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Cast Cement Block: While various materials were formerly used for pipes—wood, wrought iron, cement-lined stovepipe, wrought steel, steel plate, reinforced concrete, galvanized steel, and cast iron—the present trend is to use cast-iron pipe (cement lined in regions where the water is aggressive) or asbestos-cement pipe. The sizes of pipe where hydrants are to be served should never be less than 8 inches, except in small, limited systems. Street mains larger than 48 inches are uneconomical, although 72-inch pipes are sometimes used, as in Jersey City and in Brooklyn. Large cast-iron pipes are subject to shrinkage and other stresses, which make them less reliable than steel or reinforced concrete in cases of heavy pressure or traffic loads.
Garden steps need not always conform to a straight format. Where you have enough space, consider creating a flight composed of circular or segmental treads to scale a graceful shallow rise in the ground, perhaps leading to a formal terrace beyond.
Mark out the shape of the steps with an improvised pair of compasses made from a length of wood attached to a stake with string. Cut out the rough shape of the circular treads and cast cement block foundations beneath. There is no need to make the foundation block round; just cover the corners with soil after you have built the steps.
Use bricks or blocks laid on mortar to form the curving front edges of the treads, and fill the circles with gravel or cobblestones. You could even lay turf for a grassy flight of steps, but it is important to bear in mind that these would be very difficult both to maintain and to mow satisfactorily.
On a large flight—more than, say, about 10 steps—it is advisable to cast a cement footing in a trench at the base to support the bottom riser and prevent the entire flight from sliding down the bank. Dig the trench under the position of the bottom riser, about twice the front-to-back measurement of the riser, about 4in deep. Ram rubble into the base of the trench and top up to ground level with fresh cement. Compact the cement, level it and allow to set overnight before building on the surface. |
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