SUPPLEMENTAL SPECIFICATION 898 QC/QA CONCRETE FOR STRUCTURES March 23, 2009 PROCEDURES FOR PROCESSING and CMS DATA ENTRY OF QC AND QA CYLINDERS

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1 A. QC (Quality Control) CYLINDERS Create ONE Sample ID in CMS for each LOT of concrete (see Attachment A for Lot & Sublot definition) Copy [F7] the MATERIAL SAMPLE screen to create as many suffixes as needed for each days production 1. The Sample Origin is the District number of the District creating the Sample ID 2. The Personnel Id identifies the person creating the Sample ID. Enter your SS number or use [F4] list and select name. The SS number will not be displayed when typing or displayed after the SID is created. 3. The Nbr of Mult Smpl is automatically filled in when a suffix is created. 4. The Type of Inspection is CTL (job control) for the QC samples 5. The Date Sampled is the date that the concrete is placed, not the date that the Sample ID is created. (If you have copied the screen, using the F7 key, for another lot make sure to change the date before adding the JMF number to the next screen The date is locked in and can only be corrected by the DET or OMM.) 6. The Related Sample ID field can be left blank for the QC samples. 7. The Test Code is automatically filled in when the material code is entered. 8. The Nbr of Proj/PO Ref field is automatically filled in with the number of references assigned to the Sample ID 9. The QC/QA Job Mix Formula (JMF) is specific to the ready mix company. The JMFs have been assigned to one location for each company. The Producer / Supplier Code (P/S Cd) location that ends with a Q is the plant location with the JMF assignments. Once the JMF is approved by the Office of Materials Management (OMM), it may be supplied by any of the company s plant locations. The P/S Cd field is for the Plant Location with the Q designation The Plant Location actually supplying the concrete should be entered into the Mix Plant field. 10. The Desc 1, Desc 2, Desc 3 Description fields are left blank for OMM to use. OMM assigns internal lab tracking numbers and enters them into these fields. 11. The Rep Qty field is for the quantity of concrete for the items to be placed that day 12. The Nbr of Items field is left blank 13. The Proj Asgn Qty: field will automatically fill in when material is assigned ***ONLY assign material to the QC cylinder Sample ID s.not the QA sample ID s 1

2 14. The Consign To field should indicate the name of the Contractor 15. The Sampled From field should indicate the Project Number Indicate in the official format (060114) rather than (114-06) 16. The Resp Loc (Responsible Location) field indicates the office that has authority for the Sample ID The responsible location stays with the District for QC samples. 17. Dates Date Shipped should indicate the date that the cylinders were taken from the project in the field. This should be within 48 hours after the concrete is placed according to ASTM and ACI specifications Date Received field should be left blank Test Start field is date of placement +4 weeks Est Compl is date of placement +5 weeks. This gives the Contractor a week to provide the test results to the project B. Use F11 key and Enter the TE-45 information Once any information is entered on this screen the Date Sampled, Material Code and P/S code are locked in on the front screen. If you have used [F7] to Copy make sure you have changed the Date and that all other information is correct before entering any data in this screen. JMF The Job Mix Formula (JMF) number should be indicated on the Batch Ticket. The JMF can be verified verses the sources of material by pressing the [F7] key (JMF) from the QC/QA PCC INSPECTORS DAILY REPORT screen. 2

3 Do not use the State General Material P/S code on this screen for: Cement P/S, Fly ash P/S, GGBF Slag P/S or Micro Silica P/S. Indicate the Location the concrete is being placed C. Use [F5] PCPST key and enter all of the information for the cylinder set (s) 1. The sampling, handling and testing of the concrete specimens is performed by the Contractor s Lab. The concrete specimens are to be handled in strict accordance with applicable ASTM and ACI standards. 2. Air, Slump, Temperature, Time, Lot/Sublot, Specimen Number, Date, Age, and Strength information is to be reported back on Table 9 of the SS-898 Specification (July 21, 2006 Revision) by the Contractor within 5 business days after the strength tests are conducted by the Contractor s lab. 3. Indicate that the test specimens are cylinders by typing a Y in the cylinder field and an N in the beam field. 4. SS-898 revisions prior to 7/21/06 require permeability testing. The 7/21/06 revision does not require permeability testing as part of the QC testing. 5. Include the name of the private lab that performed the tests in the Certified Lab Name field. 6. The data should be entered, by the District, on this screen in a timely manner. 3

4 D. APPROVAL or NOT APPROVAL of SID Once the test results for that day s production are and entered into the test screens, the sample should be approved (APPR) or not approved (NAPP) in the Test Result field and Authorized by the person appointed to do so via District policy. Follow the guidelines in Attachment B when results are reported that do not meet the Specification. Determine pay factor according to requirements in SS-898. Determine pay factor according SS , if the strengths are unacceptable refer to SS for resolution. 4

