Gregory's Server
@kegill @farbenstau I've only seen them used in light rail systems in the US
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23 comments
@farbenstau (when relating to trains this a problem exclusive to communist/east german made concrete. Subpar materials used ) @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. https://www.sueddeutsche.de/bayern/zugunglueck-garmisch-partenkirchen-unfall-fuenf-tote-ermittlungen-bahn-mitarbeiter-1.6244651 Do you have any evidence explicitly linking this to Concrete Cancer? @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. @farbenstau 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. @freemin7 It seems they were from the new Bundesländer, indeed. @farbenstau 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). @freemin7 I wonder if the Schienenfreunde Cartel was only about steel or also about sleepers … Als alkaliempfindlich gelten Gesteine, die amorphe oder feinkristalline Silicate enthalten, wie z. B. Opalsandstein und poröser Flint. Insbesondere die in Norddeutschland in größeren Mengen vorkommenden Opalsandsteine sowie die Grauwackevorkommen in der Lausitz können schädliche Mengen an alkalilöslicher Kieselsäure enthalten. Durch Verwendung von Zementen mit niedrig wirksamem Alkaligehalt (mit „(na)“ hinter der Normbezeichnung gekennzeichnet) @farbenstau @farbenstau The question is: 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. 🤷 @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. @farbenstau  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. @SuperMoosie @aeva @kegill 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 ... @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 … |
@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", https://en.m.wikipedia.org/wiki/Alkali%E2%80%93silica_reaction