The Canyonero of signals is surely this brawny Made in U.S.A. signal gantry mounted on top of the San Bruno grade separation. The gantry (probably a standard two-track gantry, to save money!) was too wide to be mounted in this location, so two cantilevered concrete platforms, seismically worthy, were built on each side to support the gantry and keep out any terrorists. [UPDATE: check out the engineering drawing!] If that wasn't enough, this signal gantry needed its signal house (probably a standard 8'x8' signal house, to save money!) perched on top of the opulent platform as well, with classy electrical conduits slung underneath and a dedicated ADA-compliant staircase allowing maintenance personnel ready access. Maybe they were trying to save some parking spaces by suspending everything, but the entire area had to be fenced in for security.
|East side, showing cantilever platform||West side, with signal house on cantilever platform||Under-hanging conduits connecting the signal heads to the relay shelter|
Oh, and the new speed limit at the San Bruno curve, the #1 worst curve on the entire peninsula? 65 mph, up from 60 mph before. It could have been 100 mph if this project had been conceived intelligently.
The concrete has been poured, and this installation shall now and forever stand as a monument to our Transit Industrial Complex, as it embarks on far more challenging endeavors such as electrification, level boarding, the downtown extension, and maybe some day high-speed rail. The symbolism is hard to avoid.
Clem, your point about the brain-damaged, short-sighted, misfeasance of Caltrain, in pouring a 65mi/hr speed limit into tens of millions of dollars of concrete, is well made.ReplyDelete
But.. how would you have done the signal gantry differently? To me, it screams out for reducing the bridge-truss by a segment (or changing the pitch), to allow the gantry to bolt to the existing overbridge. (If the overbridge can take the outriggers and gantry, it can take the gantry). And run the electrical conduit over the top of the bridge. And put the electrical cabinet at an end of the bridge; perhaps even (shock, horror) a custom electrical cabinet).
But is there room on the bridge for that? Is there room on the bridge for catenary masts? Is there room *under* the signal-gantry for catenary?
Did the staff at Caltrain think to ask these basic questions??
How would I have done it? I'm no expert, and that isn't even the point. All I can tell you is that this is clearly wrong.ReplyDelete
One thing - the train control house could have easily have been placed at grade, below the guideway. That's a simple start.Delete
Take a look at the signal gantries on the Berlin Stadtbahn. It serves both S-Bahn and intercity trains. The first mast is at about 1:05 in the video and many dozen more follow. The signal cabinets are much smaller, on the scale of traffic signal cabinets. I guess that means signalmen can't set up a table and take their lunches inside the cabinets during inclement weather.ReplyDelete
I see what looks like a graffit'ed signal-cabinet on the left at 00:59 and two on the right at 01:00. (guessing the smaller cabinet at 00:55 is a trackside phone?0Delete
I note that the signal gantries at 1:05 -- signals over both tracks, in both directions -- are actually two half-gantries. If you stop the video at 01:02, you can see the diagonal support for the right-side half-gantry. Due to the shadow, _I_ can't tell whether that's concrete, or a grey-painted steel beam or triangular plate.Given the age of the Berlin S-Bahn (there's a broader field-of-view at 00:57-00:58. Maybe I need a higher-res display than this old laptop.
I'll hazard a guess that it's a steel I-beam, cut at the bottom to be flat against a plate bolted into the foundations. But I'm not a civil engineer. It might be concrete.
Interesting to see the Ks-signal heads....
They shoot horses, don't they?ReplyDelete
If you can't point out anything that's wrong, you don't get to say "it's clearly wrong". That's called begging the question.
Where I come from it's called reading the blog post.Delete
where, exactly, do you see "scarce taxyayer dollars" being wasted? The marginal cost (per cubic yard) of the concrete you point out, looks miniscule. Exactly where is the money being wasted?
Note that "I dont like the design, it looks wasteful" is not actual evidence of waste.
Clem, I'm sorry to contact you via this method, but wanted to let you know that there's a forthcoming book with a unique take on California HSR. Details can be found here: www.tomzoellner.com. Again, sorry for the cheesy way of sending you a message via comments; I couldn't find an email address. Cheers and keep up the good watchdogging. TomReplyDelete
Is there some reason that wayside signals on simple posts are insufficient? It seems like a simpler solution.ReplyDelete
Gantry was chosen most likely to accommodate future 4-track expansion, of which another section would be added to the existing gantry so it would span 4 tracks.Delete
Ridiculous! Like Joey, I see no reason why a gantry is or was necessary.Delete
William: the gantry is going to have to be rebuilt for 4 tracks anyway.Delete
@Joey: Yes, the side opposite of the signal house will needed to be taken down, moved to the final 4-track location, and rebuild to span 4-tracks by inserting a new horizontal segment, but the half on the signal house side will likely see very little change.Delete
I fail to see any modular design which would allow half of it to be taken down while leaving the other half up. The support tower could remain, but the entire span structure is going to have to be replaced.Delete
@Joey, temporary support during the extension maybe, but far from complete replacement, with the construction most likely taken one overnight work period to complete. All signal gantry that Caltrain had built in recent years is of the same type and design, only differ in span width to suit the sites.Delete
It looks to me as if the clearances around the signal hut are designed to meet Caltrain's engineering standard for signals.ReplyDelete
See page 15 of SD-5000S.pdf, drawing SD-5109.
