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DocuSign Envelope ID:070B6BC7-CDE2-4AO8-BE62-07FA6BFDO53B <br /> 11/20/2020 <br /> 2.6 CURING MATERIALS <br /> A. Absorptive Cover: AASHTO M 182, Class 3, burlap cloth made from jute or kenaf, weighing <br /> approximately 9 oz./sq. yd.dry. <br /> B. Moisture-Retaining Cover: ASTM C 171,polyethylene film or white burlap-polyethylene sheet. <br /> C. Water: Potable. <br /> D. Evaporation Retarder: Waterborne, monomolecular, film forming, manufactured for application <br /> to fresh concrete. <br /> E. Clear, Waterborne, Membrane-Forming Curing Compound: ASTM C 309, Type 1, Class B, <br /> dissipating. <br /> F. White, Waterborne, Membrane-Forming Curing Compound: ASTM C 309, Type 2, Class B, <br /> dissipating. <br /> 2.7 RELATED MATERIALS <br /> A. Joint Fillers: ASTM D 1751, asphalt-saturated cellulosic fiber in preformed strips. <br /> 2.8 CONCRETE MIXTURES <br /> A. Prepare design mixtures, proportioned according to ACI 301, for each type and strength of <br /> normal-weight concrete,and as determined by either laboratory trial mixtures or field experience <br /> and or NCDOT approved Mix design. <br /> 1. When automatic machine placement is used, determine design mixtures and obtain <br /> laboratory test results that comply with or exceed requirements. <br /> B. Cementitious Materials: Limit percentage, by weight, of cementitious materials other than <br /> portland cement in concrete as follows: <br /> 1. Fly Ash or Pozzolan: 25 percent. <br /> 2. Combined Fly Ash or Pozzolan,and Slag Cement: 50 percent, with fly ash or pozzolan not <br /> exceeding 25 percent. <br /> C. Add air-entraining admixture at manufacturer's prescribed rate to result in normal-weight concrete <br /> at point of placement having an air content as follows: <br /> 1. Air Content: 4-1/2 percent plus or minus 1-1/2 percent for 1-inchnominal maximum <br /> aggregate size. <br /> D. Limit water-soluble, chloride-ion content in hardened concrete to 0.15 percent by weight of <br /> cement. <br /> E. Chemical Admixtures: Use admixtures according to manufacturer's written instructions. <br /> 1. Use water-reducing admixture in concrete as required for placement and workability. <br /> 32 13 13 CONCRETE PAVING Page 5 of 11 <br />