1923: (
Bridge Hunter;
HAER)
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HAER WIS,5-GREBA,5--7
7. John N. Vogel, Photographer, August 1995 VIEW TO NORTH. TWO SPANS OPEN. - Main Street Bridge, Spanning Fox River on Main Street, Green Bay, Brown County, WI |
Significance: The Main Street Bridge is a double-leaf, Strauss Underneath Counterweight bascule bridge. It is significant as the only bridge of this type in Green Bay. With its symmetrical design including four houses at each comer, the bridge is also significant as an excellent example of the Spanish Eclectic architectural style adapted for use in an industrial facility.
[
HAER-data, this is effectively a general history of movable bridges.]
I've seen diagrams of
Strauss' overhead and heel designs. But this is the first time I have seen a diagram of the Underneath Counterweight design. Unfortunately, these diagrams don't make sense. The whole purpose of the counterweight is to move the center of gravity of the span close to the main trunnion. The center of gravity should not be almost halfway across the channel as indicated by the diagrams. I discuss this further in the
SUC design.
Here is how that source diagramed the other two designs.
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| Photo via BridgeHunter-1923 |
This bridge appears to be another example of "newer is not necessarily better." The author of the Historic Bridges web site left this comment BridgeHunter-1998:
Posted July 23, 2010, by Nathan Holth (form3 [at] historicbridges [dot] org)This 12 year old bridge has been closed three times over its life for repairs. Here is news on the latest closure:
http://www.greenbaypressgazette.com/article/20100723/GPG0101...This bridge points to two problems:
-Modern bridges are not as reliable and long-lived as historic bridges.
-Alternatives to salt for deicing bridges need to be researched and employed.
And other comments explain that it gets stuck open for hours rather frequently.
The original bridge was perpendicular to the river because Main Street used to be further south.
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| 1954 Green Bay West Quad @ 24,000 |
Then an urban renewal project in the early 1970s moved Main Street further north "about 1/4 of a block to the north of its original location to accommodate the Port Plaza Mall (now demolished) and the Main Street parking garage." This introduced a tight S-curve at the east end of the bridge. [Erik Eisenheim comment in BridgeHunter-1923]
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| 1982 Green Bay West Quad @ 24,000 |
So they built the replacement bridge on an angle to remove the S-curve.
The angle does create a challenge for the big freighters that use the river.
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