The strength, durability and workability of asphalt paving mixtures has changed significantly due to the
use of additives. Warm Mix Asphalt (WMA) is an example of such additives which lowers the
temperature of the asphalt mix between 30 to 120°F as compared to conventional HMA. A research study
was conducted to evaluate additives Evotherm M1, Kaoamin 14, Sasobit and Rediset in WMA. The
results showed that additives reduced the asphalt binder viscosity of 380 cP to an average of 295 cP at a
temperature of 135 °C and Sasobit also modified the Performance Grade from a PG 64-22 to PG 70-22.
Mixtures with the modified binders were evaluated for compaction, susceptibility to moisture and
susceptibility to permanent deformation. Compactability results indicated that the specimens were not
susceptible to temperature after been produced and compacted at a temperature of 285 °F and 240 °F,
respectively. Susceptibility to moisture results showed that Evotherm M1 with a TSR of 96.1% has less
probability to stripping. The Flow Number test showed that compacted mixtures subjected to a traffic
level between 10 and 30 MESAL are not susceptible to permanent deformation therefore, not affecting
the performance of WMA as compared to HMA.
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