An Overview of Warm Mix Asphalt Paving Technologies

摘要

The asphalt paving industry is constantly exploring technological improvements that will enhance thernmaterial’s performance, increase construction efficiency, conserve resources, and advance environmentalrnstewardship. Current and impending regulations on emissions and energy conservation are makingrnattractive the reduction in asphalt mix production temperature. Warm Mix Asphalt (WMA) is a means tornthis end and several systems have been developed including: foaming, emulsions, additives, syntheticrnbinders and others. Warm mix asphalt is produced at temperatures 20 to 40oC lower than Hot Mix Asphaltrn(HMA).rnThe immediate benefit of lower temperatures is the reduction in energy consumption, greenhouse gasrnemissions, fumes, and odours generated at the plant and the paving site. The technical benefits arernsubstantial, including reduction of short term binder hardening, reduction of mixture tenderness, possiblernincrease of percentage of reclaimed asphalt pavement in new asphalt pavement mixes, and possiblernextension of the construction season.rnThis paper presents an overview of the current warm mix asphalt state-of-practice. A review of the variousrnwarm mix asphalt systems is provided. Findings of various studies concerning the observed and measuredrnfield performance and the environmental benefits in terms of energy conservation and reduced greenhouserngas emissions are also detailed.