47929 SOM038

Dearborn Tower

Design/Completion 1988 Chicago, Illinois, USA Bramalea, USA 2,500,000 square feet

Reinforced concrete core with structural Steel superstructure Granite, stainless Steel, painted aluminum

The project is located within a concentration of government and commercial offices along the Dearborn Street corridor. The five-story base occupies the entire site, and is related to similarly scaled commercial buildings as well as the surrounding retail environment. The base is part of a continuous sequence completing the wali of masonry facades that surround the Federal Center. As the Federal Center buildings are freestanding steel-and-glass objects within a masonry wali, the tower is conceived as a glass-and-steel object emerging from within the enclosure.

The structural system incorporates a central core element of concrete shear walls in a cruciform configuration. The exterior structure is tied to the core with two-story-deep trusses at the mechanical floor levels, expressed as buttresses at the crown. A glass and stainless Steel curtain wali provides unobstructed views from all office floors, angling away from the central figurę in a series of sawtooth-like setbacks.

1    Model: tower top

2    Model: Dearborn Street elevation

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