A panel of design and construction industry professionals identified National and Merit winners in three categories based on total constructed value: projects greater than $75 million; projects $15 million to $75 million; and projects less than $15 mil- lion. In addition, the panel awarded a Presidential Award of Excellence in Engineering to two projects for structural engineering accomplishment. The IDEAS 2 program also recognizes the importance of teamwork, coordination, and collaboration in fostering successful construction projects. Awards for each winning project are presented to the project team members involved in the design and construc- tion of the structural framing system, including the architect, structural engineer of record, general contractor, owner, and AISC member fabricator, erector, detailer, and bender-roller. The awards are presented to the team members at ceremonies held at each of the winning projects during the year. “We celebrate these projects and appreciate the savvy, creative people behind them for showcasing the beauty and usefulness of structural steel,” said Charles J. Carter, Ph.D., S.E., P.E., president of AISC. “Our hearty congratulations to the award-winning teams for a great compilation of excellent solutions!” Following are the 2018 award-winning projects in each category. Projects greater than $75 million National Award: 150 North Riverside, Chicago — The new 54-story, 1.25 million- square-foot, Class A office, pre-certified LEED Gold tower spans across seven active Amtrak lines, was constructed using cranes balanced on barges, and used lifts of the largest steel sections in the world. The tower features a narrow structure at its base and a compact footprint, which opens up to column-free floors above. Just 85 feet at its widest, the site is hemmed by the river and a 30-foot setback to the east, active Amtrak lines to the west, and Lake and Randolph Streets to the north and south. Above Level 8 (the first full floor positioned more than 100 feet above the plaza), the concrete core-supported tower looks like a typical 46-story steel-framed office building. From Levels 4 to 8, a four-story transfer truss with sloping columns “funnels” the tower out of Amtrak air-rights space on the west and onto the developer’s land in a footprint equal to just 30 percent of the tower’s floor area. Although not similarly restricted, the building’s east side was also designed to slope inward to balance forces and provide open access to the expanding Chicago Riverwalk. All 16 sloping columns along the east and west building faces are 65-ksi W36x925 — the largest and strongest rolled steel shapes in the world. At the furthest north and south column lines, the sloping col- umns are part of a four-story steel truss. Each truss is supported by two mega-columns, each comprised of two W36x925 sections joined together to create an economical and compact super-column carrying 13,500 tons. Between the north and south column lines, the base of each sloping column bears on the central concrete core. Structural engineer for 150 North Riverside is Magnusson Klemencic Associates, Inc., Seattle. National Award: World Trade Center Transportation Hub (The Oculus), New York City — The main transit hall in the new multi-billion dollar transit station at the tip of Manhattan Island will serve more than 200,000 travelers each day. The Oculus con- sists of two parallel arches spanning across a 300-foot-long oval-shaped opening in the transit hall roof slab, and reaches a crown height of more than 100 feet. The arches are supported by columns spaced approximately 7 feet apart — the same distance that the columns of the twin towers were spaced. The spaces between the columns and the gap between the arches are covered in glass, which allows natural light to illuminate the 90,000-square-foot main hall. The “wings” of the dove consist of variable-length rafters that extend from the arches to form a roof-like structure, the largest of which is 197 feet long (equivalent to an 18-story building). The entire structure used a total of
150 North Riverside, Chicago. Photo: Magnusson Klemencic Associates, Michael Dickter
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june 2018
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