|
Key Facts |
Bridge Name | Type | Road | Location | City | Crossing |
|
Congress Parkway Bridge |
Bascule (Truss) |
Congress Parkway |
Cook County, IL |
Chicago |
Chicago River South Branch |
|
Technical Facts |
|
Construction Date |
Structure Length | Roadway Width | Approach Spans | Navigational Vertical Clearance |
| 1956 | 335 Feet | 73.8 Feet | 2 Steel Stringers | 22 Feet |
I have no idea how HABS HAER chose which bridges to include on their website. They included the Columbus Drive Bridge which was built in the 70s, and between being both relatively new and completely ugly, I refuse to include it, yet they didn't include this bridge, which while among the newer of Chicago's bridges, is not that new and is one of the strangest of Chicago's bridges.
At first glance, this bridge might appear to be like one of the other deck truss bridges in Chicago like on Ohio Street, which shares the common trait today of serving as a glorified expressway onramp. However if you look at the trusses and see how the diagonals follow a v-pattern, it becomes clear that this bridge is using a Warren truss configuration. The Warren truss configuration is not unusual in general, but the Pratt configuration is used on all the other highway deck, pony, and deck-pony combination truss bascule bridges in Chicago. This is the only one to use a warren configuration! I have no idea why this bridge uses a different configuration, but it certainly helps make this bridge interesting and allows it to stand out from the crowd.
