Kewanee airport runway rehab
The Kewanee Municipal Airport in Kewanee, Illinois, is a general aviation facility that also accommodates agricultural and business aircraft operations. Serving as the home for 21 based aircraft, Kewanee Municipal sees 12,000 operations per year.
The airfield consists of two runways, 1-19 and 9-27. Runway 9-27 (4,500 feet by 75 feet) is designed for B-II aircraft, while Runway 1-19 (3,200 feet by 60 feet) handles the airport’s B-I aircraft. Both runways have a partial parallel taxiway.
Hanson assisted the Kewanee Airport Authority with the rehabilitation of Runway 1-19, which needed milling, crack repairs and overlay. The condition of the airport’s crosswind runway had deteriorated because of weather-related stresses and age. Airport leadership had observed over the years that the pavements had not performed as anticipated, and rehabilitation and crack repairs were inadequate. As the project design began, we researched alternatives to treat and create a longer-term solution for the pavement cracking.
Ultimately, Hanson determined that placing a fiberglass grid fabric over the entire runway milled surface prior to overlay would provide the necessary strength and prevent reflective cracking through the new surface.
To complete the rehabilitation of the pavement section, which consisted of 5.5 inches of asphalt on 7 inches of crushed aggregate, Hanson milled 2.5 inches and repaired the remaining cracks. To prevent the rapid reappearance of reflective cracking, we used a geogrid beneath the overlay to disperse the stresses of the cracks. The decision to use the geogrid was based on the cracking that had previously been repaired on Runway 9-27. Many cracks were repaired and protected at that time with a 5-foot-wide strip of geogrid, and several of those locations had begun to exhibit cracks at what would be the limits of the geogrid. Hanson determined that placing a continuous layer of geogrid beneath the overlay would greatly minimize cracking and extend the life of the overlay.
Once the crack repairs were completed and the geogrid was installed, an overlay was placed over all the pavement areas, with a nominal depth of 2.5 inches. Hanson chose this depth so future milling won’t compromise the fabric, the final lift of the previous overlay can be removed and no slivers will remain that could cause complications during construction.
The project team also provided an environmental review for a categorical exclusion that the project required.
Hanson worked with the airport authority to complete the project in two phases to minimize the impact on airport tenants and users.