The Federal Reserve Bank of Minneapolis

Built in 1972, the Federal Reserve Bank Building consists of a 12-story steel-framed structure designed by the renowned architect Gunnar Birkerts.  The unique steel framing is composed of a catenary suspension cable system consisting of prestressed steel wires and beams. The building floors are supported from the catenaries by means of columns and hangers. The catenaries are supported at the end by concrete towers located at each end of the building, very much like a suspension bridge.

The building encountered serious problems with respect to condensation and corrosion of the steel framing. Other deficiencies included water leakage, deterioration of window frames and exterior curtain wall, degradation of fireproofing and asbestos insulation, and corrosion of prestressing wires.

RRJ conducted comprehensive field investigations to determine the extent of the corrosion damage and evaluated the structural integrity of the catenary framing system.  Window frames were disassembled to observe corrosion damage. Monitoring of the windows for temperature, humidity, and pressure were conducted over a five-month period. At the end of the investigation phase, conceptual recommendations were developed by RRJ to repair the curtain wall, eliminate condensation, and repair the corrosion damage.

Design problems, along with asbestos contamination, led the Federal Reserve to later move into a new complex and sell this building