GB651462A - Reinforced concrete construction - Google Patents

Abstract

651,462. Pre-stressed reinforced concrete. GLOVER, C. W. May 16, 1947. No. 13294. [Class 20(iv)] [Also in Group I] The wire reinforcements 9 of pre-cast concrete beams pass through one end of the mould and are pre-stressed by applying tension to wires 15, Fig. 1, or rods 37, Fig.. 4, secured to reinforcement-gripping dogs 36 and passing through holes in an anchor plate 5 or 38, means associated with the wires or rods, e.g. adjustable grippers 14 or nuts 39, bearing against the plate 5 or 38 to maintain the tension while the beam is cast. As shown in Fig. 1, the wires 15 pass over vertically adjustable pulleys 16 to a winch 17 on a block 10 mounted on wheels rolling on transverse rails 12. In a modification (not shown), each wire 15 is connected to a stress gauge connected by wires and pulleys to a transversely movable winch. As shown in Fig. 4, the reinforcements are tensioned by movement of the anchor plate 38 which is mounted on a carriage 40. A right- and left-hand screw 42, turned by a wheel 48, engages a nut 43 on the carriage and a fixed nut 44. A pointer 49 indicates the stress applied. In addition to the reinforcements 9, reinforcing wires 52 pass through holes in the plate 38 and are clamped by toothed wedges 53, Fig. 5. The dogs 36 comprise two spring. pressed toothed jaws 56.