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9/2/2020 <br /> <br />32 13 13 CONCRETE PAVING Page 9 of 12 <br />C. Moisten subbase to provide a uniform dampened condition at time concrete is placed. Do not <br />place concrete around manholes or other structures until they are at required finish elevation and <br />alignment. <br />D. Comply with ACI 301requirements for measuring, mixing, transporting, and placing concrete. <br />E. Do not add water to concrete during delivery or at Project site. Do not add water to fresh concrete <br />after testing. <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 />DocuSign Envelope ID: 7D9ACD4F-8F6C-42B6-9ADB-C60032DB6D03