A real-time system for prediction cooling within the asphalt layer to support rolling operations

During the hot-mix asphalt (HMA) paving process roller operators generally rely on personal experience and have little information about the in-asphalt temperature [1] . Information about temperature, however, is important for the final quality of the pavement. HMA mixes need to be compacted within a certain temperature window. Too hot may create corrugations. Too cold may create damage [21]. The introduction of the Warm Mix Asphalt, for reasons of sustainability, affects the compaction practice directly. The operational choices of the roller operator become more critical. Until now most operators assessed temperature on look and feel. A more method based approach is needed. Because the in-asphalt temperature is not easy to predict and measure, reliable real-time information system is necessary. This paper describes the development and first test of such a system. Continuous surface and in-asphalt temperature measurements are the first step in monitoring cooling of the asphalt layer. When presented in a comprehensible fashion, roller operators can use this information to develop more pro-active compaction strategies. The developed automated temperature unit (ATU) provides real-time surface- and inasphalt temperature information to roller operators. Implemented system displays measured and predicted asphalt temperature changes as well as the time left before the mix will cool down to the certain temperature. Temperaturerelated information might assist machine operators in making decisions when to start and when to stop rolling, as it is indicated by the preliminary results. Analysis of recorded temperature data can help to improve paving practices.