[quote=“octavian, post:22, topic:240”]
You might need 1’ thick walls and thrice the rebar with the shown design to achieve the same strength as a few inches of concrete using a curve-based design.
A flat plane is like a beam. Put a load in the center of a horizontal beam and it breaks at say X lbs.
Now let’s imagine an arch. An arch is a much stronger shape, it converts the load into compression.
A tube is basically a self-supporting arch all the way around in two dimensions, then extruded.
A sphere is an arch in three dimensions, and thus stronger than the 2d arch.
If a sphere section requires X amount of reinforcement, a tube requires 2X for the same strength yield. A flat wall might require 4x or more for the same strength.
And while you say this is to simplify construction, it actually could prove to be much more expensive and much less simple than what I’m about to propose to you.
Well, don’t you have to use rebar for the torus?
Sure you do, but a whole lot less. You can likely get away with 8" squares for the torus–that’s what the Monolithic people use. A tube needs twice that amount. A flat wall, probably twice again.
Although, there is one mitigating factor that I haven’t talked much about. Basalt rebar is considerably stronger than steel rebar, measured in gigapascals of tensile strength. But again, it’s for an architect to do the math on.
If so,curving the rebar to the torus design wouldn’t be more expensive (in man hours) than a straight rebar set up and also more complicated?
Basalt rebar is far more flexible than steel rebar. Where steel rebar has to be actively bent, basalt rebar can do easy curves in about 5’ radiuses. In fact it ships in coils and readily straightens out, spring-like. So as long as you have a design which doesn’t require a tight curve, you’re fine.