DEARBORN CENTER, 131 S. Dearborn Street, Chicago

Dearborn Center, built for use by Bank One Center, is an office tower with a bustle, offering 40,000-sq-ft floors at the lower levels.  All levels offer raised floors with under-floor air distribution.

The superstructure features a steel frame and a steel braced core, selected to limit building weight and allow reuse of existing caissons.

Koz Sowlat served as a principal in charge of structural engineering.