@emilyh5FZPY
You cannot create an expansion join in a floor element using the split or split with gap tool. The split tool is intended for linear elements such as walls and beams...Nonetheless, in some instances the gap will not apply due material behaviour.
- To create expansion joins in floor elements simply create the gap in the floor's sketch. Floors allow for multiple loops hence you can model multiple joints within one floor elements. However, if you intend to have custom cut to size tile at the joints it might be a good idea to model the

for Rebars/Reinforcement you could use the Split with Gap tool; however, modelling your elements as separate components, they would be reinforced as separate components and splitting the rebars in such case will not be required considering that they have not been modelled as continuous bars the first place.