1902Quality Control Program for Precast Concrete Products

- QUALITY CONTROL PROGRAM FOR PRECAST CONCRETE PRODUCTS QUALITY CONTROL PROGRAM FOR PRECAST CONCRETE PRODUCTS

1902.1DESCRIPTION

This specification covers precast concrete pipe, end sections, inlets, manholes, boxes, and related concrete accessories. This specification does not apply to prestre ssed concrete beams or slabs, retaining wall panels, or temporary barriers.

1902.2REQUIREMENTS

certifications available at the precast production site.

concrete pipe). Use fly ash from a source prequalified under SECTION 2004. Obtain the Engineer’s approval before substituting fly ash for Type III Cement. Mix designs containing fly ash must be approved for each plant by using Kansas Test Method KTMR-29, “Wetting and Drying Test of Steam Cured Reinforced Concrete Pipe with Fly Ash.” If the mixture complies with the requirement, the producer and the KDOT plant inspect ors will be notified in writing. Preliminary approval will be given for mixtures at 150 days based on satisfactory test performance of KTMR-29. Contact the Bureau of Construction and Materials for information, and to make arrangements for testing. Alternatively, provide the results of ASTM C 1567 mortar expansion tests, using the mix design’s materials at their designated percentages. Provide a mix with a maximum expansion of 0.10% at 16 days after casting. If any of the sources of Cement, Fly Ash, or Aggregat e are changed in the future, repeat the testing or reporting procedures for the new mix design, as described in this subsection. Make all test results, certifications, and approval letters available for review at the production site.

shown in DIVISION 1100 of the Standard Specifications except that the gradation requirements do not apply. Also, update aggregate producer's certifications at 6-month intervals and when aggregate source changes are made. Make these certifications available at the precast production site.

precast production site.

applicable. Make certifications for steel reinforcement available at the precast production site. All steel components utilized in the products, reinforcing and structural must comply with DIVISION 1600.

complying with either AASHTO M 170 for round pipe, AASHTO M 206 for arch pipe or AASHTO M 207 for elliptical pipe with the following additions or deletions:

Class A-II or stronger arch pipe.

pipe and arch pipe will be shown in the Contract Documents. Pipe having larger diameters or waterway areas may be considered provided the Engineer approves any substitutions. The nominal waterway areas for various sizes of arch pipe are as shown in AASHTO M 206 and for various sizes of elliptical pipe are as shown in AASHTO M 207.

After placement, fill lift holes with a suitable concrete mortar, unless directed otherwise by the Engineer.

Class HE-II pipe, as applicable. Bevel to comply with the dimensions shown on the Contract Documents.

steel area and the workmanship requirements of this specification for Class II, Class A-II or Class HE-II pipe, as applicable. - QUALITY CONTROL PROGRAM FOR PRECAST CONCRETE PRODUCTS

fill lift holes with a suitable concrete mortar, unless directed otherwise by the Engineer.

storm water drainage complying with the KDOT approved shop drawings, including reinforcement, absorption, and concrete strength.

sanitary sewer drainage complying with the KDOT approved shop drawings and ASTM C 478.

1902.3TEST METHODS

be applied to procedures referenced in this specification.

precision statement for field conditions from ASTM C-39.

without special calibration, in the following conditions: • Slump ≤ 2 inches. • A mid-range or high-range water-reducer is used. • An air-entraining agent other than a vinsol resin is used. • Non-plastic concrete such as commonly used in the manufacture of pipe and concrete masonry units.

1231, “Use of Unbonded Caps in Determination of Compressive Strength of Hardened Concrete Cylinders.”

Materials and Aggregate (Accelerated Mortar-Bar Method).”

with Fly Ash.”

each mix design of a producer. The five lot moving average will apply to each mix design.

a minimum of 2 cylinders for shipping strength at the same age. Attain a minimum of 80 percent of the specified 28-day compressive strength for the product on each cylinder before shipping. These products are still subject to the requirements of this section and final approval at the project site. Note in the monthly report which products are shipped after 28 days of age, therefore not requiring shipping strength data. When shipping strength cylinders are utilized, a minimum of 1 set is to be produced at the same time period and from the same concrete batch as the 28-day comp ressive strength cylinders. Additional shipping strength cylinders may be produced at other times from different concrete batches and tested if desired. Submit all shipping strength data to KDOT and provide availability to the inspector at the production site.

sampling and testing for all producers are to be certified by ACI, or a KDOT approved equivalent, in the appropriate method(s) of sampling and testing, or the laboratory must be AASHTO accredited. Provide copies of the certifications to KDOT. Notify KDOT within 2 months of any changes in certification status or QC testing personnel. - QUALITY CONTROL PROGRAM FOR PRECAST CONCRETE PRODUCTS

sampling and testing for KDOT, with all associated costs paid for by the producing facility. All laboratories performing verification sampling and testing must be accred ited by AASHTO for all the accreditation available test methods shown in subsection 1902.3 . In addition, all laboratories performing verification sampling and testing must be approved by KDOT, and must report all test results directly to KDOT.

