Stop in for a cup of coffee
Concrete Rule #1 .. Concrete cracks .. Best you can hope for is to control WHERE it cracks .. As far as strength goes .. The only way to get it to it's "design" strength is to keep it hydrated/under water for a month .. The slower the water leaves the placed concrete the better .. Don't keep adding water to the mud to make it easier to manhandle .. Bad JooJoo .. Dryer is better .. If covering it and keeping it wet is not an option .. Spray it with a sealant made for such ..