Journal of the Korean Asphalt Institute ISSN:2234-0785(Print) 2635-9553(Online) 한국아스팔트학회지

In ths study, the characteristics of watertight asphalt concrete were analyzed to prolong the life of overlay over concrete pavement. It was shown that the air void content was grater than or equal to 1.0 percentage (%) in order to meet the minimum standard for dynamic stability. And the range to secure a stable dynamic stability level of 1,000 cycle/mm was found to be between 1.0 and 2.0%. Under the same dynamic stability level condition, it was possible to reduce air void content by 1.0% by using PG 76-22 binder compared with using to PG 64-22 binder. This will be a great advantage for the asphalt layer to provide more stable watertightness under the surface course. The APT test results showed that the average rut depth of watertight WC-1 (PG 64-22) was 3.1 mm and 1,5 times higher than watertight WC-1 (PG 76-22). When the dynamic stability was increased by 5.8 times, the rut depth of APT test tends to decrease by 1.5 times. The results of the follow-up investigation of the test construction showed that watertight WC-1 (PG 64-22) with was 4.5mm in rut depth, which is 1.2 times higher in depth than watertight WC-1 (PG 76-22).