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1. Prepare standard 6" diameter concrete compression test cylinders in the <br />field in accordance with ASTM C31 - latest edition and C172 - latest <br />edition. The cylinder shall be delivered to the testing laboratory for <br />curing and testing in accordance with ASTM C31 - latest edition and C39 <br />- latest edition. <br />2. At least 1 set of test cylinders shall be made for each day's pour in excess <br />of 1 cubic yard for each type of concrete. If a day's pour exceeds 25 cubic <br />yards, 1 set of test cylinders shall be made for each additional 50 cubic <br />yards or fraction thereof. <br />3. Cylinder set consists of 4 cylinders, 3 for lab use and one for field control; <br />allow no damage to cylinders. <br />a. Mark cylinders with consecutive numbers, date cast, locations, <br />slump, air content, contractor name and project. <br />b. Keep cylinders at 60 degrees F. to 80 degrees F for first 24 hours. <br />c. After 24 hours, place filed control cylinder at placement location <br />under identical protection and curing procedures; transport <br />remaining three cylinders to laboratory. <br />d. Cylinders will be tested as follows: 1 cylinder at 7 days for <br />information and 2 cylinders at 28 days for acceptance. <br />4. The strength level shall be considered satisfactory so long as the averages <br />of all sets of 34 consecutive strength test results equal or exceed the <br />specified strength f'c and no individual strength test result falls below the <br />specified f'c by more than 500 psi. <br />5. In cases where samples have not been taken or tests conducted as <br />specified or the strength of the laboratory test cylinders for a particular <br />portion of the structure fails to meet the requirements of ACI 318, Section <br />4.8, for evaluation of concrete strength, the Architect/Engineer shall have <br />the right to order compressive and flexural test specimens taken from the <br />hardened concrete according to ASTM C42 - latest edition, load tests <br />according to ACI 318, Chapter 29 or such other tests as may be necessary <br />to clearly establish the strength of the concrete and such tests shall be <br />paid by the Contractor. <br />6. If test results do not achieve the required level, the Architect/Engineer <br />reserves the right to order the mix design changed to a lower water - <br />cement ratio so that the required strength level is achieved. <br />K. Slump tests: Provide slump tests taken by an independent laboratory. Take one <br />test of a first load of the day and one random load during the day. If a load falls, <br />reject the load and test each subsequent load of the day. <br />1.3 SUBMITTALS <br />A. Mix designs: <br />1. All mix designs shall be proportioned in accordance with Section 4.3 <br />(field experience) or Section 4.4 (trail batches) of ACI 318 - latest edition. <br />Submit proposed mix design within 20 days after Notice to Proceed and <br />include: <br />03300-2 <br />