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9/2/2020 <br /> <br />32 13 13 CONCRETE PAVING Page 5 of 12 <br />a. Specific Gravity:0.91 <br />b. Melting Point:320 degrees F ( 160 degress C) <br />c. Ignition Point:1,094 degrees F (590 degrees C) <br />d. Water Absorption: None <br />e. Modulus of Elasticity:500 ksi <br />f. Tensile Strength:50ksi <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 />DocuSign Envelope ID: 7D9ACD4F-8F6C-42B6-9ADB-C60032DB6D03