A highway expansion in Arizona is using an unusual material beneath the road: foam made from 100 percent recycled glass. The lightweight fill is being placed at 19 locations along the I-17 Improvement Project between Anthem Way and Sunset Point, where additional lanes are being built along a 23-mile stretch of interstate.
The material may look like ordinary white gravel from a distance, but its purpose is far more specific. Arizona transportation officials are using Ultra-Lightweight Foam Glass Aggregate to help protect existing concrete box culverts from the added weight of the expanded roadway. It is a construction solution that turns discarded glass into structural fill while addressing a problem created by widening an older highway.