5 A. QA (Quality Assurance) CYLINDERS A set of QA cylinders is taken from sublots determined by the Engineer 4 cylinders are made for QA Testing All 4 of the QA samples are to be made by ODOT personnel Take the sample from the same load as the corresponding QC sample Also test the air, slump and temperature of the concrete and compare with the results of the QC tests 1. The Contractor s lab takes possession of the QA cylinders. They handle and cure them in the same manner as the QC cylinders, until 14 days of age. At that time, two cylinders are delivered to the Columbus Test Lab (OMM) who will continue the curing until 28 days of age, when they are tested. 2. Since the actual specimens are under the control of the Contractor s lab, it is important that identifying information be given to them, by the project, to identify the specimens. The Project Number, Sample ID, Specimen Number and Date Made should be given to the Contractor s lab on the day of the placement for identification of the QC and QA samples. Samples should be set up in the Construction Management System (CMS) prior to the concrete placement, and a TE-31 should be given to the Contractor s lab at time of the cylinder pick-up and each cylinder must have a completed TE-10 tag. 5

6 3. Use the QC guidelines for setting up an entirely new Sample ID in CMS so that the information is reported consistently, with the following exceptions: Inspection Type must be QA Enter in Related Sample ID field the related Sample ID of the QC DO NOT. DO NOT assign material to the QA Sample ID When numbering specimens use the prefix T (Transportation) for the specimens that the ODOT Test Lab will break and use the prefix C for the specimens the Contractor s Lab will break. Make 2 (two) QC/QA PCC AIR/SLUMP/YIELD/STRENGTH TEST screens. One for the set of specimens to be broken by ODOT Test Lab (OMM) One for the set of specimens to be broken by the Contractor s Lab. Transfer authority of the Sample ID to OMM (Resp Loc = TL and Lab = PC) ODOT-OMM will break two QA cylinders at 28 days of age, record results, and return authority of the Sample ID back to the District/Project. Date Received, Test Start and Est Compl dates will be filled in by OMM 4. Below are examples of completed QA Sample ID screens: 6

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9 5. The District/Project must enter the Contractor s QA strength results from Table 9 of SS-898, when received at a later date. Compare the ODOT-OMM QA strength results and the Contractor s QA strength results to verify they are within 500 PSI of each other. The District/Project should also compare the QA strength results with the related sample QC results from the private lab. These results should also be within 500 PSI. If all are within 500 PSI, approve and authorize the QA Sample ID. If they are not within 500 PSI investigate according to SS Then, Approve or Not Approve the Sample ID s, as required, by recording APPR or NAPP in the test result field. 9

10 ATTACHMENT A A. LOT AND SUBLOT DIVISION: 1. A LOT is all concrete of the same design requirements (class). A single lot may consist of several structural elements (footer, pier, abutment ) and be covered by several reference numbers. a. Typically the classes are divided into two areas, the Substructure (QSC1) and the Superstructure (QSC2). Occasionally there may be concrete with special requirements (QSC3). There should be one lot for each class of concrete specified. i. An exception to the one class - one lot rule is when the concrete is slip-formed. The Contractor may elect to have the slip-formed concrete considered as a separate lot from the rest of the concrete of the same class that is not slipformed. b. If there are multiple structures on a project, each structure should have it s own lots 2. A SUBLOT is the division of the lot into 50 yd 3 or less for sampling and testing purposes. The Contractor proposes the sublot divisions in the Quality Control Plan (QCP) for the Engineer s approval. a. QC cylinders is to be taken from every sublot i. Three (3) QC cylinders are made a. Two (2) cylinders are tested at 28 days and the individual strengths and average of the two strengths are reported. 1) If the strengths of the two individual cylinders do not fall within a range of 8%, the 3 rd cylinder is tested and reported with the closer of the first two results (ASTM C39). 2) If the strengths of the first two individual cylinders are within a range of 8%, the 3 rd cylinder can be discarded. 10

11 ATTACHMENT B Consider the following when approving or not approving the concrete in CMS. A. Compressive Strength: 1. If the compressive strength of the QC specimens is.88 f c ( Table 1) or greater, the QC sample should be approved as far as strength is concerned. 2. If the compressive strength of the QC specimens is less than.88 f c, evaluate the concrete in accordance with a. Concrete strength results are found to be correct:: i. Sample should be not approved NAPP ii. Describe evaluation and results in the remarks b. Concrete strength results are found to be incorrect and strength is higher than indicated and above.88 f c: i. Sample should be approved APPR ii. Describe evaluation and results in the remarks B. Air Content For concrete placed that has far below or above the limits of Table 2, use the following guidelines for acceptance 1. Concrete that is placed into the structure that does not meet the requirements, in the plastic state, should be not approved NAPP a. To determine if the concrete should remain in place or removed and replaced, follow the guidelines in SS b. Concrete allowed to remain in-place should be paid at 75% c. Concrete that is removed and replaced should be retested and re-evaluated for acceptance and payment on the new placement. i. Disregard the results of the removed concrete for payment. C. Permeability Concrete placed under 898 revision 7/21/06 and after no permeability test is required. Concrete placed under SS898 revisions prior to 7/21/06, Permeability is to be reported according to the Engineers instructions. 1. Do not base approval or payment on permeability. Do report value in the appropriate field in CMS. a. Notify DET of results over DET should then notify OMM of results. 11