[01] Saad Issa Sarsam, Department of Civil Engineering, College of Engineering, University of Baghdad, Baghdad, Iraq. [02] Zainalabiden Nihad, Department of Civil Engineering, College of Engineering, University of Baghdad, Baghdad, Iraq.

One of the finest choices of green and sustainable paving materials in asphalt concrete paving operation is the Warm mix asphalt concrete. The lower temperatures implemented in the mixing, handling, and compaction of the mix gets in saving energy, cutting emissions and significant cuts in construction costs. The concept of the WMA is to produce mixture which have the same durability, performance and strength as that of traditional hot mix asphalt concrete HMA. As the result of decline in the temperature of WMA, it exhibits less aging of asphalt mixture. It is known that, asphalt oxidation lead to stiffen of the binder and may cause various pavement distresses. In this work, the temperature susceptibility of two types of warm mix have been compared with those of HMA. Cylindrical specimen of 63.5 mm in height and 101.6 mm in diameter have been prepared using medium curing cutback and cationic emulsion in case of warm mix and asphalt cement in case of hot mix. Specimens were tested for indirect tensile strength ITS at 5 and 20 °C. It was concluded that WMA are less susceptible to temperature than HMA. The temperature susceptibility at optimum asphalt content are (24, 17 and 19) kPa/°C for the HMA, WMA-emulsified asphalt and WMA-cutback asphalt respectively. WMA exhibit higher ITS at 25°C than HMA by 30.59% and 23.9% when using cutback asphalt and emulsified asphalt with WMA respectively, on the other hand, WMA exhibit higher ITS at 5°C than HMA by 11.77% and 4.14% when using cutback asphalt and emulsified asphalt with WMA respectively.

Warm Mix, Hot Mix, Temperature Susceptibility, Indirect Tensile Strength, Asphalt Concrete, Green Pavement

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