• sp3ctr4l@lemmy.zip
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    15 days ago

    Pouring a good amount of sugar into an ICE vehicle’s gas tank will also … uh… give that car a … tummy ache.

    EDIT: Water is more effective, and sand even more so.

      • skillissuer@discuss.tchncs.de
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        13 days ago

        if you can get into fuel tank you can do so many more interesting things. chlorinated solvents will burn giving hydrogen chloride, and this will corrode everything downstream, pretty fast at that because it’s hot

        also if you can fuck with fuel tank, you might be able to do the same with engine oil. fine alumina or silica added to it will cause quick weardown of moving parts that at the same time looks natural

        not sure what kind of (permanent) damage water will do to engine, maybe it’ll look like it’s flooded if enough gets in

      • sp3ctr4l@lemmy.zip
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        15 days ago

        AFAIK, the whole point of adding sugar and sand to a gas tank is that they clog up the filters, and that can result in the in the engine stalling… after an indeterminate amount of time.

        The idea being if you can add enough, stealthily, now the car fails without an immediately apparent time-proximal cause.

        Do that to an entire motor pool, or a good chunk of it, and you can functionally force a decision between a significant amount of logistics and repair costs, and fleet downtime… or, deal with a random number of vehicles failing randomly.

        Sand is… probably better at clogging up fuel pump filters faster than sugar, and if any actually gets into the actual engine, can cause more damage there.

        Water, on the other hand, is more likely to rapidly cause an ICE vehicle to either sputter or stall… but you have to use a good bit more water than sand or sugar.

        Anyway, back to my jam.

  • LovableSidekick@lemmy.world
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    15 days ago

    2 lbs of sugar would fit in two Venti size drink cups.

    1 ton of concrete wouldn’t fill up a VW beetle.

    So if you want to sabotage even a small office building, you’re gonna need a fuckload of sugar.

  • Onno (VK6FLAB)@lemmy.radio
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    14 days ago

    I’m not a concrete expert, but a tonne of concrete is less than half a cubic metre.

    A concrete truck carries 10 cubic yards, or nearly 18 metric tons of concrete.

    If this “educational fact” is true, then that amount of sugar might cause an issue with a piece of sidewalk, but it’s unlikely to get noticed on anything being built with concrete, unless you bring a metric shit ton of sugar to the party.

    As it happens, sugar appears to be added to concrete on purpose, specifically to increase the working time at the potential cost of weakening the structure, but research into that is ongoing.

    Source: https://concretecaptain.com/what-does-sugar-do-to-concrete-mix/

    In other words, this post is bollocks.

    Edit: After it was pointed out to me by @[email protected] that my link was slop, which I agree after reading more than the first two paragraphs, I went looking for better information and found this actual research:

    https://www.sciencedirect.com/science/article/pii/S221450952030036X

    Interestingly during my search for information in relation to sugar added to concrete, my results appeared overwhelmingly generated by LLM, like the top link I found initially.

    Also, adding sugar appears to increase the compressive strength and that might be more significant than the increased work time.

    • Lupus@feddit.org
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      15 days ago

      In other words, this post is bollocks.

      I don’t know, after reading through that AI slob of an article it says a good amount to add while still retaining sufficient strength after curing is between 0,1 to 0,5% sugar.

      So let’s assume that more than 1% gets you into trouble, that’s still a lot, but sticking to your 18 tons concrete truck example - 180kg of sugar will ruin a whole truckload of concrete.

      I think I could smuggle 180kg of sugar into a concrete truck without anyone noticing until it’s too late.

      I’d say with enough people and dedication the story in the post could be true, not super likely but also not impossible.

      • evasive_chimpanzee@lemmy.world
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        15 days ago

        There’s two broad categories of ways that concrete can get messed up: things that apparently ruin a batch on the spot, and things that compromise the resulting structural integrity in ways that might not be readily apparent.

        The biggest things I can think of for the first category are water and time. More water means more “workability”, so it flows better, but it means the overall strength goes down. You basically want to use a minimal amount of water you can get away with. More water also means more time to set, so concrete workers will add water to the mix in the truck to slow it down if they need to. You can always add more water, but you can never take water out (or add more cement/aggregate on site). Concrete trucks have a water tank on board to add water, and also clean off equipment after pours because job sites often don’t have water. If enough water is added to the concrete in the truck, the batch is ruined. I’m sure there are compounds that could ruin a batch, but the water is right there.

        Time also hurts because there is a ticking clock for getting the mix out of the truck once it has been made, particularly if the batch plant is far from the work site, and weather is hot. If the site is not completely prepped and ready to go when the truck gets there, enough delays will force the whole batch to be scapped before it ruins the truck. A lot of work goes into getting forms set properly and squared, and the underlying gravel compacted, so that is all delicate before the truck gets there.

        The second category, things that compromise the integrity over time has a lot of potential, but there is no guarantee that strength will be compromised enough to cause failure, and there’s a lot of potential for collateral damage if it’s in a bridge, building, or something people could be on/in. The first things that come to mind here are stuff that will decay over time resulting in voids, like woodchips. I know there’s been research into woodchips as an intentional additive, but I’m sure there’s more science that goes into that than just tossing it it. Something that causes oxide jacking would also really increase failure rates. This is when a material like steel rusts and expands, splitting concrete apart. This happens often if rebar is not fully encased in concrete. This does happen eventually to any reinforced concrete, which is why modern concrete structures have design lifetimes unlike Roman concrete which lasts indefinitely, but has to be much more massive. Adding a bunch of nails or something like that to concrete would probably speed up the process, but enough nails/woodchips to make a difference would most likely be noticed by the people doing the pour (which could actually be a benefit).

        If you wanted it to be unnoticeable, you would probably want to get a roll of rebar tying wire, and figure out a way to get it placed in the prepped site in such a way that it would be exposed to the elements after the final pour without being easily noticeable by the people doing the pour. Bonus points if the effort is focused on areas of stress concentration like corners or joints in the concrete.

      • towerful@programming.dev
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        15 days ago

        Not a concrete expert, but dead bodies. They decompose, can create pockets of pressurised gas, and leave a hollow cavity of no structural strength.

        Source: Me. I made it up, but seems plausible.