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The mass shall then be turned with ~ovels two (2) times dry and two (2) times
<br />Set, not including shoveling into wheelbarrows. · The requisite amount of water shall be
<br />supplied in a spray during~he wet turns~.
<br />
<br />and no
<br />
<br /> (c) REMIXING CONCRETE.~ No concrete shall .be
<br />concrete shall be retempered Or remixed,
<br />
<br />used which has pa~ti~ly set
<br />
<br />Section 3. Finish Mortar Proporti~ns.
<br />
<br /> The mortar shall consist of one (1) part of Portland Cement to one and one-
<br />half (l~) parts, of concrete sand, as hereinbefore specified, except that the sand
<br />must all pass a one-fourth (~) i~ch screen. Unless otherwise specified, lamp black she
<br />be used fo~ coloring in the proportion of one-fourth po~d to each sack of cement used.
<br />
<br />Secti,~ 4. Nixing Finish Mortar.
<br />
<br /> The mortar shall be mixed in a concrete mixer in the manner specified for
<br />concrete or in a water-tight mixing box. ~en a mixing box is used, the box shall be
<br />first filled approximately one-half (~) full of sand, the volume of which has been
<br />previously determined with a one (1) cubic foot measuring box. The sand shall be rodde
<br />off with a guage which shall be used for guaging each subsequent batch. The requisite
<br />number of sacks of cement shall then be added. The inspector shall be given an
<br />opportunity to check the number of sacks of cement used in each batch. The material
<br />shall then be dry mixed Oy turning at least three (3) times with a mortar hoe. Suffi cie
<br />water shall be added and mixing continued until the batch is uniform in color and con-
<br />sistency. The mortar must be used immediately after mixing and no retempering will be
<br />permitted.
<br />
<br />Part IV..
<br />
<br />CURB, GUTTER AND SIDEWALK CONSTRUCTION.
<br />
<br />Section 1. Cement Curb Construction.
<br />
<br />Cement curb shall be placed upon a subgrade prepared as here inb~O re described
<br />
<br /> (a) DIMENSIONS. All cement curbs shall be five (8) inches wide at the top,
<br />seven and one-half ~?~) inches wide at the bottom, and sixteen (16) inches in depth,
<br />having a batter of two and one-half (~) inches on the front face, unless otherwise note
<br />on the plans or other standard drawings on file in the office of the City Engineer.
<br />
<br /> (b) FORMS. Forms shall be of a width equal to the full depth of the curb,
<br />and for straight curbs shall be two (~) inches thick if of wood. Warped forms and form
<br />not having a smooth straight upper edge shall not be used. Front and back fo~ns shall
<br />always.be used. Rigid outside forms shall be provided for curb returns having radii ~
<br />two (~) three (3) or eight (8) feet. Benders of thin plank forms, rigidly placed, may
<br />be used for curb returns having a radius not specified above and for curb on any other
<br />curves. The top of both the back and front form shall be beveled and carefully set
<br />to grade and line so that a strike templet or guage will have a constant and uniform
<br />bearing on the form when moved longitudinally along the form. The bevel shall be
<br />cut to produce the slope hereinafter specified for the top surface of the curb. The
<br />curb forms shall be rigidly held in place by the use of not less than~lve (8) pairs of
<br />iron stakes to each twenty (~0) foot section of curb, and other sections in proportion.
<br />~hen wooden stakes are used they shall be at least two (2) inches in Cross-sections,
<br />Or equivalent thereto in strength, and for each twenty (20) foot section of curb, there
<br />shall be not less than seven (~) pairs of stakes. Clamps, spreaders and braces shall
<br />be freely used where required. Ail curb forms shall be braced both back and front by
<br />means of placing a 2" x 4" wooden brace, or equal, with one end against a stake firmly
<br />driven into the ground and the other end firmly placed against the form. The brace
<br />stakes shall, be set firmly in the ground at a distance, from the outside edge of the
<br />form, which.will attain the greatest bracing effect. The braces shall be seeu.~
<br />toenailed to the f~m or kep~ in place by other approved method, and spaced at Intervals
<br />of not more than ten (10) feet and at lesser intervals if necessar~ in order that the
<br />forms will be rigid and in good aligament. Before resetting forms that have been
<br />previously used, all mortar, dirt, nails, etc., shall be removed. The total length of
<br />the curb forum provided shall be not less than one-third (1-~} of the length of the curb
<br />constructed in one (1) day, Curb forms shall not be removed from the concrete in less
<br />than one-half (}) hour after the concrete has been tam,ed into place.
<br />
<br /> (c) PLACING CONCRETE. The subgrade and forms shall be thoroughly sprinkled
<br />with water before placing any concrete. The concrete shall be placed in the forms in
<br />layers not more than six (~) inches in depth and each layer shall be t~ped until the
<br />concrete is thoroughly compacted.
<br />
<br /> (d) PLASTERING AND FINISHING. Aa soon as the co,rote has been thor~ghly
<br />tamped the top of the curb shall be pleastered with a one-half (~).inch coat of finish
<br />mortar, prepared as hereinbefore s~ecified. As soon as the forms are removed, the
<br />fact of the curb shall receive one-Yourth (~) inch coat of this mortar, to a depth of
<br />not less than two (2) inches below the gutter line, but in no case to a total depth of
<br />less than twelve (12) inches. The back of the curb shall be treated in like manner to
<br />a depth of approximately four (4) inches. The plastered surface of the curb shall be
<br />well floated and tw~)w~led into the body of the cur~ before the concrete has set. It
<br />shall be smoothly polished and marked with joints at right angles to the curb line,
<br />into blocks of uniform length not less than two and one-fourth (2~).feet, nor more than
<br />three and one-half (3~) feet. The marks sh~l coincide with the construction Joints.
<br />The front edge of the top of the curb shall be rounded to a radius of approximately one
<br />(1) inch, and the back edge, to a ~ad~us of not more than one-half (~) inch. Unless
<br />otherwise specified the back edge of the top of alt curbs shall be one-fourth (~) inch
<br />higher than the front edge. The f~nished cUrb shall allow a true straight face, and
<br />top of uniform width fmee from humps, sags or inequalities. When a straight edge five
<br />(8) feet lonE is laid upon the top of the curb, it shall not vary more than one-fourth
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