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Minnesota Department of Transportation

511 Travel Info

Road Research

Research Reports

Orange barrels on a highway

Asphalt Binder Modification: MnROAD Field Investigation of Polyphosphoric Acid Modified Asphalt

This MnROAD study built upon the findings of previous Federal Highway Administration research to Pavement truck rolling on pavementconduct a field trial assessing the performance of Polyphosphoric Acid (PPA) over a 5-year period. PPA has been used for 30 years to stiffen asphalt pavement. Recent research by the FHWA and MnROAD hope to establish mutual cost-effectiveness and asphalt strength to provide a better utilization method for PPA.

Work Plans

Reports and Publication

Presentations