No abstract

WMA is a new technology, which is based on reduced temperature for mixing, and compaction of asphalt mixture, like any pavement material, testing the compatibility of this technology with domestically obtainable material is essential. The objective of the current research is to assist Iraqi establishments in addressing the issues related to resistance to rutting when adopting this technology. An intensive study on the performance of WMA mixtures with local materials was carried out. Job mix formulas with 12.5 mm and 25 mm aggregate size were chosen for HMA and WMA. One WMA technology was used which is an organic additive; two additives were used Asphaltan A® and Asphaltan B®. All the mixture types are testes and compared with each other. The rutting sensitivity of the mixtures is evaluated using Wheel Track test. From the results, for surface mixtures, rut depth is directly proportional to WMA additive content. For base mixtures, more Asphaltan A® leads to more rut depth, but more Asphaltan B® leads to less rut depth. Permanent deformation results of all mixtures, WMA and HMA mixtures are within the acceptable criteria.

Warm additives had wide popularity in recent years due to saving in energy and lowering emissions dealt with asphalt mixture production. Warm Mix Asphalt (WMA) is produced by using foaming technology or reducing -viscosity additives of binder to enhance the rheological properties. In this study, organic-based additives (Asphaltan A and Asphaltan B) are used to investigate their effect to minimize the viscosity and lower the temperature of asphalt mixture production. Bitumen is mixed with three doses of each additive: 1, 2, and 3% of its weight. The binder viscosity was measured by rotational viscometer with and without the additives at three different temperatures. The study showed that the organic additives have a positive impact on the behavior of the binder in terms of viscosity reduction and made enhancements in terms of bitumen properties. This result could be useful in the reduction of production temperature and quantity of odour emissions.