1902.4PRODUCER PREQUALIFICATION

products. Provide 28-day compressive strength test data fo r all 5 lots. Allow KDOT to sample and test 1 of the 5 lots. This sample will be a split sample, with KDOT and Producer testing essentially the same product. The maximum variation between the average of the Producer’s 5 lots and KDOT’s test results is 10%.

facility are produced under a Quality Control Program. Present a Quality Control Plan to the Bureau Chief of Construction and Materials for evaluation and disposition. The plan must provide the following information as the minimum requirements: • Name and location of the producer's facility. • Name, telephone number, level of authority (organizational chart), and qualifications of the persons and alternates directing quality control at the facility. One of these individuals must be present during production at the facility. • The name and location of the laboratory, whether internal or external to the facility, conducting the quality control testing for th e producer. A listing of any accreditatio n of the laboratory as well as the frequency of NIST traceable equipment calibrations is required. • Except as described in subsection 1902.4a(4), a lot is defined as the production from each mix design during the 7 consecutive day period beginning Sunday and ending Saturday of each week. Test 1 lot from each mix design used at the facility during th is 7-day period. Lot size is 7 consecutive days regardless of the size or type of product or whether the mix is used only once during that 7-day period or each of the 7 days. • List the QC tests to be performed, including which tests are used for shipping strength. Define the method for obtaining random samples for each test and the number of samples to be tested per lot. • The frequency of submitting quality control summary reports. This is not to be less than 1 report per month.

prequalified precast product sources maintained by the Bureau of Construction and Materials.

or do not continually provide products to KDOT may base their lots on a per unit basis, not to exceed 1 month. Producers of manholes, inlets, boxes and other project specific products that choose this option must notify the Bureau of Construction and Materials when producing K DOT products. KDOT may also choose to decrease the frequency of verification sampling, testing and production monitoring for any Producer.

strength, tX ; the n - 1 weighted standard deviation of the 5 test values used to determine the moving average, St; the quality index, QL; and the associated percent within limits (PWL) as referenced in the Terminology and Definitions. Notify KDOT of changes in mix designs, concrete materials sources, mixing equipment, or sources of concrete. Changes that significantly affect the control charts may constitute a new mix design and therefore require a new five lot moving average. Produce 5 successive lots complying with the minimum strength requirements for each new mix design. Selection of the production lot or test number, t is im portant since it determines the 5 test moving average. Since t is an integer, it is suggested that for the first lot, set t = 1, increment by 1 for each successive lot. A producer, at their option, may impose a more stringent quality control requirement than the five lot moving average. Inform KDOT as to the frequency of qu ality control testing, the PWL, the production quantity - QUALITY CONTROL PROGRAM FOR PRECAST CONCRETE PRODUCTS represented by the test or tests, other types of contro l monitoring such as attributes, variables, tracking and traceability methods, etc. The Producer and KDOT must mutually agree upon this program. The frequency of sampling and testing may be decreased with the approval of KDOT if proficiency in maintaining the quality control of the products is demonstrated to the satisfaction of KDOT.

percent of the specified minimum 28-day compressive strength. Clearly mark this material to prevent it from being included in a KDOT project and store it separately from the approved material.

compressive strength for the 5 lot moving average. The Lower Spec Limit (LSL) for each product is that product's required 28-day compressive strength. Notify KDOT i mmediately whenever the 5 lot moving average falls below 90 PWL, and comply with the following. Produce 5 successive lots complying with the minimum strength requirements as agreed upon by KDOT and the Producer, and provide documentation that corrective action has been taken and that compliance has been reestablished.

all inventories. Clearly mark all prod ucts not intended for KDOT use. Main tain traceability of all products shipped to KDOT projects.

requirements for the project.

samples will be taken at a minimum of once every 5 lots for each product. This may include, but is not restricted to, any combination of cylinders, core samples, and, for pipe, 3-edge bearing tests. The same statistical parameters ( tX ,St; and PWL) will be developed from th e verification test data of the cy linders. Under normal conditions, no more than 10 pieces of pipe per year will be tested to u ltimate strength when the 3-edge bearing test is used for verification testing.

quality control tests through the F and t statistical test to determine if they represent the same population. Continual deviations will be rectified with the Producer.

of Prequalified Status if not corrected or eliminated after notification.

QC/QA and Statistical Analysis.

 Clear and consistent identification of each mix design and test samples. Use only 1 producer defined lower specification limit for each mix design.  The date the sample, product, or cylinders were produced and the dates tested for both shipping strength and 28-day compressive strengths of laboratory cured cylinders. Include documentation when products are not shipped before 28 days, therefore waving the shipping strength requirements.  The load at failure, compressive strength, applicable correction factor, and corrected strength, for each individual sample tested as per subsection 1902.3c.  The statistical analysis of this data as described in subsection 1902.4b(1) and the optional control charts.

industry.

Further delinquent reports may cause permanent loss of Prequalified Status.

production site. Test reports are to bear the names and signatures of the certified technicians or representative of the laboratory conducting the sampling and testing. For pre cast facilities that are performing their own QC testing, actual data records are to be initialed by the certified t echnicians conducting the testing. Make available for inspection the shipping records for KDOT projects. - QUALITY CONTROL PROGRAM FOR PRECAST CONCRETE PRODUCTS

1902.5BASIS OF ACCEPTANCE

Delete the basis of acceptance in AASHTO M 170 , AASHTO M 206 and AASH TO M 207, and replace with the following:

damage, fit and other visual defects, and disposition when delivered to the project site.

production of all product delivered to the job site comp lies with all provisions of the Buy America Act. See subsection 106.1c. for a definition of “Buy America” materials.