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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 />3. Install joint - filler strips in lengths as long as practicable. Where more than one length is <br />required, lace or clip sections together. <br />E. Dowel Joints: Install dowel sleeves and dowels or dowel bar and support assemblies at joints where <br />indicated. <br />1. Use dowel sleeves or lubricate or asphalt -coat one -half of dowel length to prevent concrete <br />bonding to one side of joint. <br />F. Waterstops: <br />1. Self- Expanding Strip Waterstops: Install in construction joints and at other locations indicated, <br />according to manufacturer's written instructions, bonding or mechanically fastening and firmly <br />pressing into place. Install in longest lengths practicable. <br />3.7 CONCRETE PLACEMENT <br />A. Before placing concrete, verify that installation of formwork, reinforcement, and embedded items is <br />complete and that required inspections have been performed. <br />B. Before placing concrete, water maybe added at Project site, subject to limitations of ACI 301. <br />1. Do not add water to concrete after adding high -range water - reducing admixtures to mix. <br />C. Deposit concrete continuously or in layers of such thickness that no new concrete will be placed on <br />concrete that has hardened enough to cause seams or planes of weakness. If a section cannot be <br />placed continuously, provide construction joints as specified. Deposit concrete to avoid segregation. <br />D. Deposit concrete in forms in horizontal layers no deeper than 24 inches and in a manner to avoid <br />inclined construction joints. Place each layer while preceding layer is still plastic, to avoid cold <br />joints. <br />1. Consolidate placed concrete with mechanical vibrating equipment. Use equipment and <br />procedures for consolidating concrete recommended by ACI 309R. <br />2. Do not use vibrators to transport concrete inside forms. Insert and withdraw vibrators vertically <br />at uniformly spaced locations no farther than the visible effectiveness of the vibrator. Place <br />vibrators to rapidly penetrate placed layer and at least 6 inches into preceding layer. Do not <br />insert vibrators into lower layers of concrete that have begun to lose plasticity. At each insertion, <br />limit duration of vibration to time necessary to consolidate concrete and complete embedment of <br />reinforcement and other embedded items without causing mix constituents to segregate. <br />E. Deposit and consolidate concrete for floors and slabs in a continuous operation, within limits of <br />construction joints, until placement of a panel or section is complete. <br />1. Consolidate concrete during placement operations so concrete is thoroughly worked around <br />reinforcement and other embedded items and into corners. <br />2. Maintain reinforcement in position on chairs during concrete placement. <br />3. Screed slab surfaces with a straightedge and strike off to correct elevations. <br />4. Slope surfaces uniformly to drains where required. <br />CAST -IN-PLACE CONCRETE 033000-11 <br />