specifications - FAACO - Federal Aviation Administration Contract ...

FTWIC-2235June, 2009During periods of high temperature and/or low humidity, take extreme care in finishingthe slabs to eliminate initial shrinkage cracks. Following the initial set of concrete, butwhile the concrete is still "green", continue to finish as required to remove shrinkagecracks which may occur. In hot, dry weather, keep a cement finisher on the job followingnormal finishing operations for a sufficient length of time to insure the removal of initialshrinkage cracks.3.13 VERTICAL SURFACES FINISHES:A. Forms for walls, columns and sides of beams and girders shall be removed as specified inSection 03100, CONCRETE FORMWORK. Patch, repair, finish and clean concreteafter form removal. Finish concrete within seven (7) days of form removal. Cureconcrete as finishing progresses.B. Air voids, for all types of finishes, are defects and shall be removed by rubbing orpatching.C. VERTICAL SURFACE FINISH SCHEDULE:TYPE OF FINISHFORM FINISHESLOCATION1. NO FINISH Concrete surfaces not exposed to view up to 1 footbelow grade.2. LIGHT SANDBLAST All concrete surfaces exposed to view to 1 footFINISHbelow grade. Fence post and panels light bollards.D. NO FINISH:No finish is applied to surfaces which are not visible from the inside or outside of thecompleted structure (i.e. back of retaining walls below embankment, etc.). After formsare removed, repair or patch tie holes and defects. Otherwise, no finish is required.E. LIGHT SANDBLAST FINISH:Surfaces to receive a light sandblast finish shall first receive a smooth rubbed finish.Blast the concrete surface with an abrasive (sand or grit) until the aggregate is in uniformrelief. The depth of penetration shall be sufficient to remove only the surface mortar.Prepare a 4' x 8' panel for the Contracting Officer's review. Subsequent sandblastfinishing shall match the sample precast panels.3.14 NORMAL SHRINKAGE GROUTING:A. Prior to grout application, thoroughly clean the surface of all foreign matter and wetdown. Thoroughly clean the foundation and the forms set in place and securely anchor,with holes or cracks in forms caulked with rags, cotton waste or dry sand mixture toprevent the loss of grout. The necessary materials and tools shall be on hand beforestarting grouting operations. Concrete shall be damp when the grout is poured, but shallnot have excess water to dilute the grout.03300-25