The purpose of this paper is to obtain the pore distribution of asphalt mixture accurately by nondestructive technology. Specimens prepared with four gradations of asphalt mixtures were scanned using X-ray computed tomography (CT) which was used to measure air void sizes at different depths within specimens. The air void distributions of obtained CT images were analyzed using ring blocking segmentation combining Otsu’s method, which provided an accurate estimate of air voids in asphalt mixtures. The image processing results showed that air void distribution was not uniform in the specimens; higher air void concentrations were found at the top and bottom of the specimen, and lower, in the rest of the sample depth. The air void sizes of SUP13 and AC13 are mainly distributed between 0.15 to 0.2 mm, while PA13 and SMA13 are 0.4 to 0.65 mm and 0.4 to 0.7 mm, respectively. It is believed that the CT pictures processed by the ring blocking segmentation combining Otsu’s method is feasible and rational to capture the air voids size and content of asphalt mixtures.+

中文翻译：

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X射线计算机断层扫描和大津法研究沥青混合料空隙结构的研究

本文的目的是通过无损技术准确地获得沥青混合料的孔分布。使用X射线计算机断层扫描（CT）扫描由四个等级的沥青混合料制备的样品，该X射线计算机断层扫描用于测量样品中不同深度的气孔尺寸。使用Otsu方法结合环阻断分割法对获得的CT图像的气孔分布进行了分析，该方法可以准确估算沥青混合料中的气孔。图像处理结果表明，试样中的气孔分布不均匀。在样品的顶部和底部发现较高的空气空隙浓度，在其余样品深度中发现较低的空气空隙浓度。SUP13和AC13的气孔尺寸主要分布在0.15至0.2 mm之间，而PA13和SMA13的气孔尺寸为0.4至0.65 mm和0.4至0。分别为7毫米。相信通过Otsu方法结合环阻断分割处理的CT图像是可行和合理的，以捕获气孔的大小和沥青混合料的含量。