Patent GB-469098-A (GB)
Title: Improvements relating to light weight floors, roofs, walls, doors and like building constructions
IPC: E04C2/34
Filed: 1935-10-17
Abstract: 469,098. Composite metal structures ; doors. KAVANAGH, C. J. Oct. 17, 1935, No. 28654. [Classes 20 (ii) and 20 (iii)] A beam unit for forming floors, roofs, walls, doors, and like constructions comprises a flange member in the form of a dovetail-corrugated metal sheet connected to a metal stiffening member which extends longitudinally of the corrugations, interlocks with a dovetail corrugation of the sheet, and has a portion which projects from the sheet so as to form the web of the unit. The unit may be formed of two spaced sheets, at least one of which is provided with dovetail corrugations, and the sheets are connected together by metal stiffening members as specified above. The spaced sheets A, B shown in Fig. 1, are connected together by sheet metal stiffeners C comprising a web and hollow triangular flanges engaging the dovetails of the sheets. Adjacent sheets in each series are connected by means of interengaging and welded flanges E, F on the edges of the sheets, and such joints are covered by sheet-metal plates G, which are shaped to engage the adjacent dovetails in the sheets, and are formed with grooves H to facilitate snapping the plates in position. Instead of the joint E, F, the corrugations of adjacent sheets may be wedged in interfitting relation. A bead may be formed in the base of each of the triangular flanges on the stiffeners C to facilitate inserting the stiffeners in position. The spaced sheets A, B, Fig. 2, are connected at their ends by sheet-metal stiffeners J which have dovetail flanges to engage the end dovetails of the sheets and webs K shaped to make a spigot and socket joint with adjacent stiffeners. The stiffener shown in Fig. 3, comprises two hollow triangular flanges, a stepped web L, and a strip M which enters the hollow flanges ; the stepped web L may be in the form of a wood block. The sheets A, B shown in Fig. 4, have wide corrugations M1 of undercut form for engagement by the flanges of an I- beam stiffener N ; cover plates or clips Q may engage over the wide corrugations M<1>. The stiffener Z shown in Fig. 6, comprises two web plates welded together and having open dovetail flanges to engage the dovetails of the sheets A, B. The stiffener R shown in Fig. 7, is of Z-shape, the flange portions being either open or closed. The sheets A, B, Fig. 13, are arranged with the corrugations at rightangles and are connected together by stiffeners j, each of which has a hollow flange to key with the upper sheet A and a hollow web adapted to be welded to the lower sheet B. The hollow web and flange may be welded together or formed integrally. A transverse stiffener k, Fig. 13, is provided with dovetail projections on its upper edge to engage in the corrugations of the sheet A, and one or more of these projections may have recesses l, m to provide a resilient engagement. Each of the sheets A, B may be associated with a set of stiffeners having hollow flanges to key with the sheet, and the two sets of stiffeners are connected together, preferably by welding, at approximately the neutral axis of the beam. The stepped stiffener S, Fig. 15, serves as a door frame and has corrugations to engage the end corrugations of the sheets A, B ; wood supports U are laid in the corrugations of the sheet A for the purpose of securing a covering of plaster or other boards, and plaster W may be provided on the sheet B, one or more of the corrugations in this sheet being closed by caps X to provide conduits for electric cables &c. The corrugated sheets A, B may be of plain, perforated or expanded form, and where one of the two sheets to be connected is without dovetail corrugations, the stiffeners may be secured thereto by welding, bolting or riveting. If desired, one or each of the two spaced sheets may comprise two superposed and connected dovetail sheets. In order to avoid metal to metal contact at the junction of adjacent units, jointing strips of mastic compounds may be used. A sheet of aluminium foil or other insulating material may be introduced into the hollow space between the sheets. The beam units may be extended in length by assembling the adjacent sheets so that the corrugations overlap and provide continuous dovetail channels in which rods or strips of steel may be anchored. For connecting roof and wall members formed of hollow units as shown in Figs. 8 and 9, a gusset plate Z of mitred or L-shape is provided for engaging the interior of the adjacent hollow stiffeners Y of the units. A composite sill and window frame member may be provided with vertical pieces at the sides of the frame and below the sill for engaging the dovetails of adjacent hollow wall units. A door may be formed of dovetail-corrugated sheets separated by stiffeners and provided on all sides with end closure members shaped to fit into the corrugations. The Provisional Specification describes also channel-shaped end members or stiffeners which connect two spaced metal sheets and have plain or dovetailed flanges for engaging the ends of the spaced sheets internally or externally. The web portions of the channel members may have rectangular or circular projections and recesses, and they may be provided with longitudinal ribs or vertical corrugations.