Experiences with Warm Mix Asphalt – A Contractors Perspective

摘要

During the past three years, Warm Mix Asphalt (WMA) technologies from European countries have entered the North American market. European experiences with WMA technologies have indicated that a significant reduction in mixture temperature, mixture viscosity, energy consumption and environmental emissions during asphalt mix production and placement can be achieved in comparison with traditional Hot Mix Asphalt (HMA). Based on North America experiences to date with these technologies, transportation agencies and HMA producers are unlikely to adopt WMA technologies solely for the reduction in manufacturing energy costs and environmental emissions, as these benefits do not cover the associated increase in investment and additive costs of WMA over HMA, even in the most expensive North American energy markets. This paper presents an evaluation of the economic, environmental and mixture performance factors in order to assess the sustainability of WMA in North America. The paper examines the benefits, risks, investment and material costs, and sustainability associated with the different WMA technologies and specifically the Double Barrel? Green process. Included is an mixture performance evaluation of WMA mixes containing Reclaimed Asphalt Pavement (RAP) and Manufactured Shingle Modifier (MSM?) produced with the Double Barrel? Green process during field trials in Vancouver, British Columbia.