What parts on Brunelleschi's dome we're the ones that supported the most weight?

The parts of Brunelleschi's dome that supported the most weight were the inner and outer shells of the dome, particularly the robust rib structure that runs vertically. These ribs helped distribute the weight effectively, while the double-shell design allowed for a lighter overall structure. The use of herringbone brickwork also contributed to the dome's stability and strength, enabling it to withstand the forces exerted by its own weight.