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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 />5. Begin initial floating using bull floats or darbies to form a uniform and open - textured surface <br />plane, free of humps or hollows, before excess moisture or bleedwater appears on the surface. <br />Do not further disturb slab surfaces before starting finishing operations. <br />F. Cold- Weather Placement: Comply with ACI 306.1 and as follows. Protect concrete work from <br />physical damage or reduced strength that could be caused by frost, freezing actions, or low <br />temperatures. <br />1. When air temperature has fallen to or is expected to fall below 40 deg F, uniformly heat water <br />and aggregates before mixing to obtain a concrete mixture temperature of not less than 50 deg F <br />and not more than 80 deg F at point of placement. <br />2. Do not use frozen materials or materials containing ice or snow. Do not place concrete on <br />frozen subgrade or on subgrade containing frozen materials. <br />3. Do not use calcium chloride, salt, or other materials containing antifreeze agents or chemical <br />accelerators, unless otherwise specified and approved in mix designs. <br />G. Hot - Weather Placement: Place concrete according to recommendations in ACI 305R and as follows, <br />when hot - weather conditions exist: <br />1. Cool ingredients before mixing to maintain concrete temperature below 90 deg F at time of <br />placement. Chilled mixing water or chopped ice may be used to control temperature, provided <br />water equivalent of ice is calculated to total amount of mixing water. Using liquid nitrogen to <br />cool concrete is Contractor's option. <br />2. Cover steel reinforcement with water - soaked burlap so steel temperature will not exceed <br />ambient air temperature immediately before embedding in concrete. <br />3. Fog -spray forms, steel reinforcement, and subgrade just before placing concrete. Keep subgrade <br />moisture uniform without standing water, soft spots, or dry areas. <br />3.8 FINISHING FORMED SURFACES <br />A. Smooth - Formed Finish: As -cast concrete texture imparted by form- facing material, arranged in an <br />orderly and symmetrical manner with a minimum of seams. Repair and patch tie holes and defective <br />areas. Remove fins and other projections exceeding 1/8 inch in height. <br />1. Apply to concrete surfaces exposed to public view or to be covered with a coating or covering <br />material applied directly to concrete, such as waterproofing, dampproofing, veneer plaster, or <br />painting. <br />2. Do not apply rubbed finish to smooth- formed finish. <br />B. Related Unformed Surfaces: At tops of walls, horizontal offsets, and similar unformed surfaces <br />adjacent to formed surfaces, strike off smooth and finish with a texture matching adjacent formed <br />surfaces. Continue final surface treatment of formed surfaces uniformly across adjacent unformed <br />surfaces, unless otherwise indicated. <br />3.9 FINISHING FLOORS AND SLABS <br />A. General: Comply with recommendations in ACI 302.1R for screeding, restraightening, and finishing <br />operations for concrete surfaces. Do not wet concrete surfaces. <br />CAST -IN-PLACE CONCRETE 033000-12 <br />