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  • 17 Comments
Joined 1 year ago
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Cake day: June 25th, 2023

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  • Like:

    • It has that small-community feel still. I don’t see (perhaps because I stay out of a lot of the more tech-ey communities?) the kind of farming, low-effort, generally mediocre content I saw on Reddit.
    • Lack of the sense of a hyper-corporatized, “You’re only allowed to do things that make us money” sense that’s enshittified much of the internet lately. I’m not even sure if Lemmy can be monetized.

    Dislike:

    • Not yet large enough either. I don’t want hundreds of millions of users, but I still miss a lot of the more niche hobby/discussion communities I used to be able to participate in. Even communities for fairly large hobbies or interests can be dead on Lemmy.
    • The awful political takes. Everything from typical dumbness up to advocating violence (but it’s okay because it’s my point). And it’s everywhere.









  • Like the other comment says, concrete is rocks of various sizes (called “aggregate”) mixed with a cement and other additives to change its particular properties.

    The cement is the really important point, because once water is added to the cement, it undergoes a chemical reaction which hardens it. Saying cement “dries” isn’t quite correct - yes, it stops being wet, but some of the water actually ends up incorporated into the molecules of the final cement. This is also why cement is really hard to recycle - you have to undo that chemical reaction, as opposed to asphalt which stays the same material.

    Fun fact: When concrete is mixed at a big plant, it begins curing immediately. Concrete being carried in those big mixer trucks needs to be delivered before it cures in the truck!



  • Specifically talking about asphalt vs. concrete:

    • Asphalt is relatively cheap vs. concrete. This is partly because asphalt is a whole lot easier to recycle than concrete, which is almost un-recyclable, but also because asphalt is a relatively “simple” material - it’s mostly petroleum byproducts and gravel.

    • Concrete doesn’t grip very well, compared to the relatively textured surface of asphalt. Especially when wet! This is why you often see concrete formed with “ridges” or “bumps” cast into it. However…

    • This also makes concrete noisier and bumpier to drive over, making drivers less happy. It’s why it’s often used for short, low-speed uses like driveways, parking lots, or side streets.

    Just about the only thing concrete has going for it is it’s endurance, which it definitely wins handily.

    Every few years another engineered road solution is conceived - I’ve seen variations that would use glass which could be ‘re-fused’, concepts for recycling plastic waste, and many more. Most of these run into the issue that they’re either less ‘grippy’, or that they simply cost more even accounting for the longer lifespan.