基于模糊可拓层次分析法-聚类的桥梁安全评价分析

Analysis of bridge safety evaluation based on fuzzy extension analytic hierarchy process-clustering

桥梁的结构安全评价指标具有多因素、多层次、高难度的特点,采用模糊可拓层次分析-模糊聚类相结合的方法,以武汉白沙洲长江大桥为例,首先通过专家对结构指标的重要程度用可拓区间判断矩阵得到各指标的权重,建立桥梁综合评估模型,进而得到桥梁的评价结果。结合最大树法将桥梁指标进行评判,利用平移极差变化法进行标准化并选定平方欧式距离公式构造模糊矩阵,选取不同的阈值再进行剪枝,得到确定风险因素的分类,最后用高斯混合模型得到最终的散点图和三维拟合高斯模型进行聚类分析,两种方法结合较好地对桥梁的安全性进行了评估,符合桥梁实际情况,结果表示桥梁安全性较好。

The structural safety evaluation index of the bridge has the characteristics of multi-factor,multi-level and high difficulty.The method of combining fuzzy extensibility level analysis and fuzzy clustering was adopted.Taking the Yangtze river bridge located in Wuhan Baishazhou as an example,the weight of each index was obtained by experts using the extensible interval judgment matrix to determine the importance of the structural index,and a comprehensive evaluation model of the bridge was established.Then the evaluation results of the bridge were obtained.Combined with the maximum tree method to evaluate the bridge index,the translation range change method was used to standardize and select the squared Euclidean distance formula to construct a fuzzy matrix.Different thresholds were selected and then pruned to obtain the classification of risk factors,and finally the Gaussian mixture model was used to obtain the final scatter plot and three-dimensional fitted Gaussian model for cluster analysis.The safety of the bridge were well evaluated by the two combined methods,which is in line with the actual situation of the bridge,and the results indicate that the bridge safety is fine.