A Mechanistic-Empirical Pavement Design user group met the week of December 7, 2020, in a 3-day web conference with about 200 participants, to discuss ongoing developments with AASHTOWare (American Association of State Highway and Transportation Officials) Pavement ME Design, according to Eric Ferrebee, Technical Service Director-ACPA and resident pavement design expert. AASHTOWare Pavement ME Design is the next generation of AASHTOWare® pavement design software, which builds upon the mechanistic-empirical pavement design guide, and expands and improves the features in the accompanying prototype computational software. Mechanistic-Empirical Pavement Design user group
Hosted by APTech, the meeting provided AASHTO and Applied Research Associates, Inc. (ARA) with the opportunity to discuss Pavement ME design developments. ARA is the technical, in-depth, and diversified research, engineering, and technical support services that provide answers to complex and challenging problems in the physical sciences. In addition to the host and sponsoring organizations, the meeting also included
Key stakeholder groups:
—Federal Highway Administration (FHWA)
—State DOTs
—Industry
—Consultants
—Members of academia
—Canadian user group headed by Tim Smith, Cement Association of Canada (CAC)
One major development was the announcement that AASHTO is planning an online version of Pavement ME sometime in 2022. The web version of the highway pavement thickness design resource will be similar to the web-based pavement design portal, PavementDesigner.org co-developed and currently managed by American Concrete Pavement Association (ACPA), with support from Portland Cement Association (PCA), RMC Research & Education Foundation, and the RCC Pavement Council. For the ISCP October 2020 article on PavementDesigner.org titled “Upgrades to “PavementDesigner.org” — Design Platform Now Better Than Ever!”, please go to: www.concretepavements.org/2020/10/15/upgrades-to-pavementdesigner-org-concrete-pavement-thickness-design-platform-now-better-than-ever/
The 3-day web conference also had the opportunity to hear updates on research studies and presentations, including:
• Updates on various National Cooperative Highway Research Program (NCHRP) Research Studies, which are being evaluated for inclusion into Pavement ME. Eric stated two of note are on:
—The use of geosynthetics in design
—The impact of underlying concrete slabs on overlay design
• DOTs updates on their status of implementation with Pavement ME. This is summarized in their yearly reports which can be found on the user group website.
• Two concrete pavement-related presentations by:
—John Becker, President-ACPA, Pennsylvania Chapter
Gave an update on his efforts to use Pavement ME to develop maintenance schedules for PennDOT’s long-life concrete pavement designs.
—Julie Vandenbossche, Professor-University of Pittsburgh
Provided program training on how to design concrete overlays, including:
• Bonded concrete overlays on asphalt
• New design tool for unbonded concrete overlays of concrete pavements
Many states are still in the process of implementing Pavement ME. Eric said, “This can be a large effort, as many states want to calibrate the program for local performance and also build traffic and materials libraries. ACPA developed a perspectives piece that supports the point that Pavement ME with national calibrations is a good place to start for concrete pavements, particularly for states that don’t have enough data to calibrate.”
ACPA’s stance has long been that Pavement ME is a better tool than AASHTO 93, and educational efforts by ACPA engineers and others are aimed at providing both the training and tech transfer to support Pavement ME as it continues to evolve.
For the AASHTOWare website, please go to: https://www.aashtoware.org