Passenger Trains > "Plugging" subway and rail tunnels

The NY Times has an article today about testing of an inflatable balloon to block water from flowing into a railroad or subway tunnel. Using a Department of Homeland Security grant, West Virginia University has constructed a series of mock subway tunnels to test various barriers.

The current plan is testing Vectran, a woven polymer used in space suits, Mars landers, etc. Early versions failed when the enormous pressure of water split the balloon. The current version uses a triple layer model, similar to radial tires. Versions of this balloon are used in long European tunnels to cut off smoke, air, etc when required.

New York City lost 14 subway and several roadway tunnels to flooding, as well as several Amtrak and PATH tunnels. The WVU test is using a mock subway tunnel to test various flows of water. The pressur of water building up behind the tunnel has been a huge problem, as early versions have split, and man tunnels lack the clean smooth sides essential to getting a tight fit. The roadway tunnels are even more complex due to their much larger apertures.

DHS recognizes that sealing a rail tunnel will be more complicated than the prototype. Third rails, overhead catenary, safety walkways, pipes, standpipes, signals, etc all reduce the tight fit essential for the plug to work. It's likely that the point of installation will probably be modified to reduce the additional elements. LIRR, for example, built an in-ground contact point under the tracks for bolting down its low level barrier structure at West Side yards



http://www.nytimes.com/2012/11/20/science/creating-a-balloonlike-plug-to-hold-back-floodwaters.html

A giant can of insulating foam should do the trick.....

CPRR Wrote:
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> A giant can of insulating foam should do the
> trick.....

I wouldn't want to be anywhere near when water pressure blasts that marshmallow through the tunnel, though....

The project is seeking a fairly rapid, inflatable solution, and seems to avoid the tried and true "flood gates" found in places like Louisville KY. PATH actually built a wall at Exchange Place station in 201 (edited) to prevent fire suppression water from the World Trade Center (fire) from entering the deep station on the NJ side.



Edited 1 time(s). Last edit at 11/20/12 13:53 by Lackawanna484.

Lackawanna484 Wrote:
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> CPRR Wrote:
> --------------------------------------------------
> -----
> > A giant can of insulating foam should do the
> > trick.....
>
> I wouldn't want to be anywhere near when water
> pressure blasts that marshmallow through the
> tunnel, though....
>
> The project is seeking a fairly rapid, inflatable
> solution, and seems to avoid the tried and true
> "flood gates" found in places like Louisville KY.
> PATH actually built a wall at Exchange Place
> station in 2011 to prevent fire suppression water
> from the World Trade Center from entering the deep
> station on the NJ side.


It wasnt only fire supression water they also feared the WTC foundation walls collapsing and letting the Hudson flow right on in effectively flooding the whole path system. 2001 btw figure you fat fingered.

Reminds me of the episode of Seinfeld where Kramerica Industries creates the oil bladder for tanker ships.... This sounds like a Kramerica Industries invention.

rovertrain Wrote:
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> Reminds me of the episode of Seinfeld where
> Kramerica Industries creates the oil bladder for
> tanker ships.... This sounds like a Kramerica
> Industries invention.

"You want to play dirty...well there is nothing dirtier than a gaint ball of oil"

Doesn't sound like a logical solution. If you stop a water leak under a pressure
head at one location it will often divert to the next weakest point and all you do
is move the leak. This would seem especially true for an old tunnel not designed
to be continuously submerged as is the case with river crossings, etc.

Ernst Stavros would probably have a steel door in place in a few minutes. "Q" would probably have a quick efficient fix too!