Rating:
5 votes

LSI - Dead River Bridge

Photos 

LS&I - Dead River Bridge

Photo taken by Josiah Hanna from flickr

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View this photo on Flickr

BH Photo #446526

Map 

Description 

Bridge features a functioning arch, supporting deck girders

Facts 

Overview
Steel arch bridge over Dead River on Lake Superior & Ishpeming Railroad
Location
Marquette County, Michigan
Status
Open to traffic
History
Built 1916
Builder
- Wisconsin Bridge & Iron Co. of Milwaukee, Wisconsin
Railroad
- Lake Superior & Ishpeming Railroad (LSI)
Design
Steel arch
Approximate latitude, longitude
+46.55443, -87.50721   (decimal degrees)
46°33'16" N, 87°30'26" W   (degrees°minutes'seconds")
Approximate UTM coordinates
16/461119/5155775 (zone/easting/northing)
Quadrangle map:
Negaunee
Inventory number
BH 67397 (Bridgehunter.com ID)

Update Log 

  • April 13, 2019: New photos from Luke
  • April 13, 2019: New photo from Geoff Hubbs

Sources 

Comments 

LSI - Dead River Bridge
Posted April 15, 2019, by John Marvig

I sometimes see these on similar viaducts and individual girder spans. I’ve heard them called “fishbellied” before Here’s an example on a short 50’ span:

http://bridgehunter.com/wi/eau-claire/bh84767/

Not yet sure on the history on that one, but it looks like it came from a larger viaduct. All spans on this branch line were moved from other places. Not sure why it would be on such a short span, as railroads routinely built even larger girders that were uniform depth. More examples:

http://bridgehunter.com/il/carroll/bh66537/

http://bridgehunter.com/mn/carver/bh53742/

LSI - Dead River Bridge
Posted April 15, 2019, by Clark Vance (cvance [at] dogmail [dot] com)

Unusual to see this design on a deck girder but it's not a normal bridge.

LSI - Dead River Bridge
Posted April 15, 2019, by Daniel

Given that every span is like that, I doubt it's due to reuse.

If the limiting factor is bending, adding depth to the section may be the most efficient means of adding strength (and at midspan, the limiting factor is bending). Think of how many trusses have a deeper section midspan.

LSI - Dead River Bridge
Posted April 15, 2019, by Clark Vance (cvance [at] dogmail [dot] com)

Also interesting is the girders with a shape like that of a turntable.

LSI - Dead River Bridge
Posted April 15, 2019, by Daniel

That sure is an unusual design.

I was thinking that it's odd that they don't have an upright above the center of the arch, rather than the deeper girder for the longer span, but I suppose that would significantly increase the loads in the arch.

LSI - Dead River Bridge
Posted April 13, 2019, by Tony Dillon (spansaver [at] hotmail [dot] com)

Well that's nifty!