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C. Hot -Weather Concreting - Conform to ACI 305. <br />1. Take precautions when ambient air temperature is ninety degrees Fahrenheit (901F.) <br />or above. <br />2. Temperature of concrete at the time of placement shall not exceed eighty degrees <br />Fahrenheit (80°F.). <br />3. Cool forms and reinforcing to a maximum of ninety degrees Fahrenheit (901F.) by <br />spraying with water before placing concrete. <br />4. Do not use cement that has reached a temperature of one hundred seventy degrees <br />Fahrenheit (170°F.) or more. <br />5. Prevent plastic shrinkage and cracking due to rapid evaporation of moisture. <br />6. Do not place concrete when evaporation rate (actual or anticipated) equals or exceeds <br />0.20 pounds per square foot per hour, as determined by Figure 2.1.5 of ACI 305. <br />7. Set -retarding and water -reducing admixtures may be used with Engineer's approval <br />when ambient air temperature is ninety degrees Fahrenheit (901F.) or above to offset <br />accelerating effects of high temperature. <br />8. Water cure will be required for all flat slabs. <br />9. Refer to ACI 305 for further requirements. <br />PART 2 — PRODUCTS <br />2.1 CONCRETE MATERIALS <br />A. Cement: Furnish from one source. <br />1. Portland Cement Type II, or Type I/II. <br />a. Meet ASTM C150. <br />b. Alkalies: Maximum 0.60 percent. <br />c. Tricalcium Aluminate Content: Type II and Type 1/II Cement - Maximum 8 <br />percent. <br />d. Nonhydraulic Above -grade Structures: Type II, type UII. <br />e. Hydraulic and Below -grade Structures and Sewers: Type II, Type UII. <br />f. Combine fly ash with cement at batch plant or during production of cement in <br />accordance with ASTM C595, Type IP cement. <br />B. Aggregates: Furnish from one source. <br />1. Fine aggregate - ASTM C33. <br />2. Coarse aggregate - ASTM C33 except that air-cooled blast furnace slag will not be <br />allowed. <br />a. Nominal maximum size of coarse aggregate shall not be larger than: <br />Cast -In -Place Concrete February 2017 03300-7 <br />