fatigue behavior of warm mix asphalt vs. hot mix asphalt

by raising the costs of energy and crude oil, need to reduce costs is very vital. warm-mix asphalt (wma) technology allows decreasing the product temperature at which the material is mixed and placed on the road. reduction of 20 to 50 degrees centigrade has been documented. the reduction in energy consumption is the most obvious benefit of wma and consequently, reducing the production of co₂ and other greenhouse gases. in addition, engineering benefits include improving working conditions for production and paving workers due to reduced fumes, emissions and odors, ability to haul longer distances to pave at lower temperature, and allowing longer paving season. all in all, warm mix asphalt is an appropriate option when it is important to reduce the cost of asphalt production.the long-term performance of pavement is associated with various factors such as pavement structure, materials, traffic loading, and environmental conditions. this study explores the utilization of the conventional fatigue analysis approach (four-point bending beam fatigue testing) to investigate the fatigue life of the wma. the fatigue beams were made with two dense gradation with different nominal aggregate size, two wma additives (rheofalt and sasobit), and tested at 25 °c. a total of six mixtures were performed and 24 fatigue beams were tested in this study. the test results indicated that not only wma mixture reduced the mixing and compaction temperatures but also effectively extended the long-term performance of pavement when compared with conventional asphalt pavement.