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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. Maximum Slump for Concrete Containing High -Range Water- Reducing Admixture: 8 inches <br />after admixture is added to concrete with 2- to 4 -inch slump. <br />6. Air Content: Less than 3 percent (no air entrainment). <br />E. Exterior Concrete Pads: Proportion normal- weight concrete mix as follows: <br />1. Compressive Strength (28 Days): 4,000 psi. <br />2. Nominal Maximum Aggregate Size: 3/4 inch. <br />3. Combined Fly Ash and Pozzolan: Not more than 25 percent. <br />4. Maximum Slump: 4 inches. <br />5. Maximum Slump for Concrete Containing High -Range Water- Reducing Admixture: 8 inches <br />after admixture is added to concrete with 2- to 4 -inch slump. <br />6. Air Content: 6 percent, plus or minus 1.5 percent at point of delivery for 3/4 -inch nominal <br />maximum aggregate size. <br />F. Slab -on -Grade and Trench Walls: Proportion normal- weight concrete mix as follows: <br />1. Compressive Strength (28 Days): 4,000 psi. <br />2. Nominal Maximum Aggregate Size: 3/4 inch. <br />3. Minimum Cementitious Materials Content: 470 lb /cu. yd. <br />4. Combined Fly Ash and Pozzolan: Not more than 25 percent. <br />5. Maximum Slump: 3 inches prior to addition of water - reducing admixture; 8 inches after <br />addition of water - reducing admixture. <br />6. Air Content: Do not allow air content of troweled finished floors to exceed 3 percent. <br />G. Housekeeping Pads: Proportion normal- weight concrete mix as follows: <br />1. Compressive Strength (28 Days): 3,000 psi. <br />2. Nominal Maximum Aggregate Size: 3/4 inch. <br />3. Combined Fly Ash and Pozzolan: Not more than 25 percent. <br />4. Maximum Slump: 3 inches prior to addition of water- reducing admixture; 8 inches after <br />addition of water- reducing admixture. <br />5. Air Content: Do not allow air content of troweled fmished floors to exceed 3 percent. <br />H. Limit water - soluble, chloride -ion content in hardened concrete to 0.15 percent by weight of cement. <br />Admixtures: Use admixtures according to manufacturer's written instructions. <br />1. Use water - reducing admixture or high -range water - reducing admixture (superplasticizer) in <br />concrete, as required, for placement and workability. <br />2. Use water- reducing and retarding admixture when required by high temperatures, low humidity, <br />or other adverse placement conditions. <br />2.12 FABRICATING REINFORCEMENT <br />A. Fabricate steel reinforcement according to CRSI's "Manual of Standard Practice." <br />CAST -IN-PLACE CONCRETE 033000-7 <br />