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t H. Before form material is re -used, all surfaces in contact with concrete shall be thoroughly cleaned, all damaged places repaired, all projecting nails withdrawn, all protrusions smoothed and in the case of wood forms t pre - oiled. Form ties encased in concrete shall be designed so that after removal of the projecting part, no metal shall be within 1 -inch of the face of the concrete. That part of the tie to be removed shall be at least 1/2 -inch diameter or be provided with a wood or metal cone at lease 1/2 -inch in diameter and 1 -inch long. Form ties in concrete exposed to view shall be the cone - washer type equal to the Richmond "Tyscru ". Throughbolts or common wire shall not be used for form ties. 3.07 PLACING AND COMPACTING A. Unless otherwise permitted, the work begun on any day shall be completed in daylight of the same day. B. Concrete is not to be placed until reinforcing steel, pipes, conduits, sleeves, hangers, anchors and other work required to be built into concrete have been inspected and approved by the Engineer. Remove water and foreign matter from forms and excavation. All soil bottom for slabs and footings shall be approved by the Engineer before placing concrete. C. Transport concrete from mixer to place of final deposit as rapidly as practicable by methods which prevent separation of ingredients and displacement of reinforcement, and which avoid rehandling. Partially hardened concrete is not to be used. D. "Cold joints" are to be avoided, but if they occur, are to be treated as bonded construction joints. E. At construction joints the surfaces of the concrete already placed, including vertical and inclined surfaces, shall be thoroughly cleaned of foreign materials and laitance, and weak concrete and roughened with suitable tools to expose a fresh face. At least two hours before and again shortly before the new concrete is deposited, the joints shall be saturated with water. After glistening water disappears, the joints shall be given a thorough coating of neat cement slurry mixed to the consistency of very heavy paste. The surfaces shall receive a coating at least 1/8 -inch thick, well scrubbed -in by means of stiff bristle brushes whenever possible. New concrete shall be deposited before the neat cement dries. F. Deposit concrete to maintain, until the completion of the unit, a horizontal plastic surface. Vertical lifts shall not exceed 24- inches and preferably 18- inches. December 2006 03300 -11 06 -5723