1939: (
Bridge Hunter;
Historic Bridges;
HAER;
Bridgemeister; see below for satellite image)
I had duplicate posts for the 1939 and 2006 US-1 highway bridges. So this one is now the 1939 bridge. The 2006 cable-stay bridge is
here.
I've been studying David Steinman, a suspension bridge designer. I discovered this is one of the bridges that he designed.
Technologically, the Waldo-Hancock Bridge represents a number of firsts.
It was one of the first two bridges in the U.S. (along with the St. Johns
Bridge in Portland, Oregon, completed in June, 1931) to employ Robinson
and Steinman's prestressed twisted wire strand cables, which were first
used on the 1929 Grand Mere Bridge over the St. Maurice River in
Quebec. The prefabrication and prestressing of the cables decreased the
number of field adjustments required, saving considerable time, effort, and
money. As an additional experiment in efficiency, the Waldo-Hancock
cables were marked prior to construction, ensuring proper setting. This
method had never been used before and proved successful in this instance.
These innovations, invented and pioneered by Steinman, were a significant
step forward for all builders of suspension bridges.
The Waldo-Hancock was also the first bridge to make use of the
Vierendeel truss in its two towers, giving it an effect that Steinman called
"artistic, emphasizing horizontal and vertical lines." This attractive and
effective truss design was later used in a number of important bridges,
including the Triborough and Golden Gate bridges.
The Waldo-Hancock Bridge was noted at the time for its economy of
design and construction. It cost far less than had been appropriated by the
State Highway Commission.
[HAER from me313]
I include this view of the tower since this bridge pioneered the use of a Vierendeel truss in the tower. From a distance, a Vierendeel truss appears to be made with rectangles instead of triangles.
But if you look closely at the cross-members, they have plenty of triangles. I'm lucky that the portal street view in Bridge Hunter still has an image. Note only do the cross-members have lots of triangles, but there are vertical members that run through all three cross-members. The inside vertical members were eliminated in more modern bridge towers.
"Built 1931; bypassed by new bridge 2006-07; Demolished 2012-2013; Removed from NRHP 12-18-2013" [Bridge Hunter] This is evidently another example where 80% Federal funding for a new bridge makes it cheaper for a state to build a replacement than maintain a nice looking bridge. I can understand how they let the cables rot so bad that it would no longer safely hold traffic. But since it was handling traffic, how can it be so bad that it can't be used by pedestrians? It seems like it would take a couple more decades of rotting before it would be too weak to hold itself up. (Pedestrian traffic has to be negligible compared to the weight of the cable and truss.)
It has been replaced by yet another cable-stay bridge.
These construction photos also give us additional views of the Waldo-Hancock Bridge.
In a 2019 satellite image, the only thing left are the piers for the towers.
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John Weber posted
Traveling in Maine I was fortunate to take this photo of these two bridges. Now the old bridge is gone. Taken at the Penobscot River crossing. Called the Historic Waldo-Hancock Bridge. |
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