GB765679A - Improvements in or relating to a building member of reinforced concrete, and a method and mould for its manufacture - Google Patents

Abstract

765,679. Moulding concrete building elements. JANHUNEN, M. A. Dec. 24, 1953, No. 35908/53. Class 87(2). [Also in Group X] A mould for a concrete structural member 1 is formed of members 27, 28, 29, Fig. 13, laid side by side, an upper mould part 30 being vibrated in the longitudinal direction. A wooden nailing strip 14 may be attached to the concrete by embedded nails 31. The bed of the mould may be of concrete instead of wood, the lower floor surface being of sheet metal beneath which heating-tubes are arranged. In Fig. 15, the mould is wholly of sheet metal and the member 1 is cast in inverted position. A heating- tube 35 extends the entire length of the mould. A vibrator 36 is movable along the length of the mould. The concrete is supplied from a hopper 37. Fig. 16 shows members 1 being cast in superposed rows, the mould spaces being defined by metal under parts 40 and distance pieces 46,43. A vibrator 42 is pressed into the concrete and against the mould bottoms 40. The distance pieces 46 may fit into longitudinal grooves in the pieces 43. In Fig. 21, U-shaped and Z- shaped metal parts 40, 33 are laid around reinforcing wires 51, the cast members 1 being alternately upright and inverted. Partition plates 52 separate rows of moulds. The elements may be made partly of precast sections. For example, with precast sides 48 it is possible to pre-tension the reinforcement in the edges and ridge of the element by using the sides as stretching members. Alternatively, the edges 49 and ridge 50, Figs. 19, 20, may be precast and prestressed, the application of concrete for the sides requiring simple mould parts only. The precast edges 49, 50 may be used to pre-tension the transverse reinforcement of the sides.