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<br />03300 - 7/22 <br />be consistently less than 40 degrees F, a non-corrosive set accelerating <br />admixture shall be used. Set accelerating admixture shall conform to ASTM C <br />494 Type C or E. <br />5. Normal range water reducer shall conform to ASTM C 494, Type A. The <br />quantity of admixture used and the method of mixing shall be in accordance <br />with the manufacturer's instructions and recommendations. <br />6. High range water reducer shall conform to ASTM C 494, Type F or G. High <br />range water reducer shall be added to the concrete after all other ingredients <br />have been mixed and initial slump has been verified. No more than 14 ounces <br />of water reducer per sack of cement shall be used. Water reducer shall be <br />considered as part of the mixing water when calculating the water/cement ratio. <br />a. If the high range water reducer is added to the concrete at the Site, it may <br />be used in conjunction with the same water reducer added at the batch <br />plant. Concrete shall have a slump of 3 inches plus or minus 1/2-inch <br />prior to adding the high range water reducing admixture at the Site. The <br />high range water reducing admixture shall be accurately measured and <br />pressure injected into the mixer as a single dose by an experienced <br />technician. A standby system shall be provided and tested prior to each <br />day's operation of the primary system. <br />b. Concrete shall be mixed at mixing speed for a minimum of 70 mixer <br />revolutions or 5 minutes after the addition of the high range water <br />reducer, unless recommended otherwise by the manufacturer. <br />2.06 CURING MATERIALS: <br />A. Curing compound shall conform to ASTM C 309, Type I. Curing compound shall be <br />white pigmented, resin based and compliant with local VOC requirements. When <br />curing compound must be removed for finishes or grouting, it shall be of a dissipating <br />type. Sodium silicate compounds shall not be allowed. <br />B. Polyethylene sheet for use as concrete curing blanket shall be white and shall have a <br />nominal thickness of 6 mils. The loss of moisture when determined in accordance <br />with the requirements of ASTM C 156, shall not exceed 0.055 grams per square <br />centimeter of surface. <br />C. Polyethylene-coated waterproof paper sheeting for use as concrete curing blanket <br />shall consist of white polyethylene sheeting free of visible defects, uniform in <br />appearance, have a minimum thickness of 2 mils, and be permanently bonded to <br />waterproof paper conforming to the requirements of Federal Specification UU-B- <br />790A. The loss of moisture, when determined in accordance with the requirements <br />of ASTM C 156, shall not exceed 0.055 gram per square centimeter of surface. <br />D. Polyethylene-coated burlap for use as concrete curing blanket shall be minimum 4- <br />mil thick, white opaque polyethylene film impregnated or extruded into one side of <br />the burlap. Burlap shall weigh not less than 9 ounces per square yard. The loss of <br />moisture, when determined in accordance with the requirements of ASTM C 156, <br />shall not exceed 0.055 grams per square centimeter of surface. <br />E. Curing mats for use in Curing Method 6 below, shall be heavy shag rugs or carpets <br />or cotton mats quilted at 4-inches on center. Curing mats shall weigh a minimum of <br />12 ounces per square yard when dry. <br />2.07 MISCELLANEOUS MATERIALS: