Cracking of asphalt pavements in cold regions has always presented a problem, because it can directly affect pavement rideability and material behaviour and, therefore, service life. If left untreated, cracking will develop into more drastic distresses, such as spalling, potholes, deformation, and even structural failure. These distresses are irreversible and are a major factor in pavement surface roughness. A prime example is the transverse crack that, when left untreated, develops permanent and seasonal deformation in the form of lipping or cupping. Lipping is an upheaval, and cupping is a depression of the pavement profile at the transverse crack. The Ontario Ministry of Transportation has an ongoing preventive maintenance measure, a crack rout-and-seal program, to minimise the effects of cracking. The ministry also seeks to improve rout-and-seal methodology and discover sealant materials that perform better. This paper presents some up-to-date results from these investigations.
Abstract