桥梁方案多层多目标模糊优选模型及其应用

Application of multi-levels and multi-objectives fuzzy optimization model of bridge type selection

在桥梁概念设计阶段,关键是要选择出合理的桥型.在选择过程中需要考虑众多因素,这些因素不仅包括定量因素,而且还包括定性因素,因此桥梁方案优选是一个多目标、半结构性模糊决策问题.为了协调因素之间的复杂关系,提出了桥梁方案多目标模糊决策模型,将众多因素分层考虑,并应用模糊定权的方法来确定因素的权重,这一方法克服了目标函数中用线性评判指标来处理高度非线性多目标问题与确定权重问题的不足.应用实例表明,该模型理论严谨,物理意义明晰,计算方法简洁.

In the process of concept design of bridge, it is necessary to select the best from feasible alternatives through comparison. The criterion set, used to evaluate and select the satisfying alternative, consists of many qualitative and quantitative factors. Therefore, the selection is a problem of multi - criteria and semi - structural decision proceeding. The multi - levels and multi - objectives fuzzy optimization model of bridge type selection is applied to solve the complex relationship between factors. The factors are divided into several levels. Fuzzy method is adoptal to calculate the weight vector, which can overcome the limitation of linear method. A case study is given to show the efficiency and robustness of the new framework and methodology.