I'd probably caulk all cracks with a tough but elastic caulk. obviously water needs a place to go away from the foundation so you are on the right track there. an outdoor slab needs to be able to float away from the building without resting on hard material that would cause cracks. The movement is greater here where it freezes. Without freeze action the only force would be settlement.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.