Published Paper Details:

Moisture-induced damage is one the major causes of deterioration of asphalt pavements and extensive research has been conducted on this topic. Theoretical and experimental results have led the researchers to believe that moisture-induced damages are caused mainly by the generation of pore water pressure in asphalt mixtures when traffic passes over a pavement. The Moisture Induced Sensitivity Tester (MIST) has been recently developed to simulate the phenomenon of repeated pore pressure generation and deterioration in the laboratory. The objective of this study was to evaluate moisture-induced damage in asphalt mixes, with the use of MIST, pre and post testing, and analysis of data. The MIST was used to condition Hot Mix Asphalt (HMA) samples that were compacted from five mixes, with different types of aggregates and asphalt binder. A modified Dynamic modulus test in Indirect Tensile Mode was used for the determination of damage. A layered elastic model, along with a fatigue-cracking criterion, was utilized to assess the total impact on the pavement lives. Monte Carlo analysis was conducted to determine the distribution of number of repetitions to failure of pavements that are subjected to moisture damage. The major conclusions are that most of the mixes are likely to experience a reduction in their life due to the effect of moisture and that the Micro-Deval and the fine aggregate absorption test results can be related to such damage. A composite factor, consisting of both of these test results, is recommended for regular use by the DOT to screen mixes with high moisture damage potential.