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B. As soon as the forms have been stripped and the concrete surfaces exposed, fins and other projections shall be removed, recesses left by the removal of form ties (except where ties are left in place during sandblasting) shall be filled and surface defects which do not impair structural strength shall be repaired. Clean all exposed concrete surfaces and adjoining work stained by leakage of concrete, to approval of the Engineer. C. Immediately after removal of forms remove plugs and break off metal ties as required by Paragraph 3.06. Holes are then to be promptly filled upon stripping as follows: Moisten the hole with water, followed by a 1/16 inch brush coat of neat cement slurry mixed to the consistency of a heavy paste. Immediately plug the holes with 1 1.5 mixture of cement and concrete sand mixer slightly damp to the tough (just short of "balling "). Hammer the grout into the hole until dense, and an excess of paste appears on the surface in the form of a spider web. Trowel smooth with heavy pressure. Avoid burnishing. D. Rub lightly with a fine carborandum stone at an age of 1 to 5 days if necessary to bring the surface down with the parent concrete. Exercise care to avoid damaging or straining the virgin skin of the surrounding parent concrete. Wash thoroughly to remove all rubbed matter. 1 06/05 03300 -12 03 -41383 E. Defective concrete and honeycombed areas shall be chipped reasonably square and at least 1 inch deep to sound concrete by means of hand chisels or pneumatic chipping hammers. Irregular voids or surface stones need not be removed if they are sound, free of laitance, and firmly embedded in the parent concrete, subject to Engineer's final inspection. If ' honeycomb exists around reinforcement, chip to provide a clear space at least 3/8 inch wide all around the steel. For areas less than 1 1/2 inch deep, the patch may be made in the same manner as described above for filling for tie holes, care being exercised to use adequately dry (non - trowelable) mixtures and to avoid sagging. Thick repairs will require build -up in successive 1 1/2 inch layers on successive days, each layer being applied (with slurry, etc.) as described above. To aid strength and bonding of the multiple layer repairs, the Engineer may order the use of Embeco non - shrink, metallic aggregate by the Master Builders Company, Cleveland, OH or Ironite by Fox Industries, Madison IL as an additive as follows: Material Volumes Weights Cement 1.0 1.0 Embeco 0.15 0.25 Sand 1.5 1.5 F. For very heavy (generally formed) patches; the Engineer may order the addition of pea gravel to the mixture and the proportions modified as follows: Material Volumes Weights Cement 1.0 1.0 Embeco 0.2 0.33 ' Sand 1.0 1.0 Pea Gravel 1.5 1.5 iG. In cases where the Embeco is employed in multiple patches and a rusty finish is not desired on the surface, such as exposed faces of walls, etc., the final layer (or at least the final 1/2 inch) shall be composed of the 1 1.5 grout without Embeco. After hardening, rub lightly as described above for form tie holes. 1 06/05 03300 -12 03 -41383