This is an actual pour, and I suspect the cost associated with these expansive cements would be prohibitive. On top of that, their workability time is way too short for a slab of this size: You couldn't mix 40 50# sacks before the first 10 would be beyond workability, resulting in more potential cold joints.
The water issue can be addressed using elastomeric sealants, and a quality concrete flatwork contractor will have excellent suggestions for Greg's particular situation. (for all we know, he lives in Texas!)
I am going to bookmark those materials, though, Jay. They look really useful for patching wall penetrations and stuff!