Abstract: A method and apparatus for casting concrete elements with varying, determined length, equipped with one or with a plurality of longitudinal hollow cores, by means of a slipforming apparatus. The apparatus is movable with respect to the bed (2), said apparatus comprising forming members (10) for forming hollow cores. The mass is fed in the first step to the portion of the slab below the hollow cores, and in the second step the hollow-core forming members being brought onto the said portion of the slab and mass is being fed between the forming members and onto them. The forming member (10) for forming a hollow core comprises an attachable extension part (22). The height of a hollow core is changed by changing the extension part of the hollow core forming member.

Abstract: A method and apparatus are for fabricating a concrete product in a slip-form casting process, in which method concrete mix is fed into a slip-form mold of a defined cross section moving progressively in the casting process so as to obtain a concrete product of a desired shape. The method includes an interruptible guidance control of the prestressing tendons so as to allow the tendon guides to travel past supplementary parts such as reinforcing steels connected to the prestressing tendons.

Abstract: A method and apparatus are disclosed for fabricating a concrete product in a slip-form casting process, in which method concrete mix is fed into slip-form mold of a defined cross section moving progressevely in the casting process so as to obtain a concrete product of a desired shape. The method is characterized by an interruptible guidance control of the prestressing tendons so as to allow the tendon guides to travel past supplementary parts such as reinforcing steels connected to the prestressing tendons.