Results from VDOT's pilot project using volumetric properties and asphalt content for acceptance of asphalt concrete

In 1994 the Virginia Department of Transportation (VDOT) developed a specification for the acceptance of asphalt concrete based largely on Marshall compacted volumetric properties of the mix. A copy of the Special Provision is shown in the Appendix. The development of this specification is consistent with national efforts such as AASHTO and the SHRP asphalt program, emphasizing volumetric properties as being more related to performance than gradation results. A pilot project was placed on 1-95 in the Fredericksburg District by Virginia Paving Co. in June 1994. Over a 3 week period, approximately 24,000 tons of mix were placed in accordance with the Special Provision. This report summarizes the results relative to acceptance and compares results obtained from the contractor, from the VDOT Elko Materials laboratory, and from several VDOT district materials laboratories.