Evaluating Warm Asphalt Technology as a Possible Tool for Resolving Longitudinal Joint Problems

摘要

This paper summarizes preliminary findings from an integrated laboratory and field study that is currently underway in the City of Hamilton to examine the impact of warm asphalt and how it can be used as a possible tool for examining longitudinal joint problems. It is a partnership between the City of Hamilton, the Centre for Pavement and Transportation Technology located at the University of Waterloo, and McAsphalt Industries. There are several reasons to consider reducing the temperature at which a hot mix is placed in the field. Lowering the mix temperatures could result in several construction and performance benefits including reduced aging of the asphalt binder, reduced fumes or odours, reduced tenderness of the mix during compaction and reduced draindown with coarse mixes. A longitudinal joint is the interface that exists between two Hot Mix Asphalt (HMA) lanes that are paved one after another. Premature failure of these longitudinal joints can vary from slight ravelling at the joint to complete erosion of the mix at the longitudinal joint leaving a large gap in the pavement. Overall, this paper shares some of the key findings from the initial laboratory and field evaluation. This includes Dynamic Modulus and Resilient Modulus results observed from the laboratory prepared samples. In addition, findings from the field evaluations, including longitudinal joint permeability testing and surface distress surveys are presented.