Passenger Trains > NBC I-Team Report On NJ High-Speed Catenary Project

Project is over budget and behind schedule. Scheduled to open last month, now scheduled to open in November 2018. http://www.nbcnewyork.com/investigations/Amtrak-Construction-Project-Delays-New-York-Penn-Station-Investigation-435625963.html

Here's the link to the Inspector General's report from 2015 on the project. https://www.amtrakoig.gov/sites/default/files/reports/oig-a-2015-012.pdf

So back in the day this very section of track had a test segment of constant tension catenary installed that made use of the existing catenary structure. Then as soon as the Feds were paying Amtrak went all in for brand new cat structure, with a reduced distance between catenary supports. The whole thing is way overbuilt with even the guy supports getting full concrete foundations. I know why Amtrak would want to get the newest hardware, even if the older stuff could be rehabilitated, but that still represents a failure of the government funded infrastructure process.

mbrotzman Wrote:
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> So back in the day this very section of track had
> a test segment of constant tension catenary
> installed that made use of the existing catenary
> structure. Then as soon as the Feds were paying
> Amtrak went all in for brand new cat structure,
> with a reduced distance between catenary supports.
> The whole thing is way overbuilt with even the
> guy supports getting full concrete foundations. I
> know why Amtrak would want to get the newest
> hardware, even if the older stuff could be
> rehabilitated, but that still represents a failure
> of the government funded infrastructure process.

The project also includes re-spacing of track centers. This isn't just a quick re-stringing of wire on the existing cat structures.

mbrotzman Wrote:
-------------------------------------------------------
> So back in the day this very section of track had
> a test segment of constant tension catenary
> installed that made use of the existing catenary
> structure. Then as soon as the Feds were paying
> Amtrak went all in for brand new cat structure,
> with a reduced distance between catenary supports.
> The whole thing is way overbuilt with even the
> guy supports getting full concrete foundations. I
> know why Amtrak would want to get the newest
> hardware, even if the older stuff could be
> rehabilitated, but that still represents a failure
> of the government funded infrastructure process.

The catenary support spacing is dictated by the proposed speed. 150 or 160 mph service will not work long-term with the old PRR spacing due to the dynamics of the pantograph to catenary contact. There will be waves and jumping that will sooner or later cause major issues. A test track is one thing. The catenary can be fine-tuned to permit short-term testing at high speed. For everyday high-speed operation, shorter spans than existing are needed.

The guy anchors are a classic case of what you can see and what you can’t see. The old PRR anchors above ground look like a simple rod encased in a grouted pipe going into the ground. What you can’t see with the old anchors is that guy rod attached to a reinforced concrete-encased steel structure about ten feet underground. It's what structural types call a “dead man” anchor. The new style guy anchor – a reinforced concrete drilled pier with an embedded steel T for attaching the guy – is much easier and cheaper to construct than those old PRR designs. The guy loads are significant. Some are rated for 120,000 pounds breaking load. The anchor, whichever type is used, must be hefty.

bioyans Wrote:
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> The project also includes re-spacing of track
> centers. This isn't just a quick re-stringing of
> wire on the existing cat structures.

Wrong. Respacing the track centers was rejected out of hand very early in the project because of how impractical it made the schedule. Same with curve easements of the 4 curves in this segment. The tracks are staying right where they were except at Midway interlocking where the switches are moving about slightly.

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Back in 1965, LTK Engineering noted placing intermediate structures at ~150 ft spacing from existing was required for 150 mph speeds.

In this segment, Amtrak also tried to acknowledge that due to its lack of maintenance of the foundation concrete and steel paint, the existing poles are at the end of their useful life and need to be replaced, many having degraded significantly down at their base. That is part of why a design was made using completely new poles. The other thing the new design allowed was changing to individually registered constant tension catenary instead of the long run fixed termination catenary in current use.

You have to recall when PRR electrified with their own money they came up with the cheapest system for their 80 mph speeds, not a robust system for 160 mph speeds. The cheapest system involved very long spans, inclined catenary on curves to avoid additional poles, wire cross-spans between poles instead of k-frame trusses, and joint use of cross beams for signals and catenary, with signal bridges serving as the tension points of the catenary (the top messenger wire was always fastened against the robust dual catenary/signal bridges).

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