Study on Water Stability of Evotherm<sup>®</sup> Warm Asphalt Mixture

Abstract

AC-13C asphalt mixtures were mixing with 3% Evotherm® content and the optimal compaction temperature was determined according to test results of specimens formed at 4 different compaction temperatures by Marshall method. The general water stability tests and Hamburg wheel-tracking device (HWTD) were used to test the water stability of 4 kinds of asphalt mixtures, which were ordinary asphalt mixture, Evotherm® asphalt mixture without adding any anti-stripping agent, Evotherm® asphalt mixture adding liquid anti-stripping agent and Evotherm® asphalt mixture adding hydrated lime. Test results shows that the optimal compaction temperature is about 125°C; and compared to ordinary asphalt mixture, the long-term water stability of Evotherm® asphalt mixture is obviously poor caused by the lower compaction temperature; the addition of either liquid anti-stripping agent or hydrated lime improve the water stability to a great extent; comparatively speaking, addition of hydrated lime is the optimum measure to improve the water stability of Evotherm® warm mixture asphalt.