Non-Polishing Values for Carbonate Aggregates Research Underway

The Virginia Transportation Research Council has commenced research centered around developing polishing standards for carbonic aggregates.  

For decades, VDOT has not permitted the use of carbonic aggregates for surface pavements for roads with higher traffic volumes and speeds. Carbonic aggregates are generally limestone products. The geology in Virginia is such, that most all the aggregate that is produced west of the Blue Ridge Mountains is carbonic. Therefore, much of the aggregate required for surface pavements in the western part of the State had to be imported, in some cases from nearly 100 miles away. Transporting non-polishing aggregate into these regions is costly and can cause paving project delays.

A couple years ago, VTCA suggested VDOT Materials and the Research Council consider conducting research that will provide a polish value to carbonic aggregates. Many other states do permit limestone in surface pavements based on an established polish value.