Patent ID: 8246877

Claim:
A method for casting a concrete product with a substantially horizontal slipform casting process, the method comprising: feeding a concrete mix in one or more steps to a slipform casting apparatus comprising: a cast mold comprising side plates, a casting bed, and an adjustable compacting plate disposed above the casting bed; and a single hollow-core forming part having an upper surface and a lower surface defining a limited cross-section disposed within the cast mold above the casting bed and below the adjustable compacting plate, wherein the hollow-core forming part moves progressively along with the slipform casting apparatus and away from the cast concrete mix, and changing a distance between the upper surface of the hollow-core forming part and the lower surface of the hollow-core forming part during the slipform casting process, wherein changing the distance between the upper surface and the lower surface of the hollow-core forming part comprises turning tie rods, each having one end attached to the upper surface and another end attached to the lower surface of the hollow-core forming part, and wherein the concrete mix is fed around all sides of the hollow-core forming part so that the resulting concrete product has a hollow profile varying in cross-section along the length thereof.