More than 600 cavities underneath the road have been recently discovered in the city of Seoul using ground penetrating radar testing. Various types of cavities will affect the settlement of pave-ment structures with time and traffic passage. The objective of this study is to simulate the full- scale road collapse due to the occurrence of cavity using accelerated pavement testing (APT). A cubic shape of cavi-ty was installed at depth of 0.3m from the surface in the testbed. The cavity was made of ice with 1m*1m*1m of dimension and the thicknesses of asphalt and base layer were 0.2m and 0.3m, respectively. An 80kN of APT wheel loading was applied on pavement section with 10km/h of speed. Strain gauges were also installed at the bottom of asphalt layer to measure the tensile strain at cavity and intact section. It is observed from this testing that the subbase material initially started to fall off from the bottom of as-phalt layer. After then, the cracks initiate at the bottom of asphalt layer with settlement of pavement sur-face. Finally, the width of crack increases with number of load application and the permanent deformation is found to be 130mm at 6,000 of load application. It is also found from strain measurements that the ten-sile strain values at cavity section are two times greater than those at intact section.
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