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DocuSign Envelope ID: 313DA256 -1EDE- 4396- A716- 4C53B809027E <br />JERRY M. PASSMORE CENTER ADDITION AND RENOVATION <br />HILLSBOROUGH, NORTH CAROLINA <br />A. Joint Fillers: ASTM D 1751, asphalt - saturated cellulosic fiber in preformed strips. <br />B. Slip- Resistive Aggregate Finish: Factory - graded, packaged, rustproof, nonglazing, abrasive <br />aggregate of fused aluminum -oxide granules or crushed emery aggregate containing not less <br />than 50 percent aluminum oxide and not less than 20 percent ferric oxide; unaffected by <br />freezing, moisture, and cleaning materials. <br />C. Bonding Agent: ASTM C 1059, Type II, non - redispersible, acrylic emulsion or styrene <br />butadiene. <br />D. Epoxy Bonding Adhesive: ASTM C 881/C 881M, two- component epoxy resin capable of <br />humid curing and bonding to damp surfaces; of class suitable for application temperature, of <br />grade complying with requirements, and of the following types: <br />1. Types I and II, non -load bearing, for bonding hardened or freshly mixed concrete to <br />hardened concrete. <br />2.6 CONCRETE MIXTURES <br />A. Prepare design mixtures, proportioned according to ACI 301 (ACI 301M), for each type and <br />strength of normal- weight concrete, and as determined by either laboratory trial mixtures or <br />field experience. <br />1. Use a qualified independent testing agency for preparing and reporting proposed concrete <br />design mixtures for the trial batch method. <br />2. When automatic machine placement is used, determine design mixtures and obtain <br />laboratory test results that meet or exceed requirements. <br />B. Proportion mixtures to provide normal- weight concrete with the following properties: <br />1. Compressive Strength (28 Days): 3000 psi (20.7 MPa). <br />2. Maximum Water - Cementitious Materials Ratio at Point of Placement: 0.50. <br />3. Slump Limit: 4 inches (100 mm), plus or minus 1 inch (25 mm). <br />C. Add air - entraining admixture at manufacturer's prescribed rate to result in normal- weight <br />concrete at point of placement having an air content as follows: <br />1. Air Content: 5 -1/2 percent plus or minus 1.5 percent for 1 -1/2 -inch (38 -mm) nominal <br />maximum aggregate size. <br />D. Chemical Admixtures: Use admixtures according to manufacturer's written instructions. <br />1. Use water- reducing and retarding admixture when required by high temperatures, low <br />humidity, or other adverse placement conditions. <br />E. Cementitious Materials: Limit percentage by weight of cementitious materials other than <br />portland cement according to ACI 301 (ACI 301M) requirements. <br />CONCRETE PAVING 321313-5 <br />