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I, <br />u <br />E <br />E <br />7 <br />11 <br />fl <br />l7 <br />[1�1 <br />n <br />n <br />u <br />B. Formwork, mixtures and concrete placement workmanship shall be such that <br />concrete surfaces, when exposed, will require only minimal finishing with no <br />excess honeycombing, voids or irregular color lines. <br />3.06 FORMS <br />06/07 <br />A. Forms shall be used for all concrete masonry, including footings. Forms shall be <br />so constructed and placed that the resulting concrete will be of the shape, lines, <br />dimensions, appearance, and to the elevations indicated on the Drawings. <br />B. Forms shall be made of wood, metal, or other approved material. Wood forms <br />shall be constructed of sound lumber or plywood of suitable dimensions, free from <br />knotholes and loose knots; where used for exposed surfaces, boards shall be <br />dressed and matched. Plywood shall be sanded smooth and fitted with tight joints <br />between panels. Metal forms shall be of an approved type for the class of work <br />involved and of the thickness and design required for rigid construction. <br />C. Edges of all form panels in contact with concrete shall be flush within 1/32 -inch and <br />forms for plane surfaces shall be such that the concrete will be plane within <br />1/16 -inch in 4 feet. Forms shall be tight to prevent the passage of mortar and <br />water and grout. <br />D. Forms for walls shall have removable panels at the bottom for cleaning, inspection, <br />and scrubbing -in of bonding paste. Forms for walls of considerable height shall be <br />arranged with tremies and hoppers for placing concrete in a manner that will <br />prevent segregation and accumulation of hardened concrete on the forms or <br />reinforcements above the fresh concrete. <br />E. Molding or bevels shall be placed to produce a 3/4 -inch chamfer on all exposed <br />projecting corners, unless otherwise shown on the Drawings. Similar chamfer <br />strips shall be provided at horizontal and vertical extremities of all wall placements <br />to produce "clean" separation between successive placements as called for on the <br />Plans. <br />F. Forms shall be sufficiently rigid to withstand vibration, to prevent displacement or <br />sagging between supports, and constructed so the concrete will not be damaged <br />by their removal. The Contractor shall be entirely responsible for their adequacy. <br />G. Forms, including new pre -oiled forms, shall be oiled before reinforcement is placed <br />with an approved non - staining oil or liquid form coating having a non - paraffin base. <br />H. Before form material is re -used, all surfaces in contact with concrete shall be <br />thoroughly cleaned, all damaged places repaired, all projecting nails withdrawn, all <br />protrusions smoothed and in the case. of wood forms pre - oiled. <br />Form ties encased in concrete shall be designed so that after removal of the <br />projecting part, no metal shall be within 1 -inch of the face of the concrete. That <br />part of the tie to be removed shall be at least 1/2 -inch diameter or be provided with <br />a wood or metal cone at lease 1/2 -inch in diameter and 1 -inch long. Form ties in <br />concrete exposed to view shall be the cone - washer type equal to the Richmond <br />"Tyscru ". Throughbolts or common wire shall not be used for form ties. <br />03300 -8 03 -4197 <br />