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II . .., . 346-9 Acceptance Sampling and Testing. 346-9.1 General: Perform plastic properties test as per 346-8 and cast a set of three QC cylinders for each LOT of structural concrete incorporated into the project. Take these acceptance samples randomly for each LOT as determined by a random number generator (acceptable to the Department). The Department will independently perform plastic properties test and cast a set of verification cylinders from a separate sample from the same load of concrete as the Contractor's QC sample. For each LOT verified by the Department, cast one additional cylinder from the same sample, and identify it as the QC "hold" cylinder. The Department will also cast one additional "hold" cylinder from each verification sample. Provide curing facilities for initial curing that have the capacity to hold all QC, Verification, and Independent Verification cylinders simultaneously. All cylinders will be clearly identified. Deliver the QC samples to the final curing facility in accordance with ASTM C 31 [ASTM C 31 M]. At this same time, the Department will deliver the verification samples to their final curing facility. Test the QC samples for compressive strength at the age of 28 days in a laboratory meeting and maintaining at all times the qualification requirements listed in 6-9. The QC testing laboratory will input the compressive strength test results into the Department's sample tracking database within 24 hours. When the QC testing laboratory cannot input the compressive strength test results into the Department's sample tracking database within 24 hours, the QC testing laboratory will notify the Verification testing laboratory within 24 hours of breaking the cylinder and provide the Verification testing laboratory the compressive strength test results. Ensure the compressive strength results are input into the Department's sample tracking database within 72 hours of determining the compressive strength of the cylinders. The Department will average the QC and Verification compressive strength test data and based on this average at 28 days determine the Comparison Criteria as shown in Table 8. When the difference between QC and Verification are less than or equal to the Comparison Criteria, the QC data is verified. When the difference between QC and verification data exceeds the Comparison Criteria the Engineer will initiate the resolution procedure in accordance with 346-9.5. The QC and Verification laboratories will transport their own hold cylinder to the resolution testing laboratory within 72 hours after the Engineer notifies the Contractor that a resolution is required. . ,.., . ..., . n . ,.., . " . .-, . .., . .., ,., . .., . 1""'1 Table 8 Range of Average Compressive Strength Comparison Criteria Less than 3500 psi [23 MPa] 420 psi [2.9 MPa] 3,501 - 4,500 psi [23 - 31 MPa] 590 psi [4.0 MPa] 4,501 - 6,500 psi [31 - 45 MPa] 910 psi [6.3 MPa] 6,501 - 8,500 psi [45 - 59 MPa] 1,275 psi [8.8 MPa] Greater than 8,500 psi [59 MPa] 1,360 psi [9.4 MPa] . " . .., . ,., r"'1 346-9.2 Sampling Frequency for Quality Control Tests: As a minimum, sample and test concrete of each design mix for water to cementitious materials ratio, air content, temperature, slump and compressive strength in accordance with Table 9. The Engineer will randomly verify one of every four consecutive LOTs of each design mix based on a random number generator, and may perform additional Independent Verification tests. All QC activities, calculations, and inspections . . .... . r"'I 09/09 01000-103 03-4122.F .