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Show CONCRETE FOR WEIRS Can Be Constructed at Moderate Moder-ate Cost and Will Last. Wooden Affairs Must Be Replaced In From Three to Six Yeara and Annual An-nual Maintenance la More or Lesa Expensive. (Hy It U I'AlttflfAM. Colo null) Agricultural Agricul-tural C'cilltUH.) Permanency In construction Is always al-ways ono of the basic principles of economy. We find that weirs constructed con-structed of wood last from three to tlx years, with an annual maintenance Df more or less expense. A weir that will last Indefinitely can be construct ud of concrete, at moderate first cost, and no mulntenanco charge. First, determine tho position of four weir and the maximum amount af water you expect to discharge through It. This having been done, sxcavate the ditch to a level surface, to a depth of four or fljo Inches below be-low the original bottom. The length it tbe base will be, In our case, say, eight feet. At each end of the foundation foun-dation pit make a small trench, reaching across the bottom from side to side. The width of the foundation will depend upon the size of the weir seeded. Assuming a two-foot weir, we would make tbe base five and one-balf one-balf feet. Now mix your concrete, jno part I'ortland cement, three parts and, and six parts gravel or broken tone, and place this In tho pit as provided. The smijll trenches at the snds will serve as a curtain wall and prevent tho water from flowing beneath be-neath the base. While the concrete is being placed there should be set a mantling two Inches square uinl full ength of base,, directly underneath iho center of tho side walls of the wlr. Now pluro four one half Inch 'rori rods In tho base, to extend vertl-:ally vertl-:ally on tho outside of tho scantling, and to extend some six or eight Inches ibove tho finished surface of the base. It Is advisable to bend the ends of :beso rods at right angles, the lower itnl extending out into the base at Ight angles to tho axis of the ditch. These rods should bo equally spaced, with first and last one a foot from Mich end of the wail. The two icantllngs will be parallel with each ather, and after tho concrete bus all Seen placed and tamped Into position, ind floated with a straight edge, these strips should be flush with the surface. sur-face. There should be a margin of :oncrete on the outside of them at least four Inches wide. The finished surface should be approximately level. No forms will be necessary for .. the construction of the base of the ' weir. The forms for the sides of the weir are of a collapsible nature and can be used for different widths and for in indefinite number of structures. Twelve piece of 2x8, nine feet long, constitute the four side pieces, two side pieces being required to form each side wall. At the ends of tbe outside out-side pieces are two long eye bolts reaching to the opposite side. These bolts are threaded for some distance, permitting of varying widths. To form the ends of the wall is placed veitl rally board, five Inches wide, two feet long, hold In place by cleats. Two pieces of 2x4 at each end, cut the proper length, serve as struts or spreaders. After the end boards forming tbe ends of the walls, and the struts are in place, the turn nuts on the eye bolts are tightened, thus causing caus-ing the whole form to be rigidly connected con-nected and properly spaced. The eye bolts are hinged at the diagonal corners cor-ners and the end pieces are slotted to permit of easy assembling. At about three feet from the lower end of wall must be placed the weir board. To provide a recess for it In the concrete side wall a 22x2 lnch cleat Is nailed vertically on the Inside of the Inside forms. A alight draft should be given to tbe clent so that there will bo less danger of crumbling the corners when the side pieces are taken off. To Insure In-sure an even surface for the weir board to rest against when in place, and to prevent excessive leakage, a small angle Iron, placed on the lower side of the cleat, and Imbedded In the concrete, will give excellent results when tbe weir board la wedged Into place. |