Performance of Half Warm Rolled Asphalt mixtures

One of the major problems that have plagued cold Bitumen Emulsion Mixtures (BEMs) since their introduction is high air voids. Therefore, this research will focus on this property and the attempts that have been applied to decrease the air voids of the produced new mixtures will be explained. In this connection, microwave heating has several advantages in comparison with the conventional heating method such as: it is volumetric heating, which represents an energy-saving point, and promotes rapid curing, which might enhance productivity. Therefore, a novel Half-Warm Rolled Asphalt (HWRA) has been produced by means of a pre-compaction microwave heating method. Consequently, Cold Rolled Asphalt (CRA) mixtures containing Ternary Blended Filler (TBF-2) have been mixed and then microwave heating, with 2450 MHz frequency and 300 W power, was applied in different durations in the pre-compaction method. The optimum microwave conditioning time was indicated in terms of stiffness modulus, air voids content and temperature which was 3 min microwave conditioning was chosen as the air voids decreased from 10.1% to 7.3%, the stiffness modulus decreased slightly and within an acceptable range and, finally, the temperature was in the moderate range (69 degrees C). The mechanical properties of HWRA have been investigated in terms of stiffness modulus, creep performance, fatigue life and fatigue fracture while water sensitivity and Long Term Oven Aging (LTOA) were conducted to investigate its durability. Generally, the performance in terms of mechanical properties and durability is promising due to high early stiffness modulus, long fatigue life and high Stiffness Modulus Ratio (SMR) in comparison with the control CRA and conventional hot asphalt mixtures. Crown Copyright (C) 2017 Published by Elsevier Ltd. All rights reserved.