路用粗集料的三维形态表征及加工工艺影响分析

为定量分析路用粗集料的形状特征，采用高精度三维扫描仪获取集料表面的特征点阵，建立粗集料颗粒的实体模型；对集料二维与三维形态指标进行分析，探讨各指标的适用性；分析不同加工工艺对集料形态的影响。结果表明：不同视角下的集料轮廓周长和投影面积的差异较大，与集料扁平率指标密切相关，集料越接近针片状，二维轮廓的代表性越差；球度指标能够较好地表征集料三维粒型，集料越接近立方体状态，其球度值越大；椭球度指标可以较好地表征集料的棱角特性，棱角性越差，相应的椭球度值越大；反击破碎加工的集料球度偏低，棱角性较好；整形破碎加工的集料球度最优，但棱角性偏低；结合实际的需求，可以选择不同加工工艺组合掺配的形式，获得粒型与棱角性较均衡的集料成品。

Analysis of Three-dimensional Morphological Characterization of Road Coarse Aggregate and Influence of Processing Technology

In order to quantitatively analyze the shape characteristics of road coarse aggregate, a high precision 3D scanner was used to obtain the characteristic lattice of aggregate surface, and the solid model of coarse aggregate particles was established. The two-dimensional and three-dimensional morphological indexes of aggregate were analyzed and the applicability of each index was discussed. The influence of different processing techniques on aggregate morphology was analyzed. The results show that the circumference and area of the contour vary greatly under different viewing angles, which are closely related to the aggregate flatness ratio. The closer the aggregate is to the needle shape, the worse the representation of the two-dimensional contour. The sphericity index can better characterize the three-dimensional shape of the aggregate. The closer the aggregate is to the cube state, the larger its sphericity value is. The ellipsoid index calculated can be used to describe the angular characteristics of aggregates. As the angular properties become worse, the corresponding value of the ellipsoid increases. The sphericity of the aggregate processed by counter-breaking is low and the angularity is better; the sphericity of the aggregate processed by the shaping process is the best, but the angularity is relatively low. According to the actual demand, different processing technology combinations can be selected to obtain the aggregate products with more balanced grain shape and angularity.