Patent GB-709706-A (GB)
Title: An improved structional unit and structures built up from such units
Inventor: HAMILTON ARCHIBALD MILNE
IPC: E01D15/133
Filed: 1950-07-20
Abstract: 709,706. Metalwork structural elements; floors; girders; bridges. BRITISH INSULATED CALLENDER'S CONSTRUCTION CO., Ltd., SOC. D'EXPLOITATION DES ETABLISSMENTS PAINDAVOINE FRERES, and HAMILTON, A. M. July 19, 1951 [July 20, 1950; July 20, 1950; July 20, 1950; Dec. 4, 1950], Nos. 18178/50, 18179/50, 18180/50 and 29635/50. Classes 20 (1), 20 (2) and 20 (4) A constructional unit of for instance steel, aluminium or concrete, particularly for building bridges, has the form of a hollow rectangular prism, Fig. 2, several times longer than its breadth and two rows of bolt holes a-d one along each side wall and registering with one another and openings 5 in the top giving access to the interior. Each unit has a base, side walls 2, end walls 6 and a top wall formed of inwardly bent flanges 3 formed by plates 4, or channel side members may be welded or riveted to a baseplate. The unit may be strengthened by a longitudinal central I-beam or transverse or longitudinal partitions. Fig. 5 shows a concrete unit. Various constructions of decking for bridges are shown and the bolt holes for connecting bolts are arranged to allow the units to be staggered longitudinally as shown in Fig. 10 in which the units D are mounted on pairs of cross span members 10 joining the trusses of a bridge and are staggered by a distance approximating to that between these cross span members. The gaps left by the staggered units at the ends of the bridge are filled by short units E the same length as the stagger. A dowel for connecting the bolt holes is shown in Fig. 9 and is a drive fit in the bolt-holes on one side of the central collar and is of smaller diameter on the other side. The units are clamped to the members 10. The ends of the units may be connected by a member 14. A footway formed of the units is mounted at a higher level on either side of the deck on transverse channel members. The units may be assembled open side up and filled with concrete or other road material. The units may be bolted together by the bars passing from side to side through all the courses. A second deck of units transversely disposed with respect to the first deck may be arranged above or below it. Bridges having the units arranged transversely to the bridge span are described with reference to Figs. 11, 12 (not shown). Bolt holes are provided in the base and top wall to allow bolting the units together in various attitudes for the decking of bridges. Long and short units of Fig. 2 and Fig. 3 (not shown) respectively are used to construct bridge decks, Figs. 13-15 (not shown) an abutment, Fig. 16, or a pier, Fig. 17. The abutment, Fig. 16, carries one end of a bridge Bland comprises a base frame of units B7, C7, C13 to which is bolted upright units B8, C9 tied together by horizontal units B10-12 and B14. The pier, Fig. 17, comprises a base of units B15 tied together by three units B16, B17 forming a channel beam on which are mounted two walls of vertical units B18, B19 spaced apart by horizontal units B20, B21. Channel beams suchas B16, B17, Fig. 17, are shown used as bridge deck supports in Figs. 18-20 (not shown). Fig. 23 shows a tied arch truss bridge, each truss comprising an arched member built of lengths of channel beam G2 similar to B16, B17, Fig. 17, connected by gussets 27 and tie members 28 to a horizontal chord formed of three courses of units, two courses base to base and the third and lower course B24 having its base uppermost. The trusses are connected by horizontal units B25, B26 which support the deck. In Fig. 24 two units are connected end to end by fish plates 29 passing between the side walls 2 and the upturned ends 30 of the end walls 6. The second Provisional Specification describes a unit comprising channel members welded to a base plate with the flanges of the channels turned outwards. The third Provisional Specification describes a unit comprising a channel having the edges of the flanges bent inwards then outwards again to form flanged rims.