural robustness perspective. Through the above study, progressive The structure optimization of the network structure is effective, can save about 10% of the amount of steel; at the same time, by calculating the robustness evaluation index of different grid structure, incommensurate can draw the grid structure damage resistant ability, reasonable topology improvement, suitable for span and the best constraint location.

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU356

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