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Earthwork. LOTs. 120-8.1 Embankment Construction – LOTs What is the maximum length of a LOT? Mainline pavement lanes, turn lanes, ramps, parking lots, concrete box culverts and retaining wall systems A LOT is defined as a single lift of finished embankment not to exceed 500 feet.
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LOTs • 120-8.1 Embankment Construction – LOTs • What is the maximum length of a LOT? • Mainline pavement lanes, turn lanes, ramps, parking lots, concrete box culverts and retaining wall systems • A LOT is defined as a single lift of finished embankment not to exceed 500 feet. • Shoulder-Only areas, bike/shared use paths, and sidewalk areas • A LOT is defined as 2000 feet or one Day’s Production, whichever is greater.
Independent Verification • Question from Industry – How is Independent Verification processed. • Section 120-10 Independent Verification • 120-10.1.5 - In addition to the Verification testing, the Engineer may perform additional Independent Verification (IV) testing. The Engineer will evaluate and act upon the IV test results in the same manner as Verification test results.
Independent Verification • QC Sample - 108 pcf • VT Proctor - 112 pcf • IV Proctor – 116 pcf • Resolution Proctor 116 pcf • What proctor should we use? • Should they resample the material?
Reclaimed Asphalt Pavement (RAP) – 120-8.4 • Where is RAP prohibited? • Construction areas that are below the seasonal high groundwater table elevation. • The top 12 inches of embankment. • MSE Wall backfill. • Minimize RAP content to avoid possible long term settlement
Reclaimed Asphalt Pavement (RAP) • Specifications • Soil & RAP mixture120-8.4.2 • Prohibited in Retaining Wall Systems • Alternate Layer Construction 120-8.4.3 • Shoulder Base 283 • Stabilizing Material 914
Max. Lift Thickness • Test Strip Requirements for 12 inch thick compacted lifts. • 125-8.1.6 – In the soil envelope - maximum allowed thickness of backfill is 6 inches.
Soil Envelope (No Thick Lift) Soil Envelope 125-8.3 Top Zone - Up to the base or final grade 1 foot above pipe PIPE Cover Zone Bedding Zone 4” below the pipe Lowest Zone Bottom of Trench
Reduced Frequency