Moisture-induced damage to asphalt concrete pavements, often attributable to stripping, is a recurrent problem because of the several variables involved. Many different tests are used to determine themoisture susceptibility of an asphalt mixture. Nevertheless, some are subjective and not suitable for evaluating individual aggregate components; whereas others have poor reproducibility, and no reasonable correlations with field performance can be obtained. At present many road test laboratories are using the texas boiling test and lottman's tensile strength ratio. Plancher et al. Have developed the freeze-thaw pedestal test, which is a simple laboratory test with a high degree of reproducibility. This test maximizes the effects of moisture at extreme temperatures and minimizes the effects of the mechanical properties of the mix (interlocking, density, gradation, etc.).Tests were conducted using different aggregates and types of bitumen: paving grade asphalt cement ac 70/100 and two types of asphalt emulsions--anionic slow-setting and cationic slow-setting. Results from these studies show the potential of this test in determining the susceptibility of cold and hot asphalt mixtures to moisture damage. This paper appears in transportation research record no. 1228, Asphalt mixtures and asphalt chemistry.
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