City: District of Columbia
General Contractor: Balfour Beatty Construction
Design/Build Specialty Contractor: Schnabel Geostructural Design & Construction
Schnabel Geostructural Design and Construction designed and installed over 130,000 square feet of excavation support for the Capitol Crossing project in Washington, DC. The Capitol Crossing project is an air rights building that spans over I-395 and required several innovative solutions from Schnabel including soldier piles, lagging, tiebacks, braces, underpinning, single auger soil mixed (SASM) walls, micropiles, and tiebacks through a slurry wall installed by another contractor to accommodate this unique project with excavation depths of up to 72 feet. Several structures including the Holy Rosary Church, which had a historic Bell Tower over 85-foot tall, the Casa Italiana, and a modern office building were supported by a combination of conventional hand-dug underpinning pits, bracket piles, and stiff SASM walls. An automated monitoring system was used to provide continuous data on the system’s performance.