The Grainger College of Engineering
Illinois Center for Transportation

New FAA research to advance airport pavement modeling, development of surface mixes

3/19/2026 Sameer Sanadi

Illinois Center for Transportation is leading two Federal Aviation Administration projects. The projects aim to advance airport pavement design through improved modeling of reflective cracking and investigate the application of stone-matrix asphalt mixtures for airfields.

Reflective Cracking Model for Airport Asphalt Overlay Design — Phase 2

A multiscale generalized finite element method model of a section of an asphalt-overlaid concrete airfield pavement. The reflective crack spans the width of a slab but is only 13 mm long at the start of the simulation. Researchers will use stress intensity factors extracted from the GFEM solution to train artificial neural network models.

Arizona State University leads this project with the University of Illinois’ Imad Al-Qadi, Grainger Distinguished Chair in Engineering and ICT director, and C. Armando Duarte, Nathan M. Newmark Distinguished Professor in CEE.

An asphalt overlay, or top layer, is placed on top of existing pavement to extend its service life. A challenge with overlays is how to predict and control reflective cracking, in which cracks appear on the surface because of movement in underlying pavement layers like concrete slabs.

This FAA-funded research project focuses on improving predictive modeling of reflective cracking in airport asphalt overlays placed on jointed concrete pavements. Current predictive models do not account for the transfer of loads between concrete slabs or when the interface between asphalt and concrete is fully or partially debonded, or separated.

The team will integrate interface and tire contact models into numerical modeling approaches and establish joint load transfer using springs with varying stiffness values. They will verify their developed model using benchmark problem sets.

They will implement the new capabilities within a mechanistic-empirical framework and develop artificial neural network models, a form of AI that learns and identifies patterns from data, to capture different scenarios and select appropriate transfer functions. They aim to implement the developed model into FAARFIELD, FAA’s software for airport pavement design.

The project runs through June 2028.

Evaluating Stone Matrix Asphalt (SMA) for U.S. Airfields

Photo Credit: Pascal Meier, Unsplash
ICT-led FAA research is evaluating stone-matrix asphalt as a durable paving option for U.S. airfields, with a focus on runway performance, safety and long-term cost effectiveness.

This study, in collaboration with Auburn University and The Heritage Group, will evaluate the use of stone-matrix asphalt, a highly durable pavement mixture, for use in airfield pavements and as a potential addition to FAA specifications.

The team, led by Al-Qadi, will design and assess SMA’s potential structural and functional performance, including resistance to rutting, cracking, raveling and moisture damage, as well as operational considerations such as foreign object debris risk, surface friction and hydroplaning potential.

They will develop a balanced mix design methodology tailored for airfields to address the unique loading and environmental demands of airport pavements. They will also conduct a life cycle cost analysis to quantify long-term economic benefits compared to standard FAA P-401 mixtures.

Al-Qadi’s team will create guidelines for the use of SMA, covering materials, mix design, construction and maintenance practices, along with recommendations for friction performance and runway grooving where appropriate.

The project, funded by FAA through the National Asphalt Pavement Association, is scheduled to conclude December 2027.