Assessment of water sensitivity of asphalt rubber mixtures for wearing course

Abstract

To assess the water sensitivity of asphalt rubber mixtures an experimental study was carried out, in which different types of gap-graded mixtures applied in wearing courses were used. The experimental study compares the results obtained by the test method traditionally used in Portugal - the American army standard MIL-STD-620A – method 104 - with those obtained through the EN 12697-12:2008-method A. The application of the European standard leads to lower values of retained resistance than those obtained with the American army standard and al-lows for a better distinction of the behavior of different mixtures. This paper presents the main results achieved so far, and contributes for the achievement of reference values for water sensi-tivity of gap-graded asphalt rubber mixtures determined according to the European standard EN 12697-12:2008 - method A.