11-Story Downtown Office Complex Expansion
IMEG provided structural engineering for a 310,000-sf expansion to the north side of Bedrock Detroit’s existing 1 million-sf office building for the One Campus Maritus complex – which includes Quicken Loans headquarters. In addition to office space, the expansion also includes 27,000-sf of flexible event space, with a pre-function area and main event area. There is also a 5,500-sf outdoor wraparound terrace that overlooks Detroit’s bustling central business district.
The 11-story infill addition is supported by the existing 4-story structure. The existing building was fully modeled to analyze for current building code requirements, specifically updated wind and seismic requirements. New beams tied into existing columns and spandrel beams prior to removing the existing facade. Floor slabs poured up to the face of existing facade, and the remaining strip of slab was infilled after new construction was enclosed, existing facade was removed.
Two new elevator shafts were added within the existing building serving all 15 floors and two basements. Two existing elevators extended up to serve the penthouse floor. Existing 36” steel girders were modified to make room for elevator openings. The auditorium on penthouse level was acoustically insulated with floating slab floor and concrete roof slab above.
The IMEG team also designed the foundation for the tower crane, which consisted of 7 ft. thick above-ground pile cap supported by micro-piles to avoid damaging utilities below the ground surface (micro-piles were located to thread between utilities).