论文部分内容阅读
文献[1]和[2]中指出,结构优化设计的目标函数和约束函数中包含有大量的模糊信息,提出了结构模糊优化设计的概念和物理量(结构反应和尺寸)在模糊许用范围下的α-水平截集解法。 本文进一步提出了抗震结构模糊优化设计的方法。为此定义了模糊预测烈度、模糊反应谱、结构的模糊反应,给出了具有广义模糊约束(包括模糊约束函数及其取值的模糊允许范围)的模糊规划的解法。文献[1]和[2]中所用的α-水平截集解法是它的特例。这个解法的基础是给出了模糊约束函数对其允许模糊取值范围的满足度的概念,并利用它把问题转化为一系列非模糊规划,从而得到一个最优点序列,这就为求解模糊规划奠定了基础。 在抗震结构优化设计中,第一步利用上述方法求得结构最小造价点集,各设计点对应着不同的设防水平;第二步在目标函数中综合考虑初始造价和未来若干年震害损失期望,求得最优设防水平及与其对应的一个最优设计方案。
Literature [1] and [2] pointed out that the objective function and constraint function of structural optimization design contain a large amount of fuzzy information, and the concept of fuzzy structural optimization design and the physical quantity (structure reaction and size) are proposed under the fuzzy allowable range. Α-level cutoff solution. This paper further proposes a method for the fuzzy optimal design of seismic structures. For this reason, the fuzzy prediction intensity, fuzzy response spectrum, and fuzzy response of the structure are defined. The fuzzy programming solution with generalized fuzzy constraints (including the fuzzy constraint function and its fuzzy allowable range) is given. The α-level cut-off solution used in [1] and [2] is its special case. The basis of this solution is to give the concept of the degree of satisfaction of the fuzzy constraint function to its allowed range of fuzzy values, and use it to convert the problem into a series of non-fuzzy plans, so as to obtain a sequence of the best, which is to solve the fuzzy plan. Foundation. In the optimal design of seismic structure, the first step is to use the above method to obtain the minimum set of structural cost points. Each design point corresponds to a different level of fortification; the second step considers the initial cost and the expected loss of future earthquake damage in the objective function. , Obtain the optimal level of defense and an optimal design scheme corresponding to it.