PROJECT OF THE YEAR: STRUCTURES $25 MILLION–$75 MILLION
Cermak-McCormick Place Elevated Green Line Station Managing Agency: Chicago Department of Transportation Primary Contractor: F.H. Paschen, S.N. Nielsen Primary Consultant: T.Y. Lin International Nominated By: Chicago Metro Chapter
T
he Chicago Transit Authority’s Cermak-McCormick Place Green Line Station fills a crucial transportation gap in the Near South Side of Chicago that has been present since the 1977 demolition of the previous station at this location. The $50 million investment made by the Chicago Department of Transportation for the construction of the station will boost the economic investment Chicago Mayor Rahm Emanuel has made in the McCormick Place Convention Center as well as the developing residential neighborhoods in the Near South Side. The new station also adds to the City’s efforts to revitalize the adjacent historic Motor Row area into a bustling entertainment district. This project consisted of building a new, fully accessible station into and around a historic 100-year-old elevated rapid transit structure, while maintaining full transit service. All new work was completed within the limits of the existing right-of-way. The new station’s most distinguishing element is the structural steel tube that serves as a windbreak for the passenger boarding areas. By pushing the structural components outside the platform, the enclosure provides passengers with the maximum open area for boarding and de-boarding while addressing the constrained site, which could only accommodate a 15-foot platform width. Work to accommodate the tube and platforms included adding six reinforced concrete piers located between the existing steel bents.
T.Y. Lin International was retained by the Chicago Department of Transportation for both Phase I and II Design Services for the new station.
built completely independent from the existing track structure so that no additional loads would be applied to the track stringer or bents.
For Phase I Preliminary Engineering, the T.Y. Lin team prepared three alternative station layouts and space plans for each level. T.Y. Lin also submitted documents to show compliance with ADA requirements needed to secure permitting with the City of Chicago Department of Buildings.
Additional work during Phase I included special waste determination, determination of construction phasing to maintain CTA service as well as determine potential weekend shutdowns to accommodate erection of structural elements for the new station. Other work included a CTA system analysis and recommendations for signal, communication and train traction power improvements, a topographic survey, and a geotechnical program. During Phase I, the team coordinated with impacted utilities, performed sewer televising, coordinated with the City of Chicago Board of Underground, and developed a utility mitigation plan.
T.Y. Lin performed a detailed structural inspection of the over 100-year-old existing steel elevated rail structure and provided a detailed structural analysis of the existing steel framing system. The existing structure was rated to determine if any retrofits were warranted. Based on the load rating, it was decided that the new station’s platform would be www.apwa.net
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July 2016
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APWA Reporter
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