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Meteorological factors like air and dew point temperature and relative humidity levels influence a pavement surface's response to rapidly increasing air temperature combined with freezing conditions. This scenario can result in black ice. Black ice is dangerous due to its thinness and transparency. Understanding the conditions for black ice development benefits winter pavement maintenance by limiting chemical overuse and forming a basis for warning systems. However, limited experimental data on this weather scenario exists. A fully instrumented model column was built using soil and a concrete pavement slab obtained from the Dallas Fort Worth (DFW) airport. The column duplicated the airport pavement structure and subgrade. The system was placed in a freezer box and wrapped in insulation. The weather scenarios simulated historic airport weather involving freezing temperatures followed by rapid temperature increases and high relative humidity. After multiple baseline tests, two successfully replicated the rapid temperature increase scenario. The formation of frost on the pavement surface occurred 40 min after condensation developed combined with a surface temperature of −2°C and dew point temperatures above 0°C. The results of this study provide insight into frost development on pavement and is useful in implementing proactive winter pavement maintenance for black ice. [ABSTRACT FROM AUTHOR]

Meteorological and subsurface factors influence pavement's response to cold fronts. Prediction of pavement temperature, particularly icing, is important to winter pavement maintenance which relies on an estimated time for the formation of ice. However, the prediction development is limited by test data on pavement icing. A model column consisting of soil samples and a concrete pavement slab retrieved from the Dallas Fort Worth airport was used to replicate the airport pavement structure, including subgrade. The soil was classified using USCS, tested for optimum moisture content and compacted in lifts in the column. Thermistors and moisture sensors were placed at different depths. The pavement slab was fitted with temperature sensors throughout. The system was installed in a freezer box,wrapped in insulation and plastic. Three cold front scenarios were selected from observed airport weather data and simulated in the freezer box using varying rates of temperature decrease and precipitation. The formation of ice on a pavement surface was observed at 10–20 min after the start of precipitation. This time frame is not affected by the freezer box cooling rate. The icing time found from this study is useful for the development of prediction models for icing onpavements. [ABSTRACT FROM AUTHOR]