沥青混合料均匀性及其对路用性能影响研究

Homogeneity of Internal Structure of Asphalt Mixtures and Its Influence on Pavement Performance

为了准确评价沥青混合料内部分布均匀性,同时建立混合料均匀性与路用性能间的联系,首先,借助数字图像处理技术识别沥青混合料内部结构,提出了沥青混合料均匀性评价参数。对5种不同类型沥青混合料的均匀性和路用性能进行测试,并对二者之间的相互关系展开分析。试验结果表明:描述集料分布均匀程度的参数K可有效评价沥青混合料内部均匀性;虽然混合料内部分布均匀性与高温稳定性、低温抗裂性及水稳定性间不存在直接联系,但与表征各性能的评价参数变异性间的相关性较好,满足“内部分布越为均匀的混合料,对应的路用性能评价参数变异性越小”的规律。控制沥青路面性能变异性的关键之一即是从源头上对沥青混合料的均匀性进行控制。

In order to evaluate the internal distribution homogeneity of asphalt mixture accurately,and establish the relationship between the mixture homogeneity and pavement performance,firstly,The internal structure of asphalt mixture was identified based on digital image processing technique.Based on the above foundation,the evaluation index of mixture homogeneity was proposed.The homogeneity and pavement performance of five different asphalt mixtures were studied by laboratory tests,and the relationship between the homogeneity parameter and pavement performance of the asphalt mixture studied was established.The results suggest that the evaluation index(i.e.K),which describes the homogeneity of aggregate distribution,can evaluate the asphalt mixture homogeneity effectively.The homogeneity of asphalt mixture has no direct relationship with the high temperature stability,low temperature crack resistance and water stability,but has a good correlation with the variability of performance evaluation indices,satisfying the rule that"the better the homogeneity of asphalt mixture,the smaller the variability of corresponding pavement performance evaluation index".One of the keys to control the performance variability of asphalt pavement is to control the asphalt mixture homogeneity from the source.