35th Street Pedestrian Bridge
Photo taken by Roger Deschner in February 2017
License: Creative Commons Attribution-Share-Alike (CC BY-SA)
BH Photo #379185
New, notable bridge, replaced much more humble earlier box-truss and girder bridges.
Unique design may be the only curved cable suspension span in existence. (There are other curved suspension bridges, but they are multiple spans with a curve between, such as Oakland Bay Bridge.) Deck is S-shaped, with one A-shaped tower in the center and one cable. On each half of the deck, the hanger cables extend only to the outer edge of the curve. So each half of the S-curved deck acts structurally like an arch laid on its side, with the cables providing compression as well as vertical support. At the base of the central tower, where the middle of the S-curved deck passes through, the compression forces of the deck halves balance one another. Being self-anchored, the forces at the ends are also balanced, depending more on the strength of the abutments to resist horizontal force, than the strength of the anchorages themselves. It's really a very clever design, visually appealing too. But building it was difficult, requiring extensive falsework to hold the deck up over active rail lines and a highway while the cables were strung. Unlike other suspension bridges, in this case the deck was built first, and then the cables were connected to it. There was no other way to build it.
- Self-anchored suspension bridge over Metra Electric Line, South Shore Railroad, Canadian National Railway, South Lake Shore Drive (US 41), and Lakefront Trail, on pedestrian pathway that is an extention of the 35th Street sidewalks
- Chicago, Cook County, Illinois
- Open to pedestrians only
- Built 2016
- - James McHugh Construction Co. of Chicago, Illinois
- Teng & Associates Inc. of Wauwatosa, Wisconsin
- - Amtrak (AMTK)
- Canadian National Railway (CN)
- Chicago, South Shore, & South Bend Railroad (CSS)
- Metra (METX)
- Wire/cable self-anchored suspension, using a single main cable hung from a single central tower, supporting only one side of S-curved deck. Structurally, each half of the deck appears to function like an arch laid on its side, with the cables providing compression and rigidity in addition to vertical support.
Total length: 620.0 ft.
- Approximate latitude, longitude
- +41.83120, -87.60588 (decimal degrees)
41°49'52" N, 87°36'21" W (degrees°minutes'seconds")
- Approximate UTM coordinates
- 16/449689/4631212 (zone/easting/northing)
- Quadrangle map:
- Jackson Park
- Inventory number
- BH 75712 (Bridgehunter.com ID)
- March 12, 2018: Updated by Roger Deschner: Expanded description of bridge's unique design elements
- March 10, 2018: New Street View added by Roger Deschner
- January 28, 2018: New Street View added by Dana and Kay Klein
- February 19, 2017: Added by Roger Deschner