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D. At concrete with moist type cure,cover with moisture-proof covering.Remove and wet concrete as often as required to keep damp for entire curing period. Provide continuous curing with no dryouts during entire period. 3.7 QUALITY CONTROL TESTING DURING CONSTRUCTION A. Coordinate with ITL employed by the Owner to make,cure and determine strength of concrete test cylinders cast in field. Perform in accordance with ASTM C172-Method of Sampling Freshly Mixed Concrete,ASTM C31 -Method of Making and Curing Complete Test Specimens in Field and ASTM C39-Test Method for Compressive Strength of Cylindrical Concrete Specimens.Evaluation and acceptance of concrete shall be in accordance with Section 4.7 of ACI 318 with following exceptions: 1. Make 1 set of cylinders for each day's operation and each type of concrete where less . than 50 cubic yards is placed,plus additional set for each 50 cubic yards(or fraction thereof)over and above first 50 cubic yards of each type. Test sets shall consist of 4 cylinders with fourth cylinder to be field-cured specimen. For slabs placed when temperatures are expected to fall below 32 degrees F within 72 hours of placement cast in place(pop out)cylinders shall be used. These cylinders shall be placed close to corners and perimeter of pour. 2. Store field-cured cylinder as near as possible to location of concrete represented by sample and give cylinder,insofar as practicable, same protection and curing as adjacent concrete. Keep other 3 cylinders covered with plastic or wet burlap and in 60- 80 degrees F.temperature range for 24 hours,allowing no injury to cylinders. After this period,and prior to age of 48 hours, deliver 3 cylinders to laboratory for additional curing,taking care not to freeze,crack or damage specimens. 3. Deliver field-cured cylinder to laboratory at 28 days of age for testing to check adequacy of curing and protection as described in Article 4.7.3 of ACI 318. 4. Test other 3 cylinders,laboratory cured,as follows: 1 at 7 days of age for projecting probable 28 day strength and 2 cylinders at 28 days for acceptance of average strength as described in Article 4.7.1 of ACI 318. 5. If additional field cured specimens are required to verify early strength of concrete, contractor shall pay for additional testing. B. Determine slump of concrete in accordance with ASTM C143 - Standard Test Method for Slump of Portland Cement Concrete. Perform 1 test for each set of test cylinders. C. Determine air content of fresh concrete,when air content is specified,in accordance with ASTM C173 or ASTM C231. Where placement is by pump,air content shall be measured at location of placement. For concrete exposed to freezing and thawing, concrete from each truck shall be tested and concrete not meeting specified percentages shall not be placed. For interior concrete not exposed to freezing and thawing,such as lightweight concrete on metal decking,perform 1 test for each set of test cylinders. ADDENDUM#1 1607.001 -ORONO ICE ARENA(CP-2) Page 03300- 12