Laserfiche WebLink
� <br /> ' A. Inspection: Before placing concrete, inspect aBd coFnplete formwark installation, <br /> reinforcing steel, and items to be embedded or cast in. Notify ofher trades to permit <br /> installation of their work. <br /> ' B. General: Comply with ACI 304, "Guide for Measuring, Mixing, Transporting, and <br /> Placing Concrete,"and as specified. <br /> ' C. Deposit concrete cantinuousIy ar in layers of such thickness that no new concrete will be <br /> placed on concrete that has hardened snfficiently to cause searns or planes of vveakness. <br /> If a section cannot be placed continuously, provide construction joints as specified. <br /> ' Deposit concrete to avoid segregation at its final location. <br /> D. Placing Concrete in Forms: Deposit concrete in forms in horizontal layers no deeper than <br /> 24 inches and in a manner to avoid incluaed construction joints. Where placement <br /> ' consists of several layers, place each layer while preceding layer is still plastic to avoid <br /> cold joints. <br /> ' 1. Cansolidate placed conerete by mechanical vibrating equipment supplemented by <br /> hand-spading, rodding, or tamping. Use equipment and procedures for <br /> consolidation of conerete complying with ACI 309. <br /> , E. Placing Concrete Slabs: Deposit and consolidate conerete slabs in a con�inuous <br /> operation, within limits of construc�ion joints, until completing placement of a panel or <br /> section. <br /> ' 1. Consolidate conerete during piacement operations so that conerete is thoroughiy <br /> worked around reinforcement,other embedded items and into corners. <br /> 2. Bring slab surfaces to correct level with a straiglrtedge and strike of� Use bull <br /> ' floats or darbies to smooth swface free of humps or hollows. Do not disturb slab <br /> surfaces prior to beginning finishing operatians. <br /> 3. Maintain reinforcing in proper position on chairs during concrete placetttent. <br /> ' F. Ho#-Weather Placement: When hot weather conditions exist that would impair quality <br /> and strength of concrete,place conerete complying witb ACI 30S and as specified. <br /> ' 1. Cool ingredients before mixing to maintain concrete temperature at time of <br /> placement to below 90 deg F (32 deg C). Mixing water may be chilied or <br /> chopped ice may be ased to control temperature,provided water equivaIent of ice <br /> , is caIculated to total amount of mixing water. Using liquid nitro�en to cool <br /> concrete is Contractor's option. <br /> 2. Cover reinforcing steel with water-soaked burlap if it becomes too hot, so that <br /> steel temperahue wiil not exceed the amhient air temperatut'e imraediately before <br /> ' embedding in concrete. <br /> 3. Fog spray forms, reinforcing steel, and subgrade just�before placing concrete. <br /> Keep subgrade moisture uniform without puddles or dry areas. <br /> ' 4. Use water-reducing retarding admix#ure when required by high temperatures,low <br /> hwnidity,or other adverse placing conditions,as acceptable to Architect. <br /> 3.6 FINISHING FORMED SURFACES <br /> , A. Rough-Formeci Finish: Provide a rough-formed futish on formed concrete surfaces nat <br /> exposed to view in the finished Work or concealed by other construction. This is the <br /> ' conerete surface having te�cture imparted by form-facing mat�erial use�d,with tie holes and <br /> defective areas repaired and patched,and fins and other projections exceeding 1/4 inch in <br /> height rubbed down or chipped off. <br /> ' B. Smooth-Formed Finish: Provide a smooth-formed finish on fornaed concrete surfaces <br /> exposed to view or to be covered with a coating material applied directly to concrete,or a <br /> covering material applied ciirectly to concrete,such as waterproofing,dampproofing, <br /> ' CONCRETE Page 5 of 8 <br />