Optimized taconite-based pavement repair compound and deployment system

Project summary:

This project refined the Natural Resources Research Institute's (NRRI) patented taconite-based repair compound, explored equipment options, and field-tested/demonstrated a low-cost mechanized system that can efficiently mix and place the repair compound in larger quantities while minimizing or eliminating direct contact and hand mixing by maintenance personnel. The rigid, taconite mineral-based, all season rapid-setting repair compound contains neither petroleum nor portland cement. As such, its environmental footprint is much smaller than cold-mix or hot-mix asphalt products, mastic, and portland cement-based repair compounds. The refined and optimized formulation utilizes relatively low-cost and abundant mineral byproducts and co-products, and the mechanized deployment system makes use of relatively inexpensive commercially available (i.e., off-the-shelf) equipment, compared to single-bucket mixing. Larger-scale continuous mixing remains a challenge and is still under investigation. The expected economic benefits include cost savings for both raw materials and maintenance labor. In addition, the rapid-setting nature of the formulation combined with a mechanized deployment system would allow pavement and pothole repairs to be conducted faster and with moving traffic control, thereby avoiding lengthy traffic-disrupting lane closures. Key project outcomes are lower costs, better-quality and longer-lasting repairs, and improved productivity.