• Portageville Bridge Replacement, Future Tier Traffic

  • Pertaining to all railroading subjects, past and present, in New York State.
Pertaining to all railroading subjects, past and present, in New York State.

Moderator: Otto Vondrak

  by 452 Card
 
Many "Thank Yous!" to John Kucko for the close-ups of the old structure. Those pics were exactly what I was hoping to see. Please keep us all updated if possible. Those workmen at the site are braving a harsh environment at this time of the year. I guess NS wants the old bridge gone ASAP to avoid any litigation or other trouble. Without trains on it, there is too much temptation for trespassers.
  by C2629
 
The new bridge has now been in use for four weeks. Has NS added any new trains for the route yet? If so what are the symbols ?🚂
  by SecaucusJunction
 
HA
  by Scott K
 
John Kucko's latest pic, Tie removal is well under way. Really makes "Old Shakey" look even more spindly.
Scott K.
Last edited by Scott K on Sat Jan 13, 2018 2:20 pm, edited 1 time in total.
  by pumpers
 
Great pictures. I don't quite know how to explain it technically, but the main "beams" of the old bridge (parallel to the rails) on which the ties sat were much farther apart than the rails - those are long ties! So it seems the ties would have had to provide vertical support for the load on the rails -and it looks like they were only supported themselves underneath several feet outside of the rails, and hence were susceptible to bending (breaking?) under heavy loads. Is that common on bridges? I think on the new bridge there is a "bed" with ballast directly under the ties, so they don't have to provide this extra support function, or far far less if the ballast directly under the rails compresses a little when the train goes over it.
  by TrainDetainer
 
Pumpers - you are correct about the old bridge. The timbers support all the track weight from the main beams/chords. Typically they are called timbers, not ties, because they are an active part of the bridge structure itself, not just part of the track. The old bridge is a bit wider than most in terms of timber span, and it is not only common but desirable to NOT have the track support beams directly under the rail. The wider support adds lateral stability to the track/live load and the flex of the timbers provides some cushion to the bridge structure from vertical pounding that could otherwise hammer a bridge to death in short order. Note the timbers are spaced very closely and are much larger than ties - I've heard of bridge timbers as large as 14" x 16", the size/spacing all calculated according to span, load requirements, wood species, etc. and breakage would only be due to age/deterioration or other problems.

The new bridge has a ballasted deck, meaning the continuous deck simply supports normal ballasted track where the track/ballast absorbs shock. Ballasted deck bridges also greatly reduce surfacing headaches at the approaches. Some people tend to think of ballasted deck bridges as a relatively new development, but they aren't. A relatively nearby example is Erie's Starrucca (1847).
  by Scott K
 
I hesitated to call the bridge timbers "ties", but did mainly because that's how they've been referred to most times by others. John Kucko said on his page that these weigh about 650 pounds each, and that there are "some 708 of them".

Scott K.
  by ctclark1
 
TrainDetainer wrote:The old bridge is a bit wider than most in terms of timber span,
No doubt due to the Erie's former gauge of 6'0, no? (I know this adds nothing to the conversation really, but an interesting piece of trivia about the history of the bridge)
  by pumpers
 
Thanks all, I figured there was a good reason for the long "timbers" -just didn't know what it was.
Since they were so critical, I wonder if they had to be replaced more often than ties. On the other hand, drainage under them due to fouled ballast was never an issue!
  by D Alex
 
ctclark1 wrote:
TrainDetainer wrote:The old bridge is a bit wider than most in terms of timber span,
No doubt due to the Erie's former gauge of 6'0, no? (I know this adds nothing to the conversation really, but an interesting piece of trivia about the history of the bridge)
No, by the time this bridge was built (1880's, if i remember correctly), the Erie had been gauged to standard gauge for some 20 years. Perhaps the previous bridge, but not this one.

I wonder if the bridge used to be 'gauntlet track'? That used to be fairly common on longer bridges.
  by Scott K
 
The engineering report linked to from this thread a while back, was, I think, where I read that the bridge was built for double track. I've never seen that anywhere else though. I did wonder if the deck would be wide enough for a second track, if they'd left off the railings and walkway gratings. Or maybe it did refer to a gauntlet track that was never installed.

Scott K.
  by TB Diamond
 
Correction to the above post by D Alex:

The iron Portageville bridge was completed in 1875.

In 1876 the Lehigh Valley Railroad paid the Erie almost one million dollars to lay 150 miles of third rail Elmira-Suspension Bridge, NY (a third rail had previously been put down Waverly-Elmira for use by the LVRR). The third rail to Buffalo was completed on May 22, 1876. The Lehigh Valley thereafter operated trains over the Erie Waverly-Buffalo with their own crews under trackage rights agreement. (Info in this paragraph from the book The Coming of the Railroad to Sayre by Richard Palmer)

Therefore yes, the Portageville bridge was originally built to 6 foot gauge.
  by D Alex
 
Scott K wrote:The engineering report linked to from this thread a while back, was, I think, where I read that the bridge was built for double track. I've never seen that anywhere else though. I did wonder if the deck would be wide enough for a second track, if they'd left off the railings and walkway gratings. Or maybe it did refer to a gauntlet track that was never installed.

Scott K.
I recently read about the Erie-Lackawanna railroad merger back around 1960, and their choice to use the Lackawanna mainline in western NY, at least partly because of the bottleneck posed by this bridge. Perhaps that was because of a lack of double track, or more likely because of speed restrictions over the bridge.

As for the gauging, yes, it seems Erie changed gauge between 1876 and 1880. I'd heard that Old Shakey was built in the mid 1880's, over a period of only 2 months. Depending on which build year is correct, it might've originally been 6'0" gauge, but dual-gaged, since Lehigh Valley had trackage rights at that time, and had laid a 3rd rail down. Erie it seems used both gauges for a time while transitioning, and a few years after Erie became standard, the LVRR built their own mainline.
  by pumpers
 
D Alex wrote: I recently read about the Erie-Lackawanna railroad merger back around 1960, and their choice to use the Lackawanna mainline in western NY, at least partly because of the bottleneck posed by this bridge. Perhaps that was because of a lack of double track, or more likely because of speed restrictions over the bridge.
I always thought it was the other way around - from Hoboken (Jersey City) to Binghamton the EL favored the DLW, but from Binghamton to Buffalo they picked the Erie. It could be that was Conrail and not EL making the decision on the first issue, but I am fairly sure the DLW was cut in western NY north of Wayland to about Groveland early in the EL days, the early 1960's already. The only route from Corning to Buffalo would have been on the Erie (and from BInghamton to Corning most of the DLW was gone by then already too - maybe already before EL as part of Erie-DLW "joint operations"). I guess going slow on the shaky bridge was the lesser of two evils, the other being the abandoned hill on the DLW which probably required pushers for freight, at least in one direction, and the mantra of EL was "save money".
EDIT: It could be the pushers on Dansville hill were only in the steam days. I've read that the Erie had more online industry, so that also may have killed the DLW west of Corning (or west of Binghamton as well).
  by TB Diamond
 
Construction of the iron Portageville bridge began on June 8, 1875 and was completed on July 31, 1875, not in 1880. Construction occurred account the original timber Portageville bridge had been destroyed by fire on May 6, 1875.

The bridge was six-foot gauge originally but dual gauged by May 22, 1876 per my post above.

The Erie completed laying a third rail Jersey City-Buffalo on December 30, 1878.

The Lehigh Vally Railroad completed its own line Sayre-Buffalo in 1892.
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