In Minnesota the transition from winter to spring is normally accompanied by the formation of potholes and other distresses as streets and highways weaken and adjust to warmer conditions. At times the extent of this seasonal deterioration can be so vast that maintenance crews are required to give full-time attention to the problem. Patching often continues, or is repeated, as the seasons pass from spring to fall.
During winter and early spring agencies often use “cold mix” asphalt for patching, and eventually return to “hot mix” as soon as bituminous plants can be activated. The
effectiveness of these standard materials depends largely on the level of effort that patching crews can devote to site preparation and material placement.
In the spring of 2011, the cities of Bloomington and Minnetonka, Minnesota collaborated on a field investigation of the installation and field performance, of two “mastic” patching materials along with standard patches that were applied at the same time. The investigation was funded by the OPERA program and normal maintenance budgets. Mn/DOT Road Research assisted in documenting the installation and conducting autumn performance evaluations.
