Abstract
In order to ensure the freezing and thawing resistance of extremely stiff consistency concrete such as roller compacted concrete pavement slab and instant stripping concrete blocks, the effect of air content and compaction void on durability factor were clarified in the case of increasing in water content and dosage of air entraining agent for a given unit cement content and increasing in sand percentage and compaction ratio for a given unit water content. And it was shown that the fine compaction voids were able to improve the freezing and thawing resistance and the void spacing factor including compaction void was larger than that of ordinary concrete with 60% of durability factor. Then, it was shown that the factor could be obtained safely by over 97% of compaction ratio on condition of over 2% of air content. Finally, the relationship between the freezing and thawing resistance index newly expressed by air content, water cement ratio and compaction ratio, and durability factor was shown as an experimental equation.