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9/2/2020 <br /> <br />32 13 13 CONCRETE PAVING Page 10 of 12 <br />3.8 CONCRETE PROTECTION AND CURING <br />A. General: Protect freshly placed concrete from premature drying and excessive cold or hot <br />temperatures. <br />B. Comply with ACI 306.1 for cold-weather protection. <br />C. Evaporation Retarder: Apply evaporation retarder to concrete surfaces if hot, dry, or windy <br />conditions cause moisture loss approaching 0.2 lb/sq. ft. x hbefore and during finishing <br />operations. Apply according to manufacturer's written instructions after placing, screeding, and <br />bull floating or darbying concrete but before float finishing. <br />D. Begin curing after finishing concrete but not before free water has disappeared from concrete <br />surface. <br />E. Curing Methods: Cure concrete by moisture curing, moisture-retaining-cover curing, curing <br />compound, or a combination of these as follows: <br />1. Moisture Curing: Keep surfaces continuously moist for not less than seven days with the <br />following materials: <br />a. Water. <br />b. Continuous water-fog spray. <br />c. Absorptive cover, water saturated and kept continuously wet. Cover concrete <br />surfaces and edges with 12-inchlap over adjacent absorptive covers. <br />2. Moisture-Retaining-Cover Curing: Cover concrete surfaces with moisture-retaining cover, <br />placed in widest practicable width, with sides and ends lapped at least 12 inches, and sealed <br />by waterproof tape or adhesive. Immediately repair any holes or tears occurring during <br />installation or curing period, using cover material and waterproof tape. <br />3. Curing Compound: Apply uniformly in continuous operation by power spray or roller <br />according to manufacturer's written instructions. Recoat areas subjected to heavy rainfall <br />within three hours after initial application. Maintain continuity of coating, and repair <br />damage during curing period. <br />3.9 PAVING TOLERANCES <br />A. Comply with tolerances in ACI 117and as follows: <br />1. Elevation: 3/4 inch. <br />2. Thickness: Plus 3/8 inch, minus 1/4 inch. <br />3. Surface: Gap below 10-feet-long; unleveled straightedge not to exceed 1/2 inch. <br />4. Joint Spacing: 3 inches. <br />5. Contraction Joint Depth: Plus 1/4 inch, no minus. <br />6. Joint Width: Plus 1/8 inch, no minus. <br />7. Alignment of Tie-Bar End Relative to Line Perpendicular to Paving Edge: 1/2 inch per 12 <br />inches of tie bar. <br />8. Lateral Alignment and Spacing of Dowels: 1 inch. <br />9. Vertical Alignment of Dowels: 1/4 inch. <br />10. Alignment of Dowel-Bar End Relative to Line Perpendicular to Paving Edge: 1/4 inch per <br />12 inches of dowel. <br />DocuSign Envelope ID: 7D9ACD4F-8F6C-42B6-9ADB-C60032DB6D03