| 摘要 |
PCT No. PCT/FI85/00033 Sec. 371 Date Nov. 27, 1985 Sec. 102(e) Date Nov. 27, 1985 PCT Filed Apr. 1, 1985 PCT Pub. No. WO85/04361 PCT Pub. Date Oct. 10, 1985.A method of and a casting bed for producing a concrete product, especially an endless concrete blank prestressed in at least two directions. In order to enable a prestressing wire to be arranged in position and tightened in a simpler manner, at least one prestressing wire is passed in a zigzag-like manner crosswise between at least two fixed sides of a casting bed to form a wire net and the wire net is tightened from a third side of the casting bed in the direction of both first-mentioned sides so that the wire net is stretched in two directions by means of a traction in one direction. Finally, concrete is fed on the bed to form a prestressed concrete blank. An apparatus intended for carrying out the method comprises a weaving device for stretching the prestressing wires continuously and in a zigzag-like manner crosswise between two parallel sides of the casting bed and for tightening of the wires in the longitudinal direction of the casting bed. |
