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Stefan Baur 6 * πŸ’‰

@sidereal This all sounds nice in theory. But due to Murphy's Law, attempting to pull this off with this particular make and model of tram wil lead to the tram toppling over, disintegrating violently, crushing and killing all of its passengers as well as killing all the people on the tracks with flying sharp-edged, high-velocity debris.

53 comments
SuperMoosie

@farbenstau

Casual wiring harness assembler ->Electrical engineering -> computer repairs -> customer service/logistics/remote diagnosis -> interal sales-> change management/support/project management to some extent.

Currently working on a job that automatically changes points based on a trams destination, with a manual override buttons in cab.

Stefan Baur 6 * πŸ’‰

@SuperMoosie Well, at least we're past the times where the only in-cab mechanism to operate the switch/point was passing a particular section under power vs. coasting through it.

Kathy E. Gill πŸ‡ΊπŸ‡¦

@SuperMoosie @farbenstau

Grateful for both of your posts should the undergraduate engineering students in my tech communication/engineering ethics class ever offer this one. (No one ever has.)

@sidereal

Stefan Baur 6 * πŸ’‰

@kegill @SuperMoosie @sidereal I can actually speak from personal experience that you absolutely don't want to be anywhere near that switch/point when somebody tries that on a track with concrete sleepers and a diesel locomotive weighing 80 metric tons. Even though its center of gravity was low enough that it didn't topple over. (I was neither aboard the loco nor in the switchbox, but I was close enough to get hit by the dust cloud when it cracked all the sleepers …)

Kathy E. Gill πŸ‡ΊπŸ‡¦

@farbenstau

β€œConcrete sleepers” was a bit of foreign language. I had no idea.

Added: the US doesn’t use its limited trains enough to cost justify leaving wood behind.

Stefan Baur 6 * πŸ’‰

@kegill Here's proof of the incident. Fella on the bottom left was a teammate of mine, fella in black crossing the track was my engineer, on his way back from checking how his colleague on the derailed locomotive was doing (turns out he was fine).

Stefan Baur 6 * πŸ’‰

@kegill Must have been around 2012-2013, Ulm, Germany, in the shunting yard south of the roundhouse(s)*. Affected loco is a German Rail class 218.

*three back then, but two have since been torn down

Stefan Baur 6 * πŸ’‰

@kegill This picture also shows that it requires quite a bit of skill and proper timing if you want to let the loco go both ways until it locks up. Merely eyeballing it will result in a situation like in this incident more often than not. Also, shunting operations are limited to a Vmax of 25 km/h. Could have ended worse at higher speeds …

DELETED

@kegill @farbenstau
In Japan where I live now, all the sleepers are concrete. In the USA where I grew up sleepers are called railroad ties. I didn't hear the word sleeper in reference to rail until I worked with an Italian who was raised in London.

Daigoro Toyama

@farbenstau @KawaTora @kegill Japan must have imported a lot of terms associated with railways from the UK. They call switches γƒγ‚€γƒ³γƒˆ (literally "points") in Japanese. Sleepers are ζž•ζœ¨ ("pillow wood"), which I'd imagine was coined based on the UK term.

Stefan Baur 6 * πŸ’‰

@kegill For some real foreign language, try "HilfsblΓ€ser" and "Luftpresser". To the uninitiated, these sound like German profanities, but these actually the proper nouns for two particular (steam) locomotive components.

aeva

@kegill @farbenstau I've only seen them used in light rail systems in the US

Stefan Baur 6 * πŸ’‰

@aeva @kegill Germany uses them a lot … and has had quite some nasty surprises with them. Turns out derailing locos aren't the only way to cause fatal structural damage to them.

cf. "Concrete Csncer", en.m.wikipedia.org/wiki/Alkali

Johann-Tobias SchΓ€g

@farbenstau (when relating to trains this a problem exclusive to communist/east german made concrete. Subpar materials used )

Johann-Tobias SchΓ€g

@farbenstau Bzzt source cited does not collaborate claim:
web.archive.org/web/2023060111 does refer to them having damages not defects. Accodring to local press a previous conductor on the same line the day before reported a visual anomaly. br.de/nachrichten/bayern/beric

This kinda all points against a link to Concrete Cancer unless you got newer German primary sources you are likely wrong IMHO.

