【作者】 李东斌；

【导师】 荣见华； 杨端生；

【作者基本信息】 长沙理工大学 ， 工程力学， 2007， 硕士

【摘要】 结构拓扑优化是优化技术中最具挑战性的研究领域,是一种创新性的设计方法。本文针对连续体结构拓扑优化设计问题,研究和分析了国内外在结构渐进优化法方面的发展状况。桥梁结构一般受到恒载(结构自重)和活载(车载等)的作用,结构恒载是与结构设计相关性载荷。当桥梁结构的初始设计结构所占的空间远远大于最佳设计结构的空间时,恒载的影响远远大于活载的影响,为了确保最佳设计结构的活载传递路径,本文用效率活载替代活载,以便增强活载的影响。在此基础上导出了结构的位移灵敏度和应变能灵敏度公式。而后,本文提出了一种涉及恒载和活载的多工况多约束的渐进结构优化方法,并给出了考虑应力和位移要求的多工况渐进结构优化算法以及考虑应力和应变能要求的多工况渐进结构优化算法。探讨了斜拉桥钢索预应力的施加方式,提出了多工况多约束的空间桥梁结构的拓扑优化设计方法。对上述方法进行了编程及大量工程结构的仿真计算。算例结果表明了本文提出的方法是正确和有效的,并显示具有较好的工程应用前景。更多还原

【Abstract】 Structural topology optimization has been treated as one of the most challenging tasks in structural optimization design, and is an innovative approach. For the problem of topology optimization designs of continuum structures, this thesis summarizes and analyzes the present status and the development of Evolutionary Structural Optimization method.Generally speaking, bridge structures are subjected to the dead load(structural weight)and the live load(automobile load etc.). The dead load is a design-relative load. When the space occupied by the initial design structure is much larger than the space occupied by the optimum bridge structure, the effect of the dead load is more and more important than the effect of the live load on structural optimization designs. In order to make sure that the optimum design structure is of reasonable transferring live load path, and enforce the effect of the live load on structural optimization designs, the live load is replaced by an efficiency live load in this thesis. Then, this thesis proposes a new evolutionary structural optimization method dealing with multiple load cases, multiple constrains, the dead load and the live load. And this thesis gives a set of algorithm of the evolutionary structural optimization method considering stress and displacement requirements and multiple load cases, and a set of algorithm of the evolutionary structural optimization method considering stress and strain energy requirements and multiple load cases. Moreover, this thesis makes researches on the loading way of steel cable pre-stressed of cable-stayed bridges, and proposes a spatial bridge structural topological optimization method with multiple load cases and multiple load cases and multiple constraints.For the mentioned-above proposed methods the procedures are implemented, and some simulation examples dealing with bridges are given. Results obtained show that the proposed methods in this thesis are correct and efficient, and are of good engineering application value.更多还原