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DocuSign Envelope ID:070B6BC7-CDE2-4AO8-BE62-07FA6BFDO53B <br /> 11/20/2020 <br /> F. Deposit and spread concrete in a continuous operation between transverse joints. Do not push or <br /> drag concrete into place or use vibrators to move concrete into place. <br /> G. Consolidate concrete according to ACI 301by mechanical vibrating equipment supplemented by <br /> hand spading,rodding,or tamping. <br /> 1. Consolidate concrete along face of forms and adjacent to transverse joints with an internal <br /> vibrator.Keep vibrator away from joint assemblies,reinforcement,or side forms.Use only <br /> square-faced shovels for hand spreading and consolidation. Consolidate with care to <br /> prevent dislocating reinforcement joint devices. <br /> H. Screed paving surface with a straightedge and strike off. <br /> I. Commence initial floating using bull floats or darbies to impart an open-textured and uniform <br /> surface plane before excess moisture or bleedwater appears on the surface.Do not further disturb <br /> concrete surfaces before beginning finishing operations or spreading surface treatments. <br /> J. Curbs and Gutters: Use design mixture for automatic machine placement. Produce curbs and <br /> gutters to required cross section, lines, grades, finish, and jointing. <br /> K. Slip-Form Paving: Use design mixture for automatic machine placement. Produce paving to <br /> required thickness,lines, grades, finish, and jointing. <br /> 1. Compact subbase and prepare subgrade of sufficient width to prevent displacement of slip- <br /> form paving machine during operations. <br /> 3.7 FLOAT FINISHING <br /> A. General: Do not add water to concrete surfaces during finishing operations. <br /> B. Float Finish: Begin the second floating operation when bleedwater sheen has disappeared and <br /> concrete surface has stiffened sufficiently to permit operations. Float surface with power-driven <br /> floats or by hand floating if area is small or inaccessible to power units. Finish surfaces to true <br /> planes. Cut down high spots and fill low spots. Refloat surface immediately to uniform granular <br /> texture. <br /> 1. Medium-to-Fine-Textured Broom Finish: Draw a soft-bristle broom across float-finished <br /> concrete surface,perpendicular to line of traffic,to provide a uniform, fine-line texture. <br /> 3.8 CONCRETE PROTECTION AND CURING <br /> A. General: Protect freshly placed concrete from premature drying and excessive cold or hot <br /> temperatures. <br /> B. Comply with ACI 306.1 for cold-weather protection. <br /> C. Evaporation Retarder: Apply evaporation retarder to concrete surfaces if hot, dry, or windy <br /> conditions cause moisture loss approaching 0.2 lb/sq. ft. x hbefore and during finishing <br /> operations. Apply according to manufacturer's written instructions after placing, screeding, and <br /> bull floating or darbying concrete but before float finishing. <br /> 32 13 13 CONCRETE PAVING Page 9 of 11 <br />