Cold Bituminous Emulsion Research Articles

Investigating the raveling test for full-depth reclamation

Full-Depth Reclamation (FDR) is a sustainable method of building pavement structure compared to more traditional rehabilitation methods. Traffic is generally returned to an FDR project before a surface course is applied, as water in the FDR needs time to evaporate from the structure. This should not be done too quickly or raveling occurs. Currently, there is no test to quantify the timing of return to traffic. In this study, the “Raveling test of cold mixed bituminous emulsion samples” (ASTM D7196) was used to compare asphalt emulsion and asphalt foam FDR. Asphalt emulsion samples were cured at ambient and 40 °C temperatures, while asphalt foam samples were cured at ambient temperatures. Raveling test data was collected from 0 to 48 hours of curing, however, samples were often not able to withstand fifteen minutes of testing. Therefore, the “time lasted” (the time the raveling head loses contact with the surface of the sample) was recorded. In general, the asphalt emulsion samples that were cured in the oven at 40 °C had a longer time lasted and showed higher potential for determination of return to traffic. In addition, the asphalt emulsion samples had a longer time lasted than the asphalt foam samples at ambient temperatures.