I’m not an engineer by any stretch, but I imagine it would be the downward force of the weight of the rest of the building on the top-middle of the butt. The resulting pressure would hold the rest in place.
For all the other arch types I’d agree. That draped arch looks like the stones at the middle of each nadir should spit themselves out rather than be held in.
I’m an engineer (not civil though), and yeah it’s the same principle as any other arch. If you look at the block cuts in order for any one to go down it has to push another away from the middle, but at the end of the chain of that it hits the wall.
What the hell holds up a draped arch?
I’m not an engineer by any stretch, but I imagine it would be the downward force of the weight of the rest of the building on the top-middle of the butt. The resulting pressure would hold the rest in place.
For all the other arch types I’d agree. That draped arch looks like the stones at the middle of each nadir should spit themselves out rather than be held in.
I’m an engineer (not civil though), and yeah it’s the same principle as any other arch. If you look at the block cuts in order for any one to go down it has to push another away from the middle, but at the end of the chain of that it hits the wall.