Other relevant Caltrain standards (I havent read them all yet)
Caltrain 2007 Engineering standards:
Caltrain Enginnering Standards, 2nd Ed. 2011:
Signal standards: http://www.caltrain.com/assets/_engineering/engineering-standards-2/Specs/Div18/Division18.pdf
Anyway... Richard M. would be right at home here. Caltrain has a Book. Caltrain contracted the work at San Bruno, and I bet the contract says the work has to be to Caltrain's Book.
The key issue is: who wrote the Book? Who has authority to ask for waivers in such cases? Who has the authority to grant waivers? If Clem is right, and the concrete "wings" were exorbitantly expensive, it's sure not in the contractor's interest to minimize cost.
According to the minutes of Caltrain's board meeting of March 20, 2013, bids for San Bruno came in below the Engineer's estimate:
Isn't $250 million of Caltrain-specific, Caltrain-unique, all-American, cardboard-compliant Advanced In-Cab Control and Signalling supposed to do away with the need for lineside automatic block signals all over the place?
I read of "getting rid of lineside signals" and "getting rid of cable ducts" as being selling points when other places talk about installing "Communications Based" (CB radio!) systems. So what's going on here?
Maybe the CBOSS signal sheds will need to be even larger and even more numerous than those needed everywhere today to house the Advanced CTC Electronics required to drive 24 color lights and two track circuits? (The naive might think that that amount of logic would fit in a device that required an electron microscope to examine ...) Perhaps multi-story? San Bruno's shed is more than half way there! Maybe the Communications Based cable ducts will be even larger than four inch diameter, and more numerous than San Bruno's meager pair, and even more galvanized than San Burno's? Maybe CBOSS radio antennas will be mounted on gantries even taller, wider, and more massive than the San Bruno LED Aspect Projection Super Support Uplift Facility. We can only dream!
Indeed. Maybe it's my unfamiliarity with American signaling practices, but why the need for multiple signals on a massive gantry?- it's not like San Bruno is some junction.Delete
@Anonymous who wries "CBOSS":Delete
No. Not $250 million of Cantrain-speciifc, Caltrain-unique, Advanced In-Cab Control and Signalling. A substantial chunk of the money is going to installing the base ITCS (from the very same contractors who brought us BART AATC). Another subsantial chunk goes to replacing all the communications and coded-track-circuits (yes, they're there) with replacements which can withstand interference from 25kV AC electrification.
Only part of the cost -- I don't recall well enough to guess, but maybe $100m? -- is for the special-to-Caltrain, Caltrain-unique, changes to ITCS to allow it to put crossing-barriers down n Menlo Park, behind a train which has passed through said barrier and is now stopped at the platform.
Of course, ITCS is unique to just Amtrak in Michigan, and Caltrain. Whoever thought the world needed yet another signalling system.......
@ Anonymous again:Delete
Perhaps the reason Caltrain still needs lineside signals, is for the freight trains that'll be running in their time-separated windows? Do FRA regs require lineside signals in territory where in-cab signalling and ATP are deployed and required?
"Do FRA regs require lineside signals in territory where in-cab signalling and ATP are deployed and required?"Delete
Nope. I think Metro-North and Amtrak still have 'em at "home signals" for interlockings, but apart from that, both have been allowed to just rip out all the other signals. I doubt the home signals are required either.
Seriously, most railroads are going to CAB SIGNALS everywhere except interlockings. (Where there are red lights for redundancy, just in case.)ReplyDelete
Caltrain has in-cab signalling. Surely Caltrain didn't install a new, two-track, bidirectional signal gantry, just for the three UP trains per day ?!Delete
Caltrain does not have in-cab signalling today. The engineer must view the signal aspect, call it out on the radio if it is restricting, and have it acknowledged by the conductor. Obeying the signal aspect (or not, heaven forbid) is entirely up to the engineer. It's very 19th century.Delete
What? you mean the !10-year-old CTC project was to install 19ith-century *line-side signals*? In the 21st century?Delete
Words fail me.
Anonymous, Richard Mlynarik, Clem, Kiwi, et al.........ReplyDelete
If CBOSS, Caltrain electrification costs, signal bridges, etc, etc, are “brain dead” “brain damaged, short sighted, misfeasance” “just plain wrong,” then why don't you bring this to the attention of NBC Bay Area 11? Or bring it up to the State Attorney General? The Civil Grand Jury? The GAO?
I saw a teaser on NBC Bay Area 11 this morning about Questionable accounting practice at Samtrans/Caltrain. The investigative report will air this evening Tue. Feb 11, 2014, on the late 11pm newscast after the Olympics. If NBC were to investigate CBOSS, electrification, etc, maybe you would see some action regarding your concerns, and the concerns would reach a wide ranging audience instead of the limited audience here.