The National Road Research Alliance (NRRA) is hosting “Developing Best Practices for Rehabilitation of Concrete with Hot Mix Asphalt (HMA) Overlays Related to Density and Reflective Cracking” on October 19 at 10 a.m. CST, presented by by Eshan Dave and Katie Haslett, University of New Hampshire.
The NRRA’s monthly seminar highlights research topics that will make an impact on the work done here in the state of Minnesota and around the country.
Project Summary
Asphalt overlays are commonly used to rehabilitate deteriorated PCC pavements; however, mechanically or thermally-driven movements at joints and cracks in the underlying pavement usually lead to the development of reflective cracks in the overlay. The formation and propagation of reflection cracking is controlled by the mechanical properties of the asphalt and the condition of the overlaid pavement. Current state of practice for asphalt overlay design is policy oriented and lacking engineered design approach. There is need for establishing state of practice in design of overlays as well as for assessment of PCC pavement condition and recommending improvements to existing pavement prior to overlay construction. Objective of the proposed study is to develop a simple decision tree based tool for selecting suitable asphalt mixtures and overlay designs to prolong overlay lives by lowering reflective cracking and improving in-situ density. This research will leverage current NRRA effort of constructing, instrumenting and monitoring twelve MnROAD test sections, laboratory performance tests on asphalt mixtures from the test sections, and past field performance data. Proposed tool will incorporate field performance data, performance modelling, and life cycle cost analysis to develop best practices for rehabilitation of PCC with asphalt overlays.

Visit the MnROAD website for webinar connection information.