Highly permeable asphalt mixtures are prone to moisture damage leading to reduction in pavement service life. This study correlates dense-graded asphalt mixture’s air voids with its permeability. As permeability initiates due to significant interconnectivity of air voids, the relation between total air voids (TAVs) and connected air voids (CAVs) requires a critical review. Permeability of laboratory-compacted asphalt specimens was measured in the laboratory using four different permeameters. Conventional and Baily methods were utilized to develop aggregate gradations for asphalt mixtures. Different testing techniques were also used to ascertain the amount of CAVs, as aggregate gradation affects the airvoids significantly. An equation, based upon Darcy’s law, while assuming equilibrium of inflow/outflow of water to and from asphalt sample was proposed to determine the CAVs in the asphalt mix. The digital images of asphalt specimens were captured, and digital computed tomography (CT) technique was employed using ImageJ software for validation of the CAVs estimated from the relationship. It was observed that air voids, especially CAVs, and type of aggregate gradation have significant effects on permeability of asphalt mixture. The Baily modified mixes exhibited lower permeability. The permeability also increased with an increase in nominal maximum aggregate size. The interconnected pores, determined with the help of digital CT technique, validate the values of air voids estimated from the proposed relationship.

高渗透性的沥青混合料容易受到湿气的损害，从而导致路面使用寿命的缩短。这项研究将稠密等级的沥青混合料的气孔与其渗透率相关联。由于渗透性是由于气孔之间的显着互连而引发的，因此总气孔（TAV）与连通气孔（CAV）之间的关系需要进行严格的审查。在实验室中使用四种不同的渗透仪测量了实验室压实的沥青样品的渗透率。常规方法和Baily方法用于开发沥青混合料的骨料级配。由于聚集体的灰度会显着影响气孔，因此还使用了不同的测试技术来确定CAV的数量。根据达西定律的方程，同时假设水进出沥青样品的进/出平衡是确定沥青混合料中的CAVs。捕获沥青标本的数字图像，并使用ImageJ软件使用数字计算机断层扫描（CT）技术验证从该关系估计的CAV。观察到，空隙（尤其是CAV）和骨料级配的类型对沥青混合料的渗透性有显着影响。经Baily改性的混合物表现出较低的渗透性。渗透率也随着标称最大骨料尺寸的增加而增加。借助数字CT技术确定的相互连接的孔可验证根据建议关系估算的气孔值。捕获沥青标本的数字图像，并使用ImageJ软件使用数字计算机断层扫描（CT）技术验证从该关系估计的CAV。观察到，空隙（尤其是CAV）和骨料级配的类型对沥青混合料的渗透性有显着影响。经Baily改性的混合物表现出较低的渗透性。渗透率也随着标称最大骨料尺寸的增加而增加。借助数字CT技术确定的相互连接的孔可验证根据建议关系估算的气孔值。捕获沥青标本的数字图像，并使用ImageJ软件使用数字计算机断层扫描（CT）技术验证从该关系估计的CAV。观察到，空隙（尤其是CAV）和骨料级配的类型对沥青混合料的渗透性有显着影响。经Baily改性的混合物表现出较低的渗透性。渗透率也随着标称最大骨料尺寸的增加而增加。借助数字CT技术确定的相互连接的孔可验证根据建议关系估算的气孔值。骨料级配的类型和类型对沥青混合料的渗透性有显着影响。经Baily改性的混合物表现出较低的渗透性。渗透率也随着标称最大骨料尺寸的增加而增加。借助数字CT技术确定的相互连接的孔可验证根据建议关系估算的气孔值。骨料级配的类型和类型对沥青混合料的渗透性有显着影响。经Baily改性的混合物表现出较低的渗透性。渗透率也随着标称最大骨料尺寸的增加而增加。借助数字CT技术确定的相互连接的孔可验证根据建议关系估算的气孔值。