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Show METHOD OF STOPPIl-iu Lc':,a. Concrete-Waterproofing Work Is De scribed by Correspondent of the Engineering Record. The method of stopping leaks ir. concrete, described by a correspond-ent correspond-ent of the Engineering Record, consists con-sists in plastering the wet, leaking surface of the concrete with waterproofed water-proofed mortar. The mortar is kept from being washed away by suitable bracing against a properly constructed gasket. Assuming that a leak is to be repaired re-paired in a basement wall, Fig. 1, one foot or more above the floor, the loose material should be scraped or dug away, leaving a Baucer-shaped cavity as large in diameter as necessary. neces-sary. If the holes through which the water is leaking are large enough they can be stopped with plugs covered cov-ered with patches of burlap driven in tightly. ' The form is then prepared. In case the diameter of the saucer-shaped hole is six inches, a board, A, Fig. 2, two inches thick and eight inches square( will be required. A one-fourth-inch twisted-burlap rope, B, is tacked on the board and the latter nailed to a brace C. Enough one-to-two mortar, waterproofed, water-proofed, is prepared, to which has been added, just before leaving the mixing box, bichromate of soda to the amount' of one or two per cent, of the cement. This is added to make the mortar quick setting. The mortar is placed on the board in a cone-shaped mass and then thrust quickly and firmly with a twisting motion into the cavity.' The brace is driven into place at the same time. The process is illustrated in Fig. "3. The twisting motion aids in forcing the mortar into the smallest crevices and drives away such parts of the mortar as may have been squeezed out between the concrete con-crete and the gasket. A very simple application of the method is shown in Fig. 4. A more difficult application, but not impracticable, imprac-ticable, is one where it is desired to fl rrTT" s v ) Concrete Work. plaster large areas. A little experi. ence and patience makes the matter easy. A good waterproofing mixture ia made as follows: Concentrated lye, one-third pound; powdered alum, three-fourths pound, which should be mixed in one gallon of water at least one hour before using. All of this mixture is used to one sack of cement, and is poured in at the same time a.". the water used to temper the mortar. |