Asphalt Mix Design Method for Permeability (05-0483)**
George William Maupin, Virginia Center for Transportation Innovation and Research

Because of the observed porosity of new Superpave mixes, the Virginia Transportation Research Council conducted several investigations of permeability. As a result of these investigations and other related national studies, a mix design permeability test method was developed. The method involves testing a group of specimens prepared in the lab at a range of air-void contents and developing a permeability-void regression plot. From the regression, the permeability of pavement can be estimated. The purpose of this project was to compare results between two labs using mixtures from 11 paving projects. There was general agreement between permeability-air voids regressions resulting from the testing for the two labs. In addition, testing of cores from six of the projects indicated that the lab method estimates pavement permeability rather well. Implementation of the test method by the Virginia Department of Transportation is discussed.