Laserfiche WebLink
disappeared,or when concrete has stiffened sufficiently to permit operation of power-driven <br /> floats,or both. Consolidate surface with power-driven floats or by hand-floating if area is <br /> small or inaccessible to power units. Finish surfaces to tolerances of F(F) 18(floor flatness) <br /> and F(L) 15(floor levelness)measured according to ASTM E 1155. Cut down high spots <br /> and fill low spots. Uniformly slope snrfaces to drains. Immediately after leveling,refloat <br /> surface to a uniform,smooth,gra.nulaz texture. <br /> B. After floating,begin first trowel-finish operation using a power-driven trowel. Begin final <br /> troweling when surface produces a ringing sound as trowel is moved over surface. Consolidate concrete <br /> surface by fmal hand-troweling operation,free of trowel marks,uniform in texture and appearance,and fmish <br /> surfaces to tolerances of F(�20(floor flafiess)and F(L)17(floor levelness)measured according to ASTM <br /> E 1155. Grind smooth any surface defects that would telegraph througb applied floor covering system. <br /> C. Trowel and Fine Broom Finish: Where ceramic or quazry tile is to be installed with thin- <br /> set mortar,apply a trowel finish as specified,then immediately follow by slightly scarifying the surFace with <br /> a fine broom. <br /> 39 MISCELLANEOUS CONCRETE ITEMS <br /> A. Filling In: Fill in holes and openings left in concrete structures for passage of work by <br /> other trades,unless otherwise shown or directed,after work of other trades is in place. Mix,place,and cure <br /> concrete as specified to blend with in-place construction. Provide other miscellaneous concrete filling shown <br /> or required to complete Work. <br /> B. Curbs: Provide monolithic finish to interior curbs by stripping forms while concrete is l <br /> still green and by steel-troweling surfaces to a hard,dense fmish with corners,intersections,and terminations <br /> slightly rounded. <br /> C. Equipment Bases and Foundations: Provide machine and equipment bases and <br /> foundations as shown on drawings. Set anchor bolts for machines and equipment to template at correct <br /> elevations,complying with diagrams or templates of manufacturer fumishing machines and equipment. <br /> 3.10 CUNCRETE CURING AND PROTECTION � <br /> A. General: Protect fre.shly placed concrete from premature drying and excessive cold or hot <br /> temperatures. In hot,dry,and windy weather protect concrete from rapid moisture loss before and during <br /> finishing operations with an evaporation-control material. Apply according to manufacturer's instructions <br /> after screeding and bull floating,but before power floating and troweling. <br /> B. Start initial curing as soon as free water has disappeared from concrete surface after <br /> placing and finishing. Weather permitting,keep continuously moist for not less than 7 days. <br /> C. Curing Methods: Cure concrete by curing compound,by moist curing,by moisture- <br /> retaining cover curing,or by combining these methods,as specified. <br /> D. Provide moisture curing by the following methods: <br /> 1. Keep concrete surface continuously wet by covering with water. � <br /> 2. Use continuous water-fog spray. <br /> 3. Cover concrete surface with specified absorptive cover,thoroughly saturate cover with water, <br /> and keep continuously wet. Place absorptive cover to provide coverage of concrete surfaces <br /> and edges,with a 4-inch lap over adjacent absorptive covers. <br /> E. Provide moisture-retaining cover curing as follows: <br /> 1. Cover concrete surfaces with moisture-retaining cover for curing concrete,placed in widest <br /> Page 6 of 8 <br />