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Nostalgia & History > Tunnels with more than two tracks?Date: 09/04/15 15:43 Tunnels with more than two tracks? Author: timz The Howard St tunnel in Baltimore and okay, we'll
say the Erie's Bergen Arches count as tunnels-- where else did three or four tracks fit into one tunnel? Date: 09/04/15 15:57 Re: Tunnels with more than two tracks? Author: pal77 Old Reading in Philly had 4 track subway. If you count the Bergen Arches as a tunnel then you could consider the Alemda trench.
Edited 1 time(s). Last edit at 09/04/15 16:55 by pal77. Date: 09/04/15 16:17 Re: Tunnels with more than two tracks? Author: Out_Of_Service pal77 Wrote:
------------------------------------------------------- > Old Reading in Philly had 4 track subway. I you > count the Bergen Arches as a tunnel then you could > consider the Alemda trench. are you referring to the City Branch from Broad St to Park ??? PRR/PC/CR/SEPTA suburban station had/have 4 tracks that went into Suburban Station ... there is now a 4 track curved tunnel, that belongs to Septa, under center city Philly that connects the former PRR and former Reading passenger main lines the east river tunnels in NYC have 4 tracks north out of Penn Station but all 4 tracks are not in one bore ... Date: 09/04/15 16:38 Re: Tunnels with more than two tracks? Author: rschonfelder I highly doubt a 3 or 4 track tunnel would exist except on someone's layout. I distinguish a tunnel from a subway with the latter being an excavation with something then built on top eg. a station or building. A proper bore through natural geologic strata requires a large arch for strength and support. This makes the bore far larger and the excavation volume is too great. It is far easier for them to do multiple tunnels side by side like one can see on the D&RGW Utah (Soldier Pass) or some of the famous locations in the east eg. Detroit River. The smaller the bore, the greater the strength with a reduction in the possibility for collapse.
This is not to say there are not double track tunnels but I would like anyone to put up a photo of a 3 or 4 track bore through natural strata. I do not know of any in the world. As an example, when the CPR built the Connaught Tunnel under the Roger's Pass in 1916, it was built as double track for the vehicles of the time. Naturally, they were lower freight cars. With the advancement of Autoracks, clearances in this tunnel were not made greater but rather the double track removed and the single track centred under the crown of the arch through the length of the tunnel. Excavation of this bore would have been very costly and likely jeopardise the structure even by excavating down. In more recent times, we can see the advancement of larger tunnels being excavated which are not tubular. Many roadways are made 3 lanes wide for each direction with safety lanes at the side. Such excavations are very expensive and have their own challenges (eg. water sepage). We have several here in Melbourne and all were built using private funding therefore are revenue raising. A railroad would not likely do a similar tunnel simply because of need vs. cost. Note, I did not say "never" but that is my take on this. Rick Date: 09/04/15 16:54 Re: Tunnels with more than two tracks? Author: pal77 Out_Of_Service Wrote:
> > are you referring to the City Branch from Broad St > to Park ??? Yes and I only know about it from recent article in Railpace, showing photos of the subway. Date: 09/04/15 18:03 Re: Tunnels with more than two tracks? Author: Lackawanna484 How many tracks in the New York Central / MetroNorth tunnel between GCT and 92nd street
Date: 09/04/15 19:14 Re: Tunnels with more than two tracks? Author: CPR_4000 Lackawanna484 Wrote:
------------------------------------------------------- > How many tracks in the New York Central / > MetroNorth tunnel between GCT and 92nd street Isn't that more of a covered cut than an actual tunnel? Date: 09/05/15 11:44 Re: Tunnels with more than two tracks? Author: ns2557 I should know the answer to this but, How many Tracks was the Pennsy's Main thru Spruce Creek Pa? Ben
Date: 09/05/15 11:58 Re: Tunnels with more than two tracks? Author: RuleG ns2557 Wrote:
------------------------------------------------------- > I should know the answer to this but, How many > Tracks was the Pennsy's Main thru Spruce Creek Pa? > Ben At Spruce Creek, the Pennsylvania Railroad built two tunnels which each accommodated two tracks. Date: 09/05/15 12:45 Re: Tunnels with more than two tracks? Author: pmack Stop this video at 1:13. There is a portal with three tracks but it quickly becomes one track inside the tunnel. http://www.arctictrains.com/Video-test/i-v8KbqsJ/A
The amazing model rendition of the scene can be seen part way down on this page. It is the snowy scenes: http://www.arctictrains.com/In-Model/i-jrL6CpT Date: 09/05/15 21:53 Re: Tunnels with more than two tracks? Author: emd_mrs1 The CSX tunnel at Harpers Ferry is 2-track but one end is a little wider because of a switch inside the end of the tunnel for a diverging line.
Does that count? Michael |