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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 />2.13 CONCRETE MIXING <br />A. Ready -Mixed Concrete: Measure, batch, mix, and deliver concrete according to ASTM C 94, and <br />furnish batch ticket information. <br />When air temperature is between 85 and 90 deg F, reduce mixing and delivery time from 1 -1/2 <br />hours to 75 minutes; when air temperature is above 90 deg F, reduce mixing and delivery time <br />to 60 minutes. <br />PART 3 - EXECUTION <br />3.1 CONCRETE FORM PREPARATION <br />A. General: Comply with requirements of ACI 301 for formwork, and as herein specified. The <br />contractor is responsible for design, engineering, and construction of formwork, and for its timely <br />removal. <br />B. Earth Forms: Hand trim bottoms and sides of earth forms to profiles indicated on the drawings. <br />Remove loose dirt before placing concrete. <br />C. Construct formwork so concrete members and structures are of size, shape, alignment, elevation, <br />and position indicated, within tolerance limits of ACI 117. <br />D. Limit concrete surface irregularities, designated by ACI 347R as abrupt or gradual, as follows: <br />1. Class A, 1/8 inch, at all floors. <br />2. Class B, 1/4 inch, at all other work. <br />E. Construct forms tight enough to prevent loss of concrete mortar. <br />F. Fabricate forms for easy removal without hammering or prying against concrete surfaces. Provide <br />crush or wrecking plates where stripping may damage cast concrete surfaces. Provide top forms for <br />inclined surfaces steeper than 1.5 horizontal to 1 vertical. Kerf wood inserts for forming keyways, <br />reglets, recesses, and the like, for easy removal. <br />1. Do not use rust- stained steel form- facing material. <br />G. Set edge forms, bulkheads, and intermediate screed strips for slabs to achieve required elevations <br />and slopes in finished concrete surfaces. Provide and secure units to support screed strips; use strike - <br />off templates or compacting -type screeds. <br />H. Provide temporary openings for cleanouts and inspection ports where interior area of formwork is <br />inaccessible. Close openings with panels tightly fitted to forms and securely braced to prevent loss <br />of concrete mortar. Locate temporary openings in forms at inconspicuous locations. <br />L Chamfer exterior corners and edges of permanently exposed concrete. <br />J. Form openings, chases, offsets, sinkages, keyways, reglets, blocking, screeds, and bulkheads <br />required in the Work. Determine sizes and locations from trades providing such items. <br />K. Clean forms and adjacent surfaces to receive concrete. Remove chips, wood, sawdust, dirt, and other <br />debris just before placing concrete. <br />CAST -IN-PLACE CONCRETE 033000-8 <br />