RECOMMENDATIONS AND PRODUCTS FROM NCHRP PROJECT 9-7 FIELD PROCEDURES AND EQUIPMENT TO IMPLEMENT SHRP ASPHALT SPECIFICATIONS

This paper presents a brief overview of quality control and quality assurance (QC/QA) procedures for the field implementation of the Superpave material specifications and mix designs, which are developed by the National Cooperative Highway Research Program (NCHRP) project 9-7 on the basis of experimental data obtained from field paving projects constructed during the course of the project. The paper assumes a familiarity with the Superpave mix design procedures including the use of the Superpave gyratory compactor (SGC). The project developed QC/QA procedures for mixes designed using the Superpave volumetric mix design method (originally termed Superpave level 1), as well as for mixes designed with Superpave level 1 and Superpave level 3 design procedures (now termed abbreviated and full mix analyses). A summary of the products delivered by the research project include: (1) a QC/QA plan for field production and lay down of HMA in accordance with Superpave material specifications and mix design; (2) suggested guidelines for Superpave plant produced mix and project placement adjustments; (3) a training program for qualifying technicians using the procedures set forth in the QC/QA plan; and (4) two field testing devices that support the SGC for QC practices and provisional test procedures. For the covering abstract of the proceedings, see IRRD 490713.