Trr No. 1323 Materials And Construction, pp. 94-111

Moisture damage is a major problem for asphalt pavements constructed throughout much of the United States, as well as other areas in the world. A number of test methods and procedures have been developed to evaluate the moisture damage potential of asphalt-aggregate mixtures; however, these different test methods and variations do not yield the same results. A study of the relationships among various moisture damage test values for a range of mixtures using different antistripping additives compared two basic moisture damage test methods, that is, the wet-dry indirect tensile test (the Lottman test) and the boiling test. A number of variations of the wet-dry indirect tensile test were also compared. On the basis of the results of the test program, the moisture susceptibility test methods are ranked in the decreasing order of severity : (a) original Lottman method, (b) modified Lottman method, and (c) Tunnicliff-Root method. Correlations have been obtained between the moisture damage test values of the modified Lottman method and the other test methods. The relationships between the boiling test results and the wet-dry indirect tensile strength ratio values have also been established.