The giraffe is for us one of the biggest and heaviest known neighbors! If you see that someone weighs a ton it could be problematic but not for a giraffe, as they reach 1.4 tons easily or even more, the males. Females less although more than 700 kilograms.
Observing the skeleton, the sustaining bones aren't at all particularly oversized. The four legs don't always share the entire weight thus it looks like another example of the powerful molecular structure.
Males fight sometimes, some using their necks! A good moment to avoid a walk near these great creatures.