Gall Zeidler Consultants provided preliminary and detailed designs for the waterproofing of the new underground subway tunnels for a new Airport Express terminal station at Chicago O’Hare Airport. The station connects to the existing subway tunnels of the CTA’s Red and Blue lines.
Gall Zeidler Consultants also provided consulting and design services on the tunnel’s preliminary design that called for oblique intersections resulting in large openings. The preliminary design called for New Austrian Tunneling Method / Sequential Excavation Method (NATM / SEM) construction with systematic pre-support, shotcrete initial and permanent linings, and staged tunnel excavation..
2004 – 2005
250 feet (76 meters)
Fill, Young Soft Clays; Groundwater Table Above the Tunnel Roof
Approximately $250 Million
Chicago Transit Authority (CTA)