沥青混合料压实过程三维骨架结构接触状态与稳定性评价  

Contacting Condition and Stability Evaluation of Three-Dimensional Skeleton of Asphalt Mixture during Compaction

作　　者：郑齐 闫寒 孙晓龙 龚湘兵 郑和琪 ZHENG Qi;YAN Han;SUN Xiaolong;GONG Xiangbing;ZHENG Heqi(Guangzhou Expressway Co.,Ltd.,Guangzhou Guangdong China 510500;School of Civil Engineering,Guangdong University of Technology,Guangzhou Guangdong China 510006;School of Traffic and Transportation Engineering,Changsha University of Science and Technology,Changsha Hunan China 410114)

机构地区：[1]广州市高速公路有限公司,广州510500 [2]广东工业大学土木与交通工程学院,广州510006 [3]长沙理工大学交通运输工程学院,长沙410114

出　　处：《广东公路交通》2022年第6期1-7,共7页Guangdong Highway Communications

基　　金：广东省基础与应用基础研究联合基金青年基金项目(2019A1515110348);广东省高校青年创新人才类项目(2018KQNCX067)。

摘　　要：传统的沥青路面压实质量评价多采用压实度为控制指标,忽视了细观尺度下粗集料颗粒接触与嵌挤状态的演变规律,难以对压实质量进行精准控制,进而无法对沥青路面的耐久性进行评估。采用压实过程分步式工业CT同步扫描技术,利用改进后的Otsu分割算法实现对沥青混合料粗集料、砂浆、空隙三相的分割,通过图片堆积实现沥青混合料的三维重构,结合最小包围盒算法获取粗集料的就位特性及几何信息,计算获取粗集料有效平均配位数。研究结果表明,Otsu分割算法适用于沥青混合料细观组分分割,有效平均配位数能够表征粗集料的接触状态。而且,无效配位数与集料尺寸有较大关系,集料尺寸越大,其产生“无效颗粒”的可能性就越小。随着压实次数的增加,各档集料的有效平均配位数均随之增加。通过对比流动次数的数据发现,有效平均配位数可作为压实过程沥青混合料骨架结构稳定性的评价指标。Traditional compaction evaluation has been based on the compaction degree, which ignores the contacting conditions and interlocks of coarse aggregates at mesoscale. The improved Otsu segmentation algorithm has been used to segment the coarse aggregate, mortar and void of asphalt mixture in this paper. The three-dimensional reconstruction of asphalt mixture has been realized by using image staking method, and the location characteristics and geometric information of coarse aggregate have been obtained by combining with the minimum bounding box(OBB) algorithm. Results have shown that improved Otsu segmentation algorithm is effective to conduct the image segmentation of different mesoscopic components and effective average coordination number is suitable to evaluate the contacting conditions of coarse aggregates. Moreover, the larger the aggregate size means that the smaller the possibility of producing invalid particles. With the increase of compaction times, the effective average coordination number of each grade of aggregate will increase. Being compared with the flow number, the effective average coordination number is effective to evaluate the stability of skeleton with different compaction number.

关 键 词：沥青混合料 细观结构 数字图像处理 骨架结构 压实过程 

分 类 号：U416.217[交通运输工程—道路与铁道工程]