GB642362A - An improved method of, and means for, supporting and adjusting movable shuttering for use in the construction of walls or the like from concrete or similar material - Google Patents

Abstract

642,362. Casting walls in situ. KWIKFORM, Ltd. Oct. 2, 1945, No. 25549. [Class 20(ii)] A scaffolding structure, for casting a concrete wall by a method in which shuttering only a fraction of the height of the wall is progressively raised as the wall is cast, comprises in combination two spaced rows of vertical columns 18, 19; a horizontal platform supported therefrom and composed of battens 30; shuttering members 12 adapted to form one face of the wall and disposed wholly to one side of both the rows of columns and having their wall forming faces directed away from the columns; means for supporting the shuttering from the columns and elevating means carried from the columns and adapted simultaneously to raise both the adjacent shuttering members carried by the columns and the adjacent part of the platform. The platform rests on the upper horizontal members 26 of frame units 23 each of which comprises two vertical tubular members 24, 25 mounted on the columns 18, 19 and connected by horizontal members 26, 27. Clamps 28 incorporated in the frame units secure transverse ledger members 29 which maintain the spacing of the frame units as described in Specification 642,367, which also describes the formation of the columns 18, 19 as multiple screw threads of very large pitch and the mounting of the frame units thereon. The shuttering is supported from the frame units by hooks 32 secured to plates 33 which are clamped to the inner vertical members 24 of the frame units, the hooks 32 engaging with horizontal tie-rods 35 which extend along the row of shuttering plates 12 and pass through openings in vertical reinforcing strips 14. An inner row of shuttering plates 11 is similarly suspended, but the supporting assembly on one side only of the wall is shown, for the sake of clarity. To raise the frame units and shuttering hollow jack screws 36 are freely mounted on some of the vertical bars 18, 19, a convenient arrangement being to mount them on alternate bars in each row, as shown in Fig. 1. Each jack screw is supported on its bar by a collar 52, and has an external screw thread 37, Fig. 2, which engages with an internal thread in the boss 38 of the bracket 39 so that, when the jack screw is rotated, the bracket 39 moves vertically. The jack screw is rotated by a ratchet pinion 55, Fig. 3, rigid therewith, engaged by a ratchet lever 56 pivoted on a pair of arms 57 mounted rotatably upon a recessed part of the jack screw on each side of the pinion, clockwise rotation of the arms 57 raising the bracket 39 on the jack screw. A vertical staging supporting bar 41 is rigidly secured to each end of the bracket 49 by a pair of nuts 42, one having a squared end 42A fitting into a square hole in the bracket. The nuts 42 and the collar 52 are shaped internally to correspond with the twisted form of the bars 41 and 18 (or 19) respectively. The lower ends of the supporting bars 41 associated with the outer vertical bars 19 are connected in a similar way to another bracket 44, Fig. 2A. The lower end of the outer tubular member 25 of the adjacent frame unit 23 rests in a socket 45 in the centre of the bracket 44, immediately beneath which is a clamping nut 46 similar to the nuts 42. The inner tubular member 24 of the frame unit 23 rests on a nut 46A similar to the nut 46 but provided with flanges recessed internally to receive the tube end. The lower ends of the inner supporting bars 41 are similarly connected to a bracket 47, one edge of which engages beneath a lower aligner bar 16 which is clamped to reinforcing strips on the shuttering plates by clamps 17. Additional support for the shuttering from the bars 41 is provided by the pins 51, Fig. 5, which pass through the ears 49 in the bracket 47, one each side of the member 24, and through the vertical reinforcing strips 14 of the shuttering plates. Concrete is first poured between the shuttering plates 11 and 12 when they are resting on the ground, with the brackets 39 at the lower end of their respective jack screws and the nuts 46 and 46A abutting beneath the brackets 44 and the vertical members 24 respectively. As soon as the concrete has partly set the ratchet levers 56 are actuated in turn so as gradually to raise the staging and shuttering until the brackets 39 have travelled along the lengths of the jack screws through a distance somewhat less than the height of the previously cast concrete, which distance may be the length of the jack screw, and the second course of concrete is poured. The nuts 46 and 46A are raised until they are again beneath the brackets 44 and the members 24 respectively, and the jack screws are positioned for raising the assembly through a further stage by turning them anti-clockwise by means of a tommy-bar inserted in one of the sockets 59, whereby the bracket 39 is brought again to the lower end of the jack screw. The collars 52 are then raised to support the jack, screw again, and the staging and shuttering are ready for a further elevation. To cast the walling of the average two storey dwelling house may entail five repetitions of the cycle of operations described. Specifications 570,661, 570,678, 594,666, 604,588 and 642,367 are referred to. Specification 581,429 also is referred to in the Provisional Specification.