I'm always fascinated by how they can excavate that deep and the sides do not collapse
this post was submitted on 21 Apr 2025
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Engineering
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Mining engineers calculate how the walls and paths need to be sloped, shored up, and shaped to prevent collapse. This channel on YouTube has a lot of good content about stuff like this, but this video is about hole collapses and how they're prevented. Reminds me of the old engineering adage- "anyone can build a bridge, but it takes an engineer to just barely build a bridge." Same goes for anything we do. You can do a lot by over-building and just accepting inefficiencies, but in a case like this you want to excavate as much of the ground as possible so you want the slopes to be as steep as possible. Anyone can dig a stable hole that's like a pyramid where the slopes are very shallow, but engineers find exactly how steep you can safely get away with.
A toolgif on Lemmy? Hurray!
I try to pick from a variety of sources, but it's tempting to make this community nothing but toolgif reposts for a few weeks. There are so many cool things to share.
They usually bring full tankers of ANFO in to fill holes this big.
Fun fact: It’s safer to drive a tanker full of ANFO than a tanker full of milk.
Why is that exactly? Is it because the conservation of momentum of a liquid makes the vehicle more difficult to control?
ANFO is basically impossible to detonate without the right primer and milk tanks can’t have baffles in them so the sloshing liquid is not fun on acceleration, braking or turning.
Reminder that basically impossible ≠ impossible. The Beirut explosion was a big bunch of ANFO going off.
Most sites bring it unmixed and mix the ammonia nitrate and diesel on site.
Why can't milk tanks have baffles?
EDIT: I looked it up it's because the baffles add complexity to cleaning for food grade reasons. So it's not because they can't, but rather because logistics companies won't due to increased cost.
I asked my milkman this once, he told me to shutup and mind my own business.
I thought to myself, how dairy.
Because you'd end up with a load of butter from the churning.
This guy tanks.