So a few days ago Elon Musk went on a podcast where at one point he explains that tunnels are earthquake proof, and using a submarine under the ocean during a storm as a sort of analogy. Now I’ve been wondering about this, to what degree would a tunnel system really be earthquake resistant? What kind of soil or ground would be needed for the tunnel to be earthquake resistant, and how sure can we be it’s safe. Now just based on some assumptions, I’m guessing a regular tunnel through a mountain or something isn’t earthquake proof, and instead it’s tunnels that go under hard ground are (which would be the case with a 3D road). Where could these tunnels function as earthquake resistant, and is it even the case? I doubt elon was bullshitting, although I don’t really understand the whole situation here maybe someone can give me some insight.
Edit: Should have specified in the title I’m talking about “underground tunnels”.