A COMPARISON OF FREEZING AND THAWING DURABILITY OF NON-AIR ENTRAINED CONCRETE PAVERS UNDER ASTM C-67 AND ASTM C-666

ASTM C 936 currently evaluates the resistance to freezing and thawing of paving blocks by either historical performance in the field or by a n accelerated laboratory test found in ASTM C 67. Criticisms have been raised by both paver manufacturers and private agencies regarding the ability of this procedure to adequately simulate the exposure conditi ons to which block pavements may encounter. This paper attempts to add ress these concerns by comparing the performance of concrete pavers te sted under ASTM C 67 conditions to that of the most widely used freezi ng and thawing standard for concrete products, ASTM C 666. A compariso n of the test results revealed significant variation in the amount and rate of deterioration, and the mode of failure. Disparities were also observed the two tests regarding the minimum cement content and bulk properties necessary for adequate resistance within each freezing and thawing regimen. In addition, the strength and absorption properties o f frost resistant pavers were not in agreement with the requirements o f ASTM C 936. Based on the results of this study, the development of a new freezing and thawing procedure, devised specifically for concrete paving units, appears warranted.