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I I I I I I I I I I I I I I I I I I II 3.11 04/08 B. When the tests on control specimens of concrete fall below the required strength, the Engineer will permit check tests for structure in accordance with ASTM Methods C42 and C39. In case of failure of the latter, the Engineer, in addition to other recourses, may require, at the Contractor's expense, load tests on anyone of the slabs, beams, and columns in which such concrete was used. Test need not be made until concrete has aged 60 days. C. Slabs or beams, under load test, shall be loaded with their own weights plus a super-imposed load of 2 times design live load. The load shall be applied uniformly over portion being tested in approved manner, and left in position for 24 hours. The structure shall be considered satisfactory if deflection "D" in feet, at end of 24-hour period does not exceed value: D equals 0.001 (L x L)/t in which "L" is span in feet, "t" is depth of slab or beam in inches. D. If deflection exceeds "D" in the above formula, the concrete shall be considered faulty unless within 24 hours after removal of the load, slab or beam under test recovers at least 75% of observed deflection. E. Should the strength of test cylinders fall below 60% of the required minimum 28 day strength, the concrete shall be rejected and shall be removed and replaced. PATCHING AND REPAIRS A. It is the intent of these Specifications to require that forms, mixture of concrete and workmanship shall be such that concrete surfaces, when exposed, will require minimal finishing as specified in Paragraph 3.05 above. 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 Oust short of "balling"). 03300-15 06-5723