Low Temperature Cracking in Asphalt Pavements
Low temperature cracking is the most prevalent distress found in asphalt pavements built in cold weather climates. As the temperature drops the restrained pavement tries to shrink. The tensile stresses build up to a critical point at which a crack is formed. Thermal cracks can be initiated by a single low temperature event or by multiple warming and cooling cycles and then propagated by further low temperatures or traffic loadings.
The current Superpave specification attempts to address this issue by specifying 
a limiting low temperature for asphalt binders. However, the first phase of this project made it clear that testing asphalt mixtures is necessary to accurately predict low temperature cracking performance in the field. Furthermore, the testing must include more sophisticated techniques based on fracture mechanics rather than the current practice of stiffness and strength testing.
Current Research Efforts
- DCT Sample Prep Video (Summer 2014)
- LTC Implementation (Fall 2014)
- Minnesota DCT Testing Update (Jan 2015)
Past Research Efforts
- LTC Pooled Fund Phase-II Project Page
- Phase-II Final Report (2012 PDF)
- LTC Pooled Fund Phase-I Project
- Phase-I Research Brief (2009 PDF)
- Phase-I Executive Summary (2007 PDF)
- Phase-I Final Report (2007 PDF)
Future Research Efforts
TBD
Products
Implementing LTC Spec in MN
Implementing LTC Spec in IA
Project Summary & Significant Contributions