two 15 penetration grade bitumens, two aggregate gradations (UK and French designs), varying binder and air void contents and different fillers. The results from the SATS test have been compared directly with those obtained on the same mixtures using the AASHTO T283 procedure. Both the SATS and AASHTO method have been able to rank the moisture conditioning performance of the different mixtures with the order of ranking being identical. The HMB mixtures containing the acidic aggregate (including low air void content and high binder content combinations) produced lower ratios of retained stiffness (and strength for AASHTO T283) compared to the basic aggregate mixtures as well as an acidic aggregate mixture including hydrated lime filler. However, the relative performance of the two tests (in terms of retained stiffness ratio) differed considerable for the moisture susceptible acidic aggregate mixtures with the retained stiffness values from the AASHTO T283 procedure being approximately double that of the SATS test at nominally the same saturation levels. The combined ageing / moisture conditioning SATS test can therefore be considered to be a more severe procedure compared to the accelerated water conditioning with freeze-thaw cycle AASHTO T283 method. In addition, the SATS test was the only procedure that was able to reproduce the 60% reduction in stiffness modulus found for the acidic aggregate HMB mixture in the field.
