基于改进灰熵关联分析的混合型再生粗骨料评价指标及分级研究

灰熵关联分析中分辨系数的确定是制约分析结果的关键因素。本文首先推导出了分辨系数的计算公式,在此基础上,通过室内配制混合型再生粗骨料,结合粗骨料路用技术要求,重点探究了废弃砖块对混合型再生粗骨料物理性质的影响;采用室内无侧限抗压强度试验分析了混合型再生粗骨料对水泥稳定碎石力学性能的影响;运用灰熵分析理论对混合型再生粗骨料性能指标与无侧限抗压强度进行关联性分析;通过非线性数据拟合的方法结合交通荷载等级和公路等级,确定出混合型再生粗骨料在基层中的适用范围;并对混合型再生粗骨料进行分级。结果表明:分辨系数取值不固定,在本文中最大值可取为1.000,最小值可取为0.141;混合型再生粗骨料替代石灰岩集料不超过20%(质量分数),且砖块在混合型再生粗骨料中的比例与交通荷载等级相关,最大值不宜超过40%(质量分数);经灰熵关联分析可把吸水率和压碎值作为混合型再生粗骨料分级指标,并将混合型再生粗骨料在道路工程中的应用等级分为三类。

Evaluation Index and Classification of Mixed Recycled Coarse Aggregate Based on Improved Grey Entropy Correlation Analysis

In grey entropy correlation analysis, the determination of resolution coefficient is the key factor that restricts the analysis result. In this paper, the formula of resolution coefficient was deduced firstly. On this basis, the mixed recycled coarse aggregate was prepared through indoor preparation, and the influence of waste brick on the physical properties of mixed recycled coarse aggregate was studied by the road technical requirements of coarse aggregate. The influence of mixed recycled coarse aggregate on the mechanical properties of cement stabilized macadam was analyzed by the unconfined compressive strength test, and the relationship between the performance index of mixed recycled coarse aggregate and the unconfined compressive strength was analyzed by the grey entropy analysis theory. Through the method of nonlinear data fitting combined with the traffic load grade and the highway grade, the applicable range and the classification of the mixed recycled coarse aggregate were determined in the road engineering base. The results show that the value of resolution coefficient is not fixed, which the maximum and minimum value is 1.000 and 0.141, respectively. The amount of mixture recycled coarse aggregate replacing limestone aggregate does not exceed 20%(mass fraction). Moreover, the proportion of bricks in the mixed recycled coarse aggregate is related to the traffic load grade, and its value could not exceed 40%(mass fraction). Through the grey entropy correlation analysis, the water absorption rate and crushing value are used as grade indexes of the mixed recycled coarse aggregate, of which the application grades are divided into three categories in road engineering.