I am planning to pour concrete between two structures. the back and one side
is basement wall (cement blocks) on other side is concrete slab with
aluminum storage shed. the space is 11' x 3.5' and I am in Michigan.

Do I need expansion joints? if so is there a way to attach/glue them in
place? the alum shed has a flange thing on wall that goes over top 1" of
slab, and is not tight against slab in some places.......so sticks out a
bit....like 1/8" or so. what is best way to deal with this?

I have some paver/driveway base material that is crushed limestone I
believe....will 3" of this material work for foundation with no sand?

I am planning to pick up 60 lb bags of "Quickrete" concrete and mix in wheel
barrow. how and when to seal?