20th Century: (Bridge Hunter; Satellite, they removed the piers and abutments)
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| Steuben County Historical Society posted [Tropical Storm Agnes] As the rivers rose in 1972, someone figured that 15 loaded coal cars would help anchor the Penn Central Railroad bridge over the Chemung River -- you can see the results. Bringing down a structure of this size suggests the horrifying force of the waters, and damage such as this did in several railroads here in the northeast. We're looking northward here -- in the background we can see the Corning Glass Works office tower, and the Corning Glass Center/Corning Museum of Glass. Jim Kane: The Glass Museum had a "High Water Mark" way up high on the wall. Octagon Fad shared Fran Koch: seeing the downtown area firsthand after Agness........was so sad. And now, Corning has built a new facility in North Carolina. Tim Fuller: The purpose of putting loaded cars or locomotives on flooding bridges was to reduce the likelihood of damage from the lifting effect of the moving water. Any surface in a flowing medium has a lifting effect dependent on the density and speed of the flowing medium - think back to your childhood and putting your hand out the car window to play with the air slipstream. The major force keeping all bridges in place is gravity, so to counteract the lift forces of the moving river water, railroads routinely increased the weight on the bridge to increase the downward gravitational force. Boaz Miller: Tim Fuller, well, fluid dynamic lift requires the fluid above and below the surface, so the hand in the airstream doesn’t work here. It isn’t actually a lift; it is the tremendous shearing force due to fluid drag and lateral pressure on the support structures. Water is a very dense, heavy fluid and even a slow current can exert a massive shearing force against a stationary structure. Bob Mason: Boaz Miller you are correct. Additionally with that much flow there is often some major scour occurring. If the water scours out a big enough hole and undermines the pier or abutment, the piers will topple over unless they are anchored to a cement pile cap on driven piles. Bill Poole: The IHB does this frequently on the bridge over the DesPlaines River located @ McCook, Illinois. Dennis DeBruler There are several photos before and after it collapsed on this page: The after photos show a lot of debris against the trusses and the piers are tilted because of scouring and/or lateral pressure. The debris would magnify the lateral force of the flowing water against the truss. I found that link on this page: |
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| Art S. via BridgeHunter-19th |
NYC was the north/south route.
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| 1953 Corning Quadrangle @ 1:24,000 |
Another study in postcard colorization.
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| Via BridgeHunter-20th |
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| 1907 Postcard via BridgeHunter-20th |
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| RogerHamiltonPhotography |
Did the piers tilt because of scouring or because of the tremendous lateral forces exerted by the flowing water against the tree debris against the trusses? Or because of both?
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| RogerHamiltonPhotography |
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