Also no legal proceedings were started again the company which made the damaged part, this further speaks against

@farbenstau Bzzt source cited does not collaborate claim:
web.archive.org/web/2023060111 does refer to them having damages not defects. Accodring to local press a previous conductor on the same line the day before reported a visual anomaly. br.de/nachrichten/bayern/beric

Johann-Tobias SchΓ€g replied to Johann-Tobias

@farbenstau a systematic error (bad chemistry). While there is reporting of special inspection where many of this type were replaced this isn't phrased in a way that suggest a type wide issue. sueddeutsche.de/bayern/zugungl

Do you have any evidence explicitly linking this to Concrete Cancer?

Stefan Baur 6 * πŸ’‰ replied to Johann-Tobias

@freemin7 I found an older, but post-reunification case: Hamburg-Berlin. Concrete sleepers from the 1990ies failed around 2008, track had to be closed off for 3 months for the replacements to be installed.

Johann-Tobias SchΓ€g replied to Stefan Baur 6 * πŸ’‰

@farbenstau
Interesting. Now the smoking gun question:

Were the concrete sleepers manufactured in (former) east germany?

Maybe i should have used a weaker statement and called it a non-west german problem.

Stefan Baur 6 * πŸ’‰ replied to Johann-Tobias

@freemin7 It seems they were from the new BundeslΓ€nder, indeed.

Johann-Tobias SchΓ€g replied to Stefan Baur 6 * πŸ’‰

@farbenstau
Let's call it a communist Altlast then.

I found nothing about concrete cancer being a problem before east germany in that region. (looked from Nazi germany to Prussia)

That this issue plagued east germany trhough outs it's existence suggests some geological cause with a lack of process control and competition. That the problem persistent so long into the unified germany also shows a market failuire, possibly due to local monopoly and limited west german competition (distance).

Stefan Baur 6 * πŸ’‰ replied to Johann-Tobias

@freemin7 I wonder if the Schienenfreunde Cartel was only about steel or also about sleepers …

Johann-Tobias SchΓ€g replied to Stefan Baur 6 * πŸ’‰

@farbenstau
It seems that was about the total price of the rail.
The limited competition i alluded to is just a "it cost money to transport things over long distances"-thing in my mind. Building one concrete industry isn't a problem but if there is a cheap local supplier producing subpar goods which become subpar after 2 decades, that's a hard market to disrupt.

BTW, it totally was a geographical issues combined with bad procress control according to the german wikipedia:

@farbenstau
It seems that was about the total price of the rail.
The limited competition i alluded to is just a "it cost money to transport things over long distances"-thing in my mind. Building one concrete industry isn't a problem but if there is a cheap local supplier producing subpar goods which become subpar after 2 decades, that's a hard market to disrupt.

Johann-Tobias SchΓ€g replied to Johann-Tobias

@farbenstau

Als alkaliempfindlich gelten Gesteine, die amorphe oder feinkristalline Silicate enthalten, wie z. B. Opalsandstein und porΓΆser Flint. Insbesondere die in Norddeutschland in grâßeren Mengen vorkommenden Opalsandsteine sowie die Grauwackevorkommen in der Lausitz kΓΆnnen schΓ€dliche Mengen an alkalilΓΆslicher KieselsΓ€ure enthalten. Durch Verwendung von Zementen mit niedrig wirksamem Alkaligehalt (mit β€ž(na)β€œ hinter der Normbezeichnung gekennzeichnet)

Johann-Tobias SchΓ€g replied to Johann-Tobias

@farbenstau
und durch Begrenzung des Zementgehaltes im Beton kann bei Verwendung von BetonzuschlΓ€gen mit alkaliempfindlichen Bestandteilen die Alkalireaktion meist vermieden werden.

Johann-Tobias SchΓ€g replied to Stefan Baur 6 * πŸ’‰

@farbenstau The question is:
Does "meist" become always when it's done properly and it's a failuire to do properly causing the meist?
Or is it always random?

