Cortland Street Drawbridge
Cortland Street Drawbridge | |
|---|---|
Chicago, Illinois | |
| Official name | Cortland Street Drawbridge |
| Characteristics | |
| Design | Chicago trunnion bascule bridge[1] |
| Material | Steel |
| Total length | 39 metres (128 ft)[2] |
| History | |
| Designer | John Ernst Ericson[1] and Edward Wilmann[3] |
| Opened | 1902 |
Chicago Landmark | |
| Designated | July 24, 1991 |
| Location | |
 | |
The Cortland Street
Design
This is the bridge type for which Chicago engineers are most well-known. The trunnion bascule has two bridge leaves with pivots on the opposing riverbanks and are raised on large trunnion bearings by large counterweights which offset the weight of the leaves. They take their names from the French word bascule, meaning seesaw, and the counterweights.[6] Unlike most of the subsequent bascule bridges of Chicago, the gear rack that moves this bridge is visible above the roadway, on the curved arcs at each end of the superstructure.
History
The bridge was built under the supervision of Mayor
This is the second bridge built on this site, which replaced a swing bridge with a mid-river pier supporting the swing span. The current bridge eliminated the need for the mid-river pier, allowing more room in the shipping channel.
While the machinery of the current bridge is intact, the bridge is no longer operable and the leaves are clamped together.[3]
The bridge was traversed by
The Cortland Street Bridge is currently used for two-way vehicle traffic, pedestrian, and bicycle traffic.
See also
References
- ^ a b "Cortland Street Drawbridge". City of Chicago Department of Planning and Development, Landmarks Division. Archived from the original on 2008-06-21. Retrieved 2008-07-16.
- ^ Cortland Street Bridge at Structurae
- ^ ISBN 0-471-14385-5.
- Historic American Engineering Record. Washington, D.C.: Library of Congress. Retrieved July 18, 2021.
- ^ "Cortland Street Drawbridge". American Society of Civil Engineers. Retrieved January 29, 2022.
- )
- ^ "Cortland Street Bridge (West Clybourn Place Bridge)". HistoricBridges.org. Retrieved July 18, 2021.
- ^ )
- ISSN 0266-7452.
External links
- Historic American Engineering Record (HAER) No. IL-138, "Chicago River Bascule Bridge, West Cortland Street, Spanning North Branch of Chicago River at West Cortland Street, Chicago, Cook County, IL", 9 photos, 2 data pages, 2 photo caption pages
