灰色聚类法在再生混凝土粗骨料质量等级评价中的应用

基于灰色聚类评估理论,提出了利用多项参数综合评价再生混凝土粗骨料质量等级的方案.方案依据中国《混凝土用再生粗骨料标准》选取了表观密度、空隙率、坚固性、压碎指标、微粉含量、泥块含量、吸水率等7项参数作为综合评价指标,采用相似权法确定各指标的客观权重,根据评价指标等级赋值区间的特点,将质量等级划分为4个灰类等级;利用白化权函数构建了评价模型,通过对灰色聚类系数的计算,得出再生混凝土粗骨料质量等级的评价结果;最后通过实例分析检验了该评价方案的实用性.

Application of Grey Clustering Method for Quality Grade Estimate of Recycled Concrete Coarse Aggregate

A comprehensive estimate scheme employed multiple parameters is proposed for quality grade of recycled concrete coarse aggregate based on grey clustering theory. In the scheme, seven parameters are selected as comprehensive evaluation indices according to Recycled Coarse Aggregate for Concrete of China. The parameters are apparent density, porosity, sturdiness, crushing index, micro-mist content, silt content and water absorption respectively. Secondly, weighted similarity method is adopted to determine the objective weight, and divide the quality grade into four grey ranks according to characteristics of grade assignment interval of the indices. Then, whitening weight function is employed to make an estimate model, by which the quality grade estimate result of recycled concrete coarse aggregate can be achieved through compute of grey clustering coefficients. Finally, a case study is adopted to verify the practicability of the proposed scheme.