I think the concrentation of such defects in particular orders for particular installation kinda speaks against a truely random "meist"? However in east germany "concrete cancer" also impacted some "Plattenbau"s but also in local clusters. 🀷

Stefan Baur 6 * πŸ’‰ replied to Johann-Tobias

@freemin7 To me, it sounds like you cannot rule it out completely, either due to the source material being too heterogenous in nature, or due to factors that are not completely known/understood yet. So you need rigid quality control, both during manufacturing and at regular intervals once the sleepers are in place.

Johann-Tobias SchΓ€g replied to Johann-Tobias

@farbenstau
But i was wrong about it just being process control. Fixing it requires a significiant amount of different material which is non local or more expensive. Lack of process control + cheapening out.

SuperMoosie

@farbenstau @aeva @kegill

There was a company trying to sell hemp sleepers. Negative co2. Income for farmers, kept rail cooler, put a wireless mesh sensor in it so condition could be monitored remotely.

thewest.com.au/business/agricu

Stefan Baur 6 * πŸ’‰

@SuperMoosie @aeva @kegill
Looks like the sleepers are not made from hemp, but from steel. The track ballast is replaced with hemp, though.

Oh dear. We already have issues with criminals stealing the wiring that's running parallel to the tracks, due to the copper. Now add hemp to the equation ...
youtube.com/watch?v=WeYsTmIzjk

Stefan Baur 6 * πŸ’‰ replied to Kathy E. Gill πŸ‡ΊπŸ‡¦

@kegill That's what you and I know, but some pothead might not … we've had copper thieves rip out glass fiber because they couldn't tell the difference …

Galbinus Caeli 🌯

@kegill @farbenstau I'm pretty sure the CalTrain tracks 200 meters from my house are on concrete sleepers.

Kathy E. Gill πŸ‡ΊπŸ‡¦

@SkipHuffman

That makes sense as they are highly used passenger trains. Most of our (limited relative to Europe or Asia) rail use nationwide is for freight, however.

@farbenstau

Galbinus Caeli 🌯

@kegill @farbenstau yeah, there is no more than one one freight train a day on those tracks. It's almost entirely commuter rail. ( I live between San Jose and San Francisco)

anyMouse

@SuperMoosie @farbenstau @sidereal Few years in Brno, a tram driver activated a switch when previous tram was still not past it entirely and at least one person got killed

Chris Real

@farbenstau @sidereal

Once again, theory disproves what practice has verified.

I hear you guys are still trying to figure out how houseflies can fly.

I guess, in the meantime they can't.

Excuse me while I go get my flyswatter.

(I guess you didn't read all the related posts.)

Stefan Baur 6 * πŸ’‰

@_chris_real @sidereal Murphy's Law doesn't become invalid only because you have n examples of where it worked just fine.
Do it to rob a train, it will work. Do it in a controlled test environment to prove a point, it will work. Do it to actually save someone's life, and it will fail in the most spectacular way you can imagine. Either just because of a random streak of misfortune or because there's some subtle detail that was different this time and that you missed during the execution of your plan. That's what Murphy's Law is all about.

@_chris_real @sidereal Murphy's Law doesn't become invalid only because you have n examples of where it worked just fine.
Do it to rob a train, it will work. Do it in a controlled test environment to prove a point, it will work. Do it to actually save someone's life, and it will fail in the most spectacular way you can imagine. Either just because of a random streak of misfortune or because there's some subtle detail that was different this time and that you missed during the execution of your plan....

Chris Real

@farbenstau @sidereal

You just explained to me that a law is how things work, except that sometimes it doesn't work.

There, I simplified it for you.

Let's not go any furtherβ€”you'll just be trying to save face, by obfuscating caveats and qualified conditionals.

And I don't care.

SuperMoosie

@farbenstau

An out of control trolley car implies speed.

You won't be able to get the timing right between the two wheel sets or be able to complete the lever flip in between the front and back wheel, if it is at speed.

@_chris_real @sidereal

hugovangalen πŸ€– πŸ•ΉοΈ 😼

@farbenstau Yes, exactly this!

By introducing the possibility of the driver getting killed, or not, this all feels more like an elaborate SchrΓΆdingers Cat than a solution to the trolley problem.

@sidereal

bakkus

@farbenstau @sidereal See: every episode of "Well, there's your problem"

Pascal

@farbenstau @sidereal
I mean this what happens when you do it at 200km/h.

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