Thursday, May 9, 2019

1912 Double Decker Steel Bridge over Willamette River in Portland, OR

(Bridge Hunter; Historic Bridges; HAER3D Satellite, 774+ photos)

Photo from HAER ORE,26-PORT,14--14 (CT) from or0291

The 1888 predecessor bridge:
Old Oregon Photos posted
First Steel Bridge, Portland - circa 1888. This is Portland's first steel bridge, from a photo taken shortly after its completion in 1888. It was the first railroad bridge across the Willamette in Portland.
Like the current Steel Bridge that replaced it in 1912, it was a two layer bridge, with railroad tracks on the lower level and pedestrians and carriages on the upper level. Unlike the current bridge, this one was a swing-span design, meaning the center section pivoted to allow river traffic to pass by.
Note the shadow of the photographer in the lower right corner.
George Alderson shared

The 1912 Steel Bridge is significant for its vertical lift design. This is a double-decked bridge; the lower deck is a railroad deck while the upper deck is used for highway and light rail traffic. The two decks may be lifted at the same time, or the lower deck may be raised independently of the upper deck, telescoping into the latter. The Steel Bridge was the first bridge built with this independent lifting system and is the only one of this type existing in the United States today. This type of bridge was designed by J.A.L. Waddell, who engineered the South Halstead Street Bridge inChicago, Illinois, the first significant vertical lift bridge in the United States. [HAER-data]
The bridge is normally 26' above low water. When the lower deck is raised, there is 72' of clearance. Raising both decks provides 139' of clearance. [HAER-data]
The first bridge built at this location in 1888 used steel as its main building material, the first such occurrence in Portland, thus the name the Steel Bridge, which remains on the modern bridge. The current Steel Bridge replaced that first one in 1912, and maintained the tradition of innovation in bridge design set by its predecessor. At the time of its opening, the 1912 Steel Bridge claimed to be the largest telescoping bridge in the world. The telescoping, two-stage lift action of the bridge still functions, allowing the lower rail-carrying deck to lift without disturbing traffic on the upper deck. For larger vessels, both decks can be raised, giving a maximum clearance of 163-ft. [Historic Bridges]
The ABS Bridge also can raise the lower deck up into the upper deck, but the upper deck is fixed. This is the only bridge in the United States that can raise both decks.
Photo from HAER ORE,26-PORT,14--24 (CT) from or0291

Photo from HAER ORE,26-PORT,14--22 (CT) from or0291
Railway Review, p137
[This is a reminder that the reason lift bridges needed such tall towers at the interesting turn of the century is that sailing ships were still common. And we can see that tugboats that are travelling "light" need just the lower deck raised even though they are steam powered and have a tall smokestack.]

LC-DIG-highsm- 51223
Credit line: Photographs in the Carol M. Highsmith Archive, Library of Congress, Prints and Photographs Division.
Carol M. Highsmith's photographs are in the public domain.

LC-DIG-highsm- 51345
Credit line: Photographs in the Carol M. Highsmith Archive, Library of Congress, Prints and Photographs Division.
Carol M. Highsmith's photographs are in the public domain.

Marcus Smith posted two photos with the comment: "Steel Bridge, Portland. The original in 1888 and the 'new' one in 1912 for which we have Henry Pittock to thank I think. The 'new' photo is only 15 - 20 years old. Second ever bridge over the Willamette and first multi-vehicle bridge."
Doug Wedul *Waddell & Harrington, were the designers/engineers. Out of KC, MO. 1912.
Thom Small shared.


Beill Neill shared a NOLA Rails post
SP trein #2 the Cascade at Portland OR, 1964.
Norm Anderson You can see the tower of Portland Union Station through the girders of the bridge. Some of the passengers are already gathering their belongings, preparing to detrain.

Steven J. Brown posted
Amtrak Coast Starlight #11 crosses the Willamette River on the Steel Bridge in Portland, Oregon - December 31, 2016.

Marty Bernard posted this Flickr photo from an album of 11 photos in sequence
The power consist was 4302 (SD9), 4434 (SD9), 3873 (GP9), 3846 (GP9), and 4382 (SD9).

Drawing from HAER ORE,26-PORT,14- (sheet 1 of 3) from or0291
Drawing from HAER ORE,26-PORT,14- (sheet 2 of 3) from or0291
Drawing from HAER ORE,26-PORT,14- (sheet 3 of 3) from or0291

Railway Review, p138
[The sheaves for this bridge are 14' in diameter. Developing bearings that could hold the weight of the counterweights and half the spans was one of the major engineering issues Waddell had to solve when designing the lift bridge, for which he obtained the patents.]
Note how the approach trusses widened as they got near the shore of the river. This was to help accommodate the sharp curve the tracks had to make so that they could follow the shoreline of the river. This is the first time I have seen the sides of a truss span curve outward.

 [Bridge Engineering by J. A. L. Waddell, Digitized by Google, p732]

Charlie Easton posted
I think Steel Bridge in Portland is a worthy candidate for really awesome and fascinating railroad structures. While the lift bridge on my layout isn't a model, this bridge served as the inspiration. I needed a double deck rail bridge and this bridge had class 1 on the lower level and light rail and vehicular traffic on the top.
As I studied this I was amazed to discover that in the early 1900s when built, this bridge had some amazing design features, The lower deck can be raised independently of the upper deck for 72 vertical feet. Then for the really big ships, the whole thing can be lifted some 163 feet, Not bad for well over 100 years ago.
Dennis DeBruler The government has documented this bridge:

Historic Bridges had this reference of other Portland bridges included with this bridge. For now at least, I'm going to note it here.
or0316, this document has several more Portland bridge diagrams

While I'm using these notes as a placeholder for Portland bridges, here is another overview of the bridges on a T-shirt that my daughter bought me the year she was a coach at Oregon State University.
20190503 7975c
John Maggard posted two photos with the comment: "Portland, OR 2012...thanks for the add!"


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