基于油石分离的再生集料颗粒形态多尺度变化

马川义¹，闫显亮²，吕鑫³，张吉哲³

1.山东高速集团，山东 济南  250098；2.山东省交通规划设计院集团有限公司，山东 济南  250098;

3.山东大学 齐鲁交通学院，山东 济南  250100

摘要：为研究废旧沥青混合料（recycle asphalt pavement，RAP）再生工艺对集料颗粒形态特征的影响，采用油石分离处置技术制备再生集料，建立考虑再生集料颗粒宏观-细观-微观的多尺度评价指标体系，结合三维扫描仪和集料图像测量系统测量新集料、未处置RAP和再生集料颗粒的球度、针片状指数、梯度棱角性和纹理指数等4个形态评价指标，对比分析3种集料颗粒的形态特征与多尺度变化规律。结果表明：相比于新集料颗粒和未处置RAP颗粒，再生集料颗粒的形态特征在宏观尺度上的指标参数变化不大，在微观-细观尺度上的指标变化较大，梯度棱角性平均减小12.5%，纹理指数平均增大14.0%，3种集料的4个形态指标均符合正态分布。相比于未处置RAP颗粒，再生集料颗粒的球度、梯度棱角性和纹理指数的标准差均明显变小，表明油石分离处置技术对改善再生集料颗粒的宏观-微观-细观形态特征的变异性有积极作用。对RAP进行高掺量再生利用时，应考虑再生集料颗粒的梯度棱角性和纹理指数与混合料路用性能的关联关系。

关键词：油石分离；再生集料；多尺度评价；颗粒形态；球度；梯度棱角性；纹理指数

Multi-scale variation of recycled aggregate particle morphology

based on oilstone separation

MA Chuanyi¹, YAN Xianliang²，LÜ Xin³, ZHANG Jizhe³

1. Shandong Hi-Speed Group, Jinan 250098, China;

2.Shandong Provicial Communication Planning and Design Institute Group Co., Ltd., Jinan 250098, China;

3. School of Qilu Transportation, Shandong University, Jinan 250100, China

Abstract:In order to study the influence of recycled asphalt pavement (RAP) regeneration process on the morphology characteristics of aggregate particles, the recycled aggregate is prepared by oil stone separation and disposal technology, and a multi-scale evaluation index system considering macro-mesomicro scale of recycled aggregate particles is established. Combined with the three-dimensional scanner and aggregate image measurement system(AIMS) to measure the sphericity, needle-like index, gradient angularity and texture index of new aggregate, untreated RAP and recycled aggregate. The morphological characteristics and multi-scale variation of three kinds of aggregate particles are compared and analyzed. The results show that, compared with the new aggregate and untreated RAP particles, the morphological characteristics of recycled aggregate particles do not change much at the macro scale, but change greatly at the micro-meso scale. The gradient angularity decreases by 12.5% on average, and the texture index increases by 14.1% on average. The four morphological indexes of the three aggregates accord with normal distribution. Compared with untreated RAP particles, the standard deviation of sphericity, gradient angularity and texture index of recycled aggregate are significantly smaller.It shows that the oil stone separation and treatment technology has a positive effect on improving the variability of macro-micro-microscopic morphological characteristics of recycled aggregate particles. When recycling RAP with high dosage, the association between the gradient angularity and texture index of recycled aggregate particles and the pavement performance of the mixture should be considered.

Keywords:oil stone separation ; recycled aggregate; multi-scale evaluation; particle morphology; sphericity; gradient angularity; texture index