Agenda - Council - 06/27/2017 - Laserfiche WebLink

Home

SALT Schedule of Materials Control - Local Government Agency CERTIFIED READY -MIX CONCRETE, 2 of 2 The Prime Contractor is responsible to assure that all ready -mix concrete used is produced by an annually Certified Ready -Mix plant as detailed in Specification 2461.3F. Spec. I Test Type See page 1 of 2 Concrete Field Testing Rates Concrete Pavement Texture Compressive Strength (5-694.511) Standard cylinder size is 4 x 8, use 6 x 12 with aggregate greater than 1 1/4". Review 2461.3G.5 Test Methods and Specimens. Engineer Testing Rates ( 1 ) I Form I General Concrete Grades F, G, M, P, and R: 1 set of 3 cylinders per 300 yd3. Bridge Concrete Grades B, S, and Y: 1 set of 3 cylinders per 100 yd3, then 1 set of 3 cylinders per 300 yd3 Agency will break 1 set of 3 cylinders at 28 days. Agency will cast up to 3 control cylinders, any additional control cylinders are the responsibility of the Contractor. Cellular Concrete: 1 set of 4 cylinders (28 days) per day, fill in 2 equal lifts, do not rod , lightly tap the sides, cover and move to area with no vibration. Do not disturb for 24 hours. 2409 Concrete Cylinder Concrete Pavement Observation of probing or coring at the Engineer's discretion. 24327 Thickness ** Producer: 1 beam (28 day) per day per mix. Make additional control beams as necessary. Control beams shall be made within the last Flexural Strength hour of concrete poured each day. Fabricate beams, deliver beams to curing site, and clean beam boxes. Cylinders may be substituted for beams at the discretion of the Engineer. Producer: 1 per 1000 lineal feet per lane of concrete pavement at locations determined by the Agency. The Contractor supplies all materials necessary to perform the required testing. 2162 Concrete Test Beam Data MIT SCAN T2 Report (1 ) - Review the requirements of 2461.3F Certified Ready -Mix Concrete, 2461.3G Concrete Placement and 5- 694.010 Inspector's Checklist in the Concrete Manual. *Small quantity is 25 yd3 or less per week with no gradation testing or plant monitoring required but remember that Concrete Field Testing is required. **Concrete Pavement: Use Certified Ready -Mix Concrete testing rates when: a) The entire concrete paving project is less than 3,500 cu.yd. b) When a secondary plant is used to provide minor work. Contact the MnDOT District IA Inspector to provide servicing of your Federal Aid Project. Agencies using MnDOT Metro Inspection Services will be sampled at the current MnDOT Schedule of Materials Control rates and will be billed accordingly. The testing rates shown in the SMC - LGA are minimums. Take as many tests as necessary to ensure quality concrete. It is recommended that the Agency Plant Monitor be present during critical pours, such as superstructure or paving concrete. If any field test fails, reject the concrete or if the Producer makes adjustments to the load to meet requirements, record the adjustments on the Certificate of Compliance and Weekly Concrete Report. Retest the load and record the adjusted test results. Make sure the next load is tested, before it gets into the work. If batching adjustments are made at the plant, test the adjusted load, before it gets into the work. Continue to test the concrete when test results are inconsistent or marginal. Material not meeting requirements shall not knowingly be placed in the work. If failing concrete inadvertently gets placed in the work, use either the MN/DOT Standard Specifications for Construction or the Schedule of Price Reductions for Concrete to address penalties. It is recommended that the Agency representative continually monitor the progress of all concrete pours. (It is not a recommended practice to only perform minimum testing requirements and leave the project.) 2017