ABSTRACT
Recently, the various types of cavities under the road pavement have been frequently occurred in the urban area of Seoul, Korea. These cavities cause the collapse and settlement in the pavement and have a bad influence on safety of driver. The objective of this study is to evaluate the effect of size and depth of cavities on the pavement failure using the accelerated pavement testing. Two rectangular shape of cavities were installed at depth of 0.3 and 0.7 m from the surface in the testbed. The cavities are made of ice with 0.5*0.5*0.3 m of dimension. The thickness of asphalt and base layer were 0.2 m and 0.3 m, respectively. An 80 kN of wheel loading was applied on pavement section with 10 km/h of speed. The permanent deformation was measured periodically at given number of repetitions. For cavity section of 0.7 m depth, the 30 mm of permanent deformation was measured at 90,000 load repetitions which is three times greater than intact section. In case of section with cavity at the depth 300 mm from the surface, about 900 mm of permanent deformation was measured at 32,000 load application which is twenty times higher than cavity section of 0.7 m depth.
