41st Street Bridge over Lake Shore Drive, Chicago, Illinois Architecture Photos

41st Street Bridge in Chicago, IL

Jun 8, 2020

41st Street Bridge, Chicago

Architects: Cordogan Clark

Location: Chicago, Illinois, USA

The City of Chicago, through an international design competition called “Bridging the Drive,” has constructed a new signature pedestrian bridge at 41st Street. The project’s primary goals were to connect the Bronzeville neighborhood to the west of the bridge with the lakefront with an iconic structure that results in a dynamic, welcoming, and memorable experience for its users.

The 41st Street Bridge is a major civic project that provides bicycle and ADA-compliant pedestrian, wheelchair, and stroller lakefront access for neighborhoods to its west. Before, Lakeshore Drive and the train created an enormous barrier.

With its twin inclined arches on reverse curves, the 41st Street Pedestrian Bridge structure is unique in the world. Unlike typical arch bridges which are symmetric in horizontal and vertical directions, the 41st Street arch spans are on reverse curves with a long crest curve that rises 7’ (2.13 meter) higher between the arches than at the outside ends of the arch at the approaches.

Its arches are inclined at 30 degrees from vertical, and the deck rib is curved on a 400’ radius that is supported by hangers on one side only. The 1,500-foot (457.2 meter) long bridge creates a large, graceful S-curve that echoes the park’s Olmsted walkways to extend the lakefront parkway west. It curves horizontally and vertically, creating an urban promenade that is unique, welcoming, and memorable.

Its height and length are determined by providing a rise sufficient to provide clearance above the commuter train and Lake Shore Drive, yet also allowing a slope that is gentle enough for wheelchair use Its slender, minimal detailing provides excellent views to and from all points: To allow for surveillance and design out hidden areas. Users are gently guided to spectacular city views in all directions.

The bridge projects outwards to create grand balconies at midspan. It glides gently to rest at each end of its span, with ramps supported on a rusticated concrete base that tapers into the landscape to help the bridge blend with and extend the park environment. Its west ramp hugs the east boundary of a park, creating a sculptural backdrop and low wall between the park and the train.

The simple and clean structural detailing uses large 4’ diameter (1.2 meter) steel tube and plate sections to support a 20’ wide concrete deck. Its radiused railings raise the bridge’s curves vertically, reinforcing its dynamic sculptural form.

Prior to construction of the new bridge, residents had to travel more than a half mile to the nearest bridge crossing the railroad tracks and Lake Shore Drive to reach the lakefront. The new 41st Street Pedestrian Bridge links the recently redeveloped neighborhood on the west with the lakefront trail and 41st Street Beach on the east. The bridge was constructed to accommodate pedestrians, bicyclists, people with disabilities and emergency vehicles.

To be fully accessible and usable, the bridge has both ramps and stairs at both ends. The new bridge has been developed to minimize the landing footprint within the adjacent parks while integrating accessibility to the bridge.

With its lean, muscular, dynamic form, the 41st Street Bridge is in keeping with Chicago’s tradition structural expressiveness: Form, function, and structure are one.

Additional Data: Hillsdale Fabricators fabricated the 41st Street Bridge, Chicago’s new pedestrian bridge. The steel bridge weighs 676 tons and spans a total of 750 feet over Lake Shore Drive and Metra commuter rail lines. It connects Williams-Davis Park with the Lakefront Trail, which runs along the perimeter of Lake Michigan.

The bridge is comprised of induction-bent 36-inch diameter and 48-inch diameter pipe with shop-welded box girders. Hillsdale shipped the bridge to the jobsite in 28 large, built-up pieces. The largest of these pieces weighs approximately 40 tons with a width of 24 feet and a length of 60 feet.

Prior to shipping, the bridge was preassembled at Hillsdale’s shop in five groups to ensure that fit-up could be duplicated in the field. The longest of these five preassemblies is 243 feet in length.

Project Highlights
Main span dual spine is 48” and 36” diameter 1” wall pipe that cambers and sweeps.

Awards
Chicago Building Congress
2019 Merit Award Winner – Infrastructure Construction

CMAA (Construction Management Association of America)
Chicago Chapter 2019 Construction Management Achievement Award
National Award Winner in the Category Transportation: Construction value less than $50 Million

SEAOI – Structural Engineers Association of Illinois
2019 Excellence in Structural Engineering
Best Bridge/Transportation Project

ASCE
2019 Outstanding Civil Engineering Achievement Award $10M to $35M

ENR 2019 Regional Best Project Awards Submittal
ENR Midwest
2019 Project of the Year & Best Project – Landscape/Urban Development

ENR 2019 National Best of the Best Project Award
2019 Project of the Year – Landscape/Urban Development
Global Future Design Award 2019 / Urban Design & Architecture Awards
NCSEA (National Council of Structural Engineers Association)
2019 Excellence in Structural Engineering Award
2019 Top Bridge Project
2019 Best Poster Graphics

Roads & Bridges
Named the #3 bridge project of 2019

ACEC
2020 Engineering Excellence Award – Honor Award

CISCO – Construction Industry Service Corporation
2019 Top Infrastructure Project Award

National Steel Bridge Alliance
2020 Prize Bridge Merit Award – special purpose category

Articles
ASHE Scanner Fall 2019 Edition (American Society of Highway Engineers)

41st Street Bridge, Chicago, Illinois – Building Information

Design Architect: Cordogan Clark

Lead Civil and Structural Engineer & Engineer of Record: AECOM
Construction Engineering Firm: Transystems
Contractor: F.H. Paschen
Landscape Architect: Terry Guen Design Associates
Owner/Client: City of Chicago Department of Transportation