Mitigating potential alkali-silica reaction expansion in airfield concrete pavements

Under the previous Airport Pavement Technology Program (APTP) between 2002 and 2006, much research was accomplished. Early alkali-silica reaction (ASR) research had suggested that airfield pavement deicer exacerbates ASR expansion in concrete. However, an APTP-funded Innovative Pavement Research Foundation report (IPRF 05-7) concluded that pavement deicer does not cause ASR in airfield pavements. Further APTP research demonstrated Class F Fly Ash, which is a waste product recycled from coal combustion power plants, to be an effective mitigator of ASR expansion. However, with the slowdown of coal-fired power plants resulting in limited supplies of Class F Fly Ash, other means of mitigating ASR expansion must be found. Research is needed to find alternative materials and methods for mitigating ASR expansion in concrete pavements as well as to develop a new rapid test procedure to identify ASR-susceptible aggregates.

Research team:  Oregon State University, PI: Jason Ideker; the University of Texas-Austin, University of New Brunswick, RJ Lee Group

Project dates: January 1, 2022 – March 31, 2025

Performance engineered mixtures for airfield pavements

Research is ongoing with performance-engineered mixtures for highway pavements. However, the differences between highway and airfield pavements are significant, including different mixture performance requirements. These mixture-related differences need to be evaluated, understood, and cataloged. Procedures and best practices for concrete mixture optimization with airfield pavements need to be developed and incorporated into airfield specifications.

Research team: Oklahoma State University, PI: Tyler Ley; Jason Weiss, Nichols Consulting, Applied Pavement Technology, UNC-Charlotte

Project dates: April 1, 2022 – June 30, 2025

Best practices for rapid repair, rehabilitation, and reconstruction of concrete airport pavements

The aim of the work is to build upon the accelerated construction guide and case studies developed under the IPRF program to develop the guidance and standards for rapid construction projects such that the engineer, airport sponsor, and FAA have guidance they can rely on to provide quality concrete pavements under rapid construction practices.

Research team:  Applied Research Associates (ARA), PI: Scott Murrell; Senseney Engineering, Kiewit Engineering Group

Project dates:  March 1, 2022 – May 31, 2025

Quality Control and Quality Acceptance of Airport Pavement

In December 2018 the FAA released an update to Advisory Circular 150/5370-10, Standard Specifications for Construction of Airports. The updated specification centered around the need for improved quality control and quality assurance of airfield construction. The aim of the work is to develop a best practices manual for quality processes specifically at concrete airfield sites in the context of P-501 and military concrete pavement specifications. In addition, training materials will be prepared to help agency and contractor staff become fully conversant with the material.

Research team:  University of North Carolina-Charlotte, PI: Tara Cavalline; Square One Pavement Consulting, Nichols Consulting Engineers, Hi-Way Paving, Doug Johnson; Tigerbrain Engineering

Project dates:  August 1, 2022 – January 31, 2025

Best Practices for Runway Rubber Removal

This project will produce a guidance document that augments and updates ACRP Synthesis 11 by identifying and documenting best practices for runway rubber removal. It is expected that this information could be utilized by airport operators, maintenance officials, and rubber removal contractors to more efficiently restore runway pavement friction through rubber removal processes while minimizing negative impacts to the runway surface.  Although the primary emphasis is on hydro-blast processes that are sometimes associated with runway damage, the guidance should also identify and address best practices for other rubber removal processes.

Research team:  Applied Research Associates, PI: Aaron Pullen; Jim Hall, Consultant; Pam Phillips, Consultant

Dates:  February 1, 2023 – July 31, 2025

Effects of Diamond Grinding on Airfield Pavements

This project will investigate all relevant aspects of how diamond grinding may or may not impact concrete airfield pavements.  A further objective is to investigate and identify diamond grinding for concrete airfields best practices. The investigation will result in a report that identifies grinding impacts and best practices and provides guidance on diamond grinding that can be used by FAA, Tri-Services, and airport operators for grinding specification development and airfield operations.  The best practices guidance will be supported by a combination of literature search findings, stakeholder interviews, and documentation through case studies of projects involving diamond grinding.

Research team:  Nichols Consulting Engineers, PI: Jeff Stempihar; Wiss, Janey, Elstner Associates; Applied Pavement Technologies

Dates:  February 1, 2023 – January 31, 2025

ACPTP-2023-7 Design and Performance of Thin Concrete Airfield Pavement

Although extensive research and testing were employed in the development of FAARFIELD and the design procedures in AC 150/5320-6G, most of the effort centered around heavily loaded pavement from aircraft with complex gear configurations, without significant consideration for general aviation (GA) airport pavement designed for smaller aircraft. The overall goal of this project is to examine and document the performance of GA airfield concrete pavements that are less than nine inches thick, including concrete overlays on asphalt surfaces and FDR with concrete surfaces.  Information and recommendations from the research are expected to support and aid in the development of improvements for GA airfield concrete pavement design procedures.  In addition, the outcome of this research is expected to support suggested language to update FAA Advisory Circulars and improve GA airport concrete pavement design.

Research team:  Applied Research Associates, PI:  Scott Murrell; Tim Parsons and Richard Speir, ARA; Jim Mack, CEMEX; Jim Hall, JH Consulting, LLC; Chris Senseney, Senseney Engineering, LLC

Project dates:  September 1, 2023 – March 31, 2026

ACPTP-2023-8 Concrete Airfield Paving Continuity – Best Practices Guide

A critical factor in constructing quality airfield concrete pavements is the consistent delivery of concrete to the paver which enables the contractor to maintain steady paver speed and operation.

This research seeks to quantify the impacts to pavement characteristics such as smoothness and air content that may result from the paver slowing down versus stopping completely.  In addition, this project will provide guidance for contractors on managing operations so that material delivery is constant and efficient, relevant to paver speed and associated impacts.

The best practice guidance shall address impacts of paver speed and vibrator speed, along with minimum speeds versus stopping the paver entirely.  The research shall focus on impacts to characteristics that influence pavement performance, including but not restricted to pavement smoothness, consolidation, air void system, and surface finish.

Research team:  Fonte & Company, PI: Matt Fonte; APR Consultants; Nichols Consulting Engineers; Oklahoma State University; Pavement Engineering and Research Consultants; Square One Pavement Consulting; Transtec Group; Jim Lafrenz; University of North Carolina at Charlotte; Wiss, Janney, Elstner Associates; Zachry Construction

Project dates:  February 1, 2024 – May 31, 2027