Recycled coarse aggregates, including crushed brick recycled coarse aggregate (CBRCA) and crushed concrete recycled coarse aggregate (CCRCA), are increasingly used as raw material in building materials. In fact, the morphological characteristics of recycled coarse aggregates take great effect on properties of materials. Therefore, this paper mainly investigates the morphological characteristics and physical properties of brick-concrete recycled coarse aggregate (BCRCA) composed of CBRCA and CCRCA. Morphological characteristics indexes of coarse aggregates including angularity, sphericity, texture and fractal dimension were described by digital image processing technique. The differences of morphological characteristic indexes among recycled coarse aggregates and natural crushed gravel coarse aggregate (NCGCA) were discussed. Results show that CBRCA has the highest void content, crushing index and water absorption among the four types of aggregates. Compared with NCGCA, recycled coarse aggregates have a higher angularity, lower sphericity and higher texture. The fractal dimension of recycled coarse aggregates is higher than NCGCA, indicating the complexity of shape of recycled coarse aggregates. Among the recycled coarse aggregates, CBRCA has the highest angularity and lowest sphericity, and CCRCA has the highest texture. The angularity and texture are significantly influenced by aggregate types. The sphericity and flatness ratio, as well as the angularity and texture have good positive correlation. The fractal dimension and elongation ratio, as well as the fractal dimension and sphericity have negative correlation. By testing two-dimensional indexes including fractal dimension and elongation ratio can easily reflect the morphological characteristics of coarse aggregates. When recycled coarse aggregates is used in building materials, the morphological characteristics should be carefully considered.

再生粗骨料，包括碎砖再生粗骨料（CBRCA）和碎混凝土再生粗骨料（CCRCA），越来越多地用作建筑材料的原材料。事实上，再生粗骨料的形态特征对材料的性能影响很大。因此，本文主要研究由CBRCA和CCRCA组成的砖混再生粗骨料(BCRCA)的形态特征和物理性能。采用数字图像处理技术描述粗骨料的棱角、球度、纹理和分形维数等形态特征指标。讨论了再生粗骨料与天然碎石粗骨料(NCGCA)形态特征指标的差异。结果表明，CBRCA在四种骨料中孔隙率、破碎指数和吸水率均最高。与NCGCA相比，再生粗骨料具有更高的棱角、更低的球形度和更高的质地。再生粗骨料的分形维数高于NCGCA，表明再生粗骨料形状的复杂性。在再生粗骨料中，CBRCA的棱角度最高，球度最低，CCRCA的质地最高。棱角和质地受骨料类型的显着影响。球度和平面度比，以及棱角和纹理具有良好的正相关。分形维数和伸长率，以及分形维数和球度呈负相关。通过检测分形维数和伸长率等二维指标，可以很容易地反映粗集料的形态特征。当再生粗骨料用于建筑材料时，应仔细考虑其形态特征。