Stacey D. Diefenderfer, Ph.D., P.E.

Education:

• Ph.D., Civil Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA
• M.S., Civil Engineering, Virginia Polytechnic Institute and State University
• B.S., Civil Engineering, Virginia Polytechnic Institute and State University

Registration:

• Registered Professional Engineer, Commonwealth of Virginia

Memberships:

• FHWA Asphalt Pavement and Materials Technical Feedback Group
• FHWA Warm Mix Technical Working Group (2009 – 2012)
• Transportation Research Board
  • Chair - AFK30 Non-binder Components of Asphalt Mixtures (2015 – 2020)
  • Chair - AKM30 Asphalt Materials Selection and Mix Design (2020-2021)
  • Member - AFK20 Asphalt Binders (2005-2017)
  • Member - AFK30 Non-binder Components of Asphalt Mixtures (2007-2015)
  • Member - AFK50 Structural Requirements of Asphalt Mixtures (2012-2020)
  • Member - AKM30 Asphalt Materials Selection and Mix Design (2021-2022)
  • Member - AKM40 Asphalt Mixture Evaluation and Performance (2021-2022)

• National Cooperative Highway Research Program (NCHRP)
  • Panel 09-22 Beta Testing and Validation of HMA PRS
  • Panel 09-49 Performance of WMA Technologies: Stage I -- Moisture Susceptibility
  • Panel 09-49A Performance of WMA Technologies: Stage II - Long Term Performance
  • Panel 09-50 Performance Related Specification for Asphaltic Binders Used in Preservation of Surface Treatments
  • Chair - Panel 09-55 Recycled Asphalt Shingles in Asphalt Mixtures with Warm Mix Asphalt Technologies
  • Panel DTFRS-01 TFRS Project Panel on Quality (QA) Aspects of Performance Related Specifications (PRS)
  • Chair – Panel 09-68 Recycled Asphalt Materials: Binder Availability and Its Impact on Mix Performance
  • Synthesis Panel 50-14 Practices for Fabricating Asphalt Specimens for Performance Testing in Laboratories
  • Synthesis Panel 52-17 Use of Recycling Agents in Asphalt Concrete Mixtures

• Association of Asphalt Paving Technologists
  • Board of Directors - Director at Large
  • Board Liaison – Newer Member Committee
  • Member – Membership Committee

• ASTM International – Member
  • Member – Committee D04 Road and Paving Materials
  • Member – Subcommittee D04.21 Specific Gravity and Density of Asphalt Mixtures
  • Member – Subcommittee D04.26 Fundamental/Mechanistic Tests
  • Member – Subcommittee D04.30 Methods of Sampling

• International Society for Asphalt Pavements (ISAP)

Awards:

• VTRC Jack H. Dillard Best Paper Award, "Mechanistic-Based Evaluation of Performance Thresholds for Balanced Mix Design Asphalt Surface Mixtures" (with Habbouche, Boz, Underwood and Othman), 2024
• VTRC Jack H. Dillard Best Paper Award, "Simple and Practical Tests for Rutting Evaluation of Asphalt Mixtures in the Balanced Mix Design Process" (with I. Boz and J. Habbouche), 2023
• VTRC Tilton E. Shelburne Award, 2022
• VTRC Jack H. Dillard Best Paper Award, "Balanced Mix Design for Surface Asphalt Mixtures: Phase I: Initial Roadmap Development and Specification Verification" (with I. Boz and J. Habbouche), 2021
• W. J. Eammons Award for Best Paper, Association of Asphalt Paving Technologists, 2016
• VTRC Jack H. Dillard Best Paper Award, 2015
• VCTIR Horizon Award for Outstanding Productivity and Achievement, 2014
• Outstanding Young Alumni Award, Via Department of Civil and Environmental Engineering, Virginia Tech, 2013
• VDOT Commissioner's Award for Outstanding Achievement - Innovation and Quality Improvement, 2011
• VCTIR Horizon Award for Outstanding Productivity and Achievement, 2011
• VTRC Jack H. Dillard Best Paper Award, 2006
• Dean's List for Teaching Excellence, College of Engineering, Virginia Tech, Spring 2000
• Charles E. Via Doctoral Fellowship, Charles E. Via Department of Civil and Environmental Engineering, Virginia Tech, Fall 1999 - Spring 2003
• Dean's List for Teaching Excellence, College of Engineering, Virginia Tech, Spring 2000

Current Projects

Reports

Team Membership