GB190921850A - Improvements in and relating to Linings for Pits, Shafts and the like. - Google Patents

Abstract

21,850. Walker, C. Sept. 24. [Cognate Application, 26,820/09.] Shafts.-Cement or concrete linings for pits, shafts, &c. are formed of interlocking blocks with recesses or projections for enabling the blocks to be keyed to the wall of the pit &c. The recesses b, Figs. 14 and 22, may be central or at the ends, and may be ribbed; and the projections h may be central, as shown in Fig. 13, or overlapping, as shown in Fig. 12. The interlocking part d may be V shaped, Fig. 14, or Fig. 21, and may extend wholly or partly across the blocks; the side joints may be similar or plain. An overlapping tongue may engage recesses in adjoining blocks to form lap joints. Recesses e are formed to receive joint-making material and parallel grooves 22, Fig. 21, connected therewith, may be provided and also grooves 25 to receive rubber or other packings. The interlocking joints may be corrugated or the like. Pipes k, n, r, may be embedded in the blocks, through which cement may be forced to the joints or between the pit wall and the lining. Screws 30, Fig. 22, may be passed through the pipes k and nuts 28 to centre a ring of blocks ; or pins 4, Fig. 13, may be passed through the pipes and secured to loops 3 for raising the blocks into position. Boards may be fixed over the joints to hold the cement until it has set. Felt may be placed between joints, and the edges may be recessed to receive wooden wedge strips and cement. The blocks may be metal-cased or reinforced, or may be dipped in oil or tar preparations to prevent leakage of water through them. For assembling, pegs s, Fig. 14, may be driven into the pit wall, and on these, a foot-plate t carrying screw-jacks v, fish-plates x, and a segmental ring y are mounted. To the ring y, planks 1 are fixed, and a ring of blocks a is built on them. The space is then filled with cement, on a course of rubble if necessary. Another ring is then built in, and if necessary, cement is packed behind. Behind succeeding rings, rubble is packed until further keying to the pit wall is required, when more cement is used. In the cement-filled portions, drain-pipes 8 are inserted to connect the rubble-filled space above with the one below or with a garland &c. The lining may also be built on an annular ledge left in the pit wall, a flat slab 35 being first laid, and then a ring of preferaby wide crib blocks 34.