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DocuSign Envelope ID:AOF53191-262C-4CB2-B674-9AB9C758A904 <br /> 4. Curing and Sealing Compound:Apply uniformly to floors and slabs indicated in a continuous <br /> operation by power spray or roller according to manufacturer's written instructions.Recoat areas <br /> subjected to heavy rainfall within three hours after initial application.Repeat process 24 hours <br /> later and apply a second coat.Maintain continuity of coating and repair damage during curing <br /> period. <br /> 3.11 CONCRETE SURFACE REPAIRS <br /> A. Defective Concrete:Repair and patch defective areas when approved by Owner.Remove and replace <br /> concrete that cannot be repaired and patched to Owner's approval. <br /> B. Patching Mortar:Mix dry-pack patching mortar,consisting of one part portland cement to two and onehalf <br /> parts fine aggregate passing a No. 16 sieve,using only enough water for handling and placing. <br /> C. Repairing Formed Surfaces: Surface defects include color and texture irregularities,cracks,spalls,air <br /> bubbles,honeycombs,rock pockets,fins and other projections on the surface,and stains and other <br /> discolorations that cannot be removed by cleaning. <br /> 1. Immediately after form removal,cut out honeycombs,rock pockets,and voids more than 1/2 inch <br /> in any dimension to solid concrete.Limit cut depth to 3/4 inch.Make edges of cuts perpendicular <br /> to concrete surface. Clean,dampen with water,and brush-coat holes and voids with bonding <br /> agent.Fill and compact with patching mortar before bonding agent has dried.Fill form-tie voids <br /> with patching mortar or cone plugs secured in place with bonding agent. <br /> 2. Repair defects on surfaces exposed to view by blending white portland cement and standard <br /> portland cement so that,when dry,patching mortar will match surrounding color.Patch a test area <br /> at inconspicuous locations to verify mixture and color match before proceeding with patching. <br /> Compact mortar in place and strike off slightly higher than surrounding surface. <br /> 3. Repair defects on concealed formed surfaces that affect concrete's durability and structural <br /> performance as determined by Owner. <br /> D. Repairing Unformed Surfaces: Test unformed surfaces,such as floors and slabs,for finish and verify <br /> surface tolerances specified for each surface. Correct low and high areas. Test surfaces sloped to drain <br /> for trueness of slope and smoothness;use a sloped template. <br /> 1. Repair finished surfaces containing defects. Surface defects include spalls,popouts,honeycombs, <br /> rock pockets,crazing and cracks in excess of 0.01 inch wide or that penetrate to reinforcement or <br /> completely through unreinforced sections regardless of width,and other objectionable conditions. <br /> 2. After concrete has cured at least 14 days,correct high areas by grinding. <br /> 3. Correct localized low areas during or immediately after completing surface finishing operations by <br /> cutting out low areas and replacing with patching mortar.Finish repaired areas to blend into <br /> adjacent concrete. <br /> 4. Correct other low areas scheduled to receive floor coverings with a repair underlayment.Prepare, <br /> mix,and apply repair underlayment and primer according to manufacturer's written instructions to <br /> produce a smooth,uniform,plane,and level surface.Feather edges to match adjacent floor <br /> elevations. <br />