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DocuSign Envelope ID:D561B1AE-DF34-4907-AD06-AOEB37BBE427 <br /> CHAPEL HILL ORANGE COUNTY VISITORS BUREAU August 12,2020 <br /> 308 WEST FRANKLIN,CHAPEL HILL,NC <br /> 2. Maximum Water-Cementitious Materials Ratio: 0.50. <br /> 3. Cementitious Materials: Use fly ash,pozzolan, ground granulated blast-furnace slag, and <br /> silica fume as needed to reduce the total amount of portland cement, which would <br /> otherwise be used,by not less than 40 percent. <br /> 4. Slump Limit: 4 inches (100 mm), 8 inches (200 mm) for concrete with verified slump of <br /> 2 to 4 inches (50 to 100 mm) before adding high-range water-reducing admixture or <br /> plasticizing admixture,plus or minus 1 inch(25 mm). <br /> 5. Air Content: Maintain within range permitted by ACI 301 (ACI 301M). Do not allow <br /> air content of trowel-finished floor slabs to exceed 3 percent. <br /> C. Structural Lightweight Concrete Mix: ASTM C 330, proportioned to produce concrete with a <br /> minimum compressive strength of 3000 psi (20.7 MPa) at 28 days and a calculated equilibrium <br /> unit weight of 110 lb/cu. ft. (1762 kg/cu. m) plus or minus 3 lb/cu. ft. (48.1 kg/cu. m), as <br /> determined by ASTM C 567. Concrete slump at point of placement shall be the minimum <br /> necessary for efficient mixing,placing, and finishing. <br /> 1. Limit slump to 5 inches (125 mm) for troweled slabs and 4 inches (100 mm) for other <br /> slabs. <br /> 2.8 CONCRETE MIXING <br /> A. Ready-Mixed Concrete: Measure, batch, mix, and deliver concrete according to <br /> ASTM C 94/C 94M[and ASTM C 1116/C 1116], and furnish batch ticket information. <br /> 1. When air temperature is above 90 deg F (32 deg C), reduce mixing and delivery time to <br /> 60 minutes. <br /> B. Project-Site Mixing: Measure, batch, and mix concrete materials and concrete according to <br /> ASTM C 94/C 94M. Mix concrete materials in appropriate drum-type batch machine mixer. <br /> 1. For mixer capacity of 1 cu. yd. (0.76 cu. m) or smaller, continue mixing at least 1-1/2 <br /> minutes, but not more than 5 minutes after ingredients are in mixer, before any part of <br /> batch is released. <br /> 2. For mixer capacity larger than 1 cu. yd. (0.76 cu. m), increase mixing time by 15 seconds <br /> for each additional 1 cu. yd. (0.76 cu. m). <br /> 3. Provide batch ticket for each batch discharged and used in the Work, indicating Project <br /> identification name and number, date, mix type, mix time, quantity, and amount of water <br /> added. Record approximate location of final deposit in structure. <br /> PART 3 -EXECUTION <br /> 3.1 FORMWORK <br /> A. Design, construct, erect,brace, and maintain formwork according to ACI 301 (ACI 301M). <br /> MISCELLANEOUS CAST-IN-PLACE CONCRETE 033053 -4 <br />