Flowable concrete mixtures have an aqueous foam admixture mixed therein to give the concrete mixture desired strength, flowability, and density. The concrete mixtures include a hydration stabilizer to stabilize the aqueous foam. The hydration stabilizer inhibits the reaction between the hydraulic cement and the water in the aqueous foam. The aqueous foam can be further stabilized using a fluorochemical surfactant. Preferred fluorochemical surfactants comprise an oligomer having at least one hydrophilic nonionic monomer and at least one hydrophilic anionic monomer.