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DocuSign Envelope ID: 313DA256 -1EDE- 4396- A716- 4C53B809027E <br />JERRY M. PASSMORE CENTER ADDITION AND RENOVATION <br />HILLSBOROUGH, NORTH CAROLINA <br />3. Correct localized low areas during or immediately after completing surface finishing operations <br />by cutting out low areas and replacing with patching mortar. Finish repaired areas to blend into <br />adjacent concrete. <br />4. Repair defective areas, except random cracks and single holes 1 inch or less in diameter, by <br />cutting out and replacing with fresh concrete. Remove defective areas with clean, square cuts <br />and expose steel reinforcement with at least 3/4 inch clearance all around. Dampen concrete <br />surfaces in contact with patching concrete and apply bonding agent. Mix patching concrete of <br />same materials and mix as original concrete except without coarse aggregate. Place, compact, <br />and finish to blend with adjacent finished concrete. Cure in same manner as adjacent concrete. <br />5. Repair random cracks and single holes 1 inch or less in diameter with patching mortar. Groove <br />top of cracks and cut out holes to sound concrete and clean off dust, dirt, and loose particles. <br />Dampen cleaned concrete surfaces and apply bonding agent. Place patching mortar before <br />bonding agent has dried. Compact patching mortar and finish to match adjacent concrete. Keep <br />patched area continuously moist for at least 72 hours. <br />E. Perform structural repairs of concrete, subject to Architect's approval, using epoxy adhesive and <br />patching mortar. <br />F. Repair materials and installation not specified above maybe used, subject to Architect's approval. <br />3.15 FIELD QUALITY CONTROL <br />A. Testing Agency: Owner will employ and pay for a qualified independent testing and inspecting <br />agency to sample materials, perform tests, perform inspections and submit test reports during <br />concrete placement. Sampling and testing for quality control may include those specified in this <br />Article. <br />B. Testing Services: Testing of composite samples of fresh concrete obtained according to <br />ASTM C 172 shall be performed according to the following requirements: <br />1. Testing Frequency: Obtain at least one composite sample for each 100 cu. yd. or fraction thereof <br />of each concrete mix placed each day. <br />a. When frequency of testing will provide fewer than five compressive - strength tests for each <br />concrete mix, testing shall be conducted from at least five randomly selected batches or <br />from each batch if fewer than five are used. <br />2. Slump: ASTM C 143; one test at point of placement for each composite sample, but not less <br />than one test for each day's pour of each concrete mix. Perform additional tests when concrete <br />consistency appears to change. <br />3. Air Content: ASTM C 231, pressure method, for normal- weight concrete; one test for each <br />composite sample, but not less than one test for each day's pour of each concrete mix. <br />4. Concrete Temperature: ASTM C 1064; one test hourly when air temperature is 40 deg F and <br />below and when 80 deg F and above, and one test for each composite sample. <br />5. Compression Test Specimens: ASTM C 31 /C 31M; cast and laboratory cure one set of five <br />standard cylinder specimens for each composite sample. <br />a. Two cylinders shall be broken at 7 and 28 days. The fifth cylinder shall be held in reserve <br />and broken at the direction of the structural engineer. <br />CAST -IN-PLACE CONCRETE 033000- 16 <br />