GB589808A - Roof and floor construction formed from shell structures - Google Patents

Abstract

589,808. Roofs and floors. POLLAK, E., and HOFFMANN, A. J. Aug. 3, 1944, No. 14816. [Class 20 (iv)] Roofs and floors are formed by "trussless shells" consisting of transversely-arched units of small thickness and of a length which is a multiple of the width, the shells acting as beams and being without gables frames or trusses but being provided with means which prevent undue transverse deformation under load at one or at a number of spaced transverse sections. The shells may be moulded or made by bending sheet material, and may be, for example, of concrete, metal, resinous plastics, plywood, or asbestos. Fig. 6 shows a roof formed of trussless shells 1 supported on beams 3, ties 2 preventing deformation in transverse planes. In a modification, the shells are suspended from the beams 3, and in another they are inverted. The ties 2 may be replaced by struts 2a, Fig. 7b, between the shells, or may pass through a number of shells to form both ties and struts, Fig. 7d (not shown), in which case they may form also carrying beams. Fig. 8 shows a cantilever construction in which the shells are threaded through curved slots 7 in a wall, their curvature varying from a maximum at this section to zero at their outer edges. Circular roofs are similarly formed, Figs. 9 and 10 (not shown). The shells form gutters, leading the water towards the support. When the shell are moulded the ties or other means preventing transverse deformation may be adjusted to provide a degree of transverse prestressing. In the case of bent-sheet shells the shape is maintained by the ties &c.