The canopy is comprised of blue glass on five “flowing” (overlapping) cantilevered built up plate boxes spanning approximately 90’-0 and supported from 3 large 38” pipe columns supported with custom poured castings. Over 90% of the total weight of the project (approximately 324,000 lbs.) is located in the steel arms that outstretch 68’ in one direction and 27’ in the opposite to make a canopy structure. The steel was fabricated and coated in Houston, Texas and shipped to Chicago in five sections on specialty heavy haul trailers. The primary challenges faced during fabrication were fixturing the structure as a whole assembly, and compliance with the Architecturally Exposed Steel aesthetic requirements. The AESS requirement meant that tolerances were cut in half, joint gaps were minimized, and all welds had to be continuous with a uniform and smooth appearance within close visual proximity. The 90’ x 60’ footprint was all fabricated under roof in an enclosed facility. The cantilevered plate boxes were fabricated out of two inch, High-Strength Low Alloy 50ksi yield plate incorporating a majority of Complete Joint Penetration welds accomplished with the Sub Arc Welding Process.
