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Joined 2 years ago
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Cake day: July 14th, 2023

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  • That’s not really the limiting factor for pyramids. If you were to build a shape of equal height, say a cube, then yes this would be the main issue.

    What are the failure modes for a pyramid?

    • A 45° pyramid can’t tip over since it’s center of mass is always sufficiently far enough from the bottom edge. So tipping isn’t one.
    • I’d say bending through cross winds is also not an issue for a pyramid unless you make it out of jello. So that’s also not a failure mode.
    • Crumbling of the bottom layers because of the weight of the top layers is definetly one.
    • Uneven foundation strength can cause the supporting area to be weaker in some spots more than in others, so that’s another failure mode.

    I’d say the crumbling and Foundation issues are heavily mitigated by 2 main factors.

    1st:

    The outer edge is always of height zero. As the pyramid grows in height it also gets wider, but the only point that is at risk of imminent collapse is the very center of the pyramid, since it is the only point that will reach a critical supporting mass first.
    Let’s say the pyramid reaches a height and the furthes block at the bottom in the center crumbles (let’s assume it actually turns into straight up dust). The clumbled block will still support some pressure but will also transfer it laterally into the adjacent blocks (essentialy like a liquid). Now the main question is “How many adjacent blocks does it need to support one crumbled block?”. If the answer is ≤1, than you have no problem, because with each new block in height, the pyramid also gets 1 block wider at each side. Similar to water pressure, the lateral force the blocks exhibit will increase linearly with height therefore never outpassing the increase in pyramid width. If it’s >1 than you will reach a point where the outer walls of the pyramid will start to collapse from inside pressure, and that will be your limiting factor for height.

    2nd:

    The blocks can be cemeted together, so whatever forces are being transfered laterally will not only be supported by the adjacent blocks, but also blocks adjacent to them and so on, and so on…
    Same thing goes for uneven foundation strength. The local decrease in support will be spread over a wider area because the blocks are merged together. Also Pyramids are usually not build block on block, but with a 50% offset, which will further aid to stabilize the structure.

    Usually, If you look at mathematical calculations for things like sky elevators the form to support the structure looks like a symmetric reciprocal function. This function actually requires way less material to support the weight of the center piece of the structure than a pyramid. So not only could a pyramid essentialy support itself until earths centrifugal forces take over, it would also be way too overkill in doing that.






  • I don’t know if that has been enshittified or was has always been shit in the first place but:

    Annotation Apps

    Seriously, how hard is it to make an app that let’s me make markups, use a stylus, and share that across devices.

    Exhibit A: Xodo
    It was once free, with all the good features, but then they took those features away and implemented a subscription model.

    Exhibit B: Drawboard PDF
    Once, came free with a Surface Pro or was a buy once use forever software, until Microsoft took a away all the bought licenses and locked most features behind a paid subscribtion.

    Exhibit C: Saber
    Its free. It doesn’t use Windows Ink. Why even bother?

    Exhibit D: Adobe Acrobat Reader
    Hahahahahahaahahaaaaaaaaaaahaaaa *Wheeze* hahahhhahaahahahaaaaa

    Exhibit E: Microsoft One Note
    Aneurism Simulator. You know how printing things suck because printers never play along? Microsoft decided to solve this problem by making printing out One Note sheets properly almost impossible on the software level. Also it can’t open PDFs properly or have normal A-Format pages. Either infinite drawing space or nothing.

    Exhibit F: Samsung Notes
    Actually decent. Free. Android Only. But at least it keeps the annotations separated from the PDF so you can still edit them after transfer. Good choice.