Patent GB-808312-A (GB)
Title: Improvements in or relating to the construction of floors and the like
Inventor: DOBLE CECIL EDWIN
IPC: E04C3/22
Filed: 1955-06-17
Abstract: 808,312. Floors; walls; beams. TRUSSED CONCRETE STEEL CO. Ltd. Sept. 17, 1956 [June 17, 1955], No. 17617/55. Class 20(4) A unit 1 for the construction of floors, walls, roofs, beams and columns comprises a series of hollow blocks 4, 5 assembled end-to-end with a unitary reinforced concrete filling 19 cast in a recess in one side of the blocks and extending throughout their length. The hollow interiors form a continuous duct from one end of a row of blocks to the other. As shown, the filling is T-shaped, alternatively, it may be U-shaped. When used for floors a concrete layer 2, Fig. 2, is cast over the units to form a slab with depending ribs 3 which fill channels between adjacent .nits. The blocks 4, 5 are of concrete or clay and, as shown, have projecting flanges 8, 9, 11, 12. The units are made with the blocks in an inverted position, reinforcing wires 18 which may be prestressed are placed as shown and concrete 19 is poured and screeded level with the flanges 8, 12. The end of the unit may be formed by inserting the larger ends of tapered hollow blocks into the hollow ends of the units and casting concrete about the projecting ends or by blocking off the interiors 7, Fig. 13, of the end blocks 4, 5 by means of blocks having apertures 38 and casting the concrete 19 within a mould formed by shuttering. Removable core pieces including stop ends may be used to provide extensions of the ducts formed by the hollow interiors of the unit. The apertures in the unit ends or extensions provide grips for handling or lifting and access for steam flow if rapid curing is required. Fig. 18 shows stop ends consisting of rubber-faced metal plates 33, 34 forced against the end blocks of a unit by driving home a centre wedge 52 situated between wedges 51, 53. Plates 54 laid over the wedges provide a level surface for screeding. Methods of keying the blocks to the cast filling and the unit to the cast-in-situ covering concrete comprise providing longitudinal corrugations in the blocks, Fig. 24 (not shown), tapering the blocks so that the smaller end of one abuts the larger end of another forming a longitudinal key, providing ribs on the upper surfaces of the blocks, eliminating part of the abutting lateral flanges of the blocks so that the concrete 19 keys to the blocks and at the same time provides an inspection point on each block to reveal the centre cast reinforced rib, or making alternate blocks in each row of different cross-sectional dimensions thus forming rebated keys. The finished floor may incorporate spacing members in the form of hollow blocks 76, Fig. 36, between the units through which vertical pipes may pass or the spacing members may carry service pipes and can be connected to each other by lateral holes in the units 1 which are provided by "makeup" blocks which are of heavier construction than the normal units. The units may be incorporated between reinforced or prestressed concrete beams for which they may be used for shuttering purposes. In a modification, the units 1 may have a single row of blocks instead of the combined blocks 4, 5, the single block having a thin vertical central portion, Fig. 42 (not shown) which provides two hollow ends as before.