In this paper, the authors continue investigating the applicability of Coral Reef Rock (C・R・R・), which is a sort of limestone produced in the Ryukyu Islands, to the base course of airport pavements.
　It was found that, as C.R.R. has not only a large corrected CBR but also some unconfined compressive strength, it is a useful material for the base course. The
latter characteristic, however, cannot be expected when C.R.R. is soaked.
　On the other hand, when C.R.R. is stabilized with cement, various of its characteristics are improved, e.g. strength, resistance to deformation, water-resistance and anti-fatigue.
　Stress and strain in the base course of asphalt pavements are then examined with an elastic theory. The results obtained are that two or three percent cement is sufficient for the purpose, and some layer equivalencies can be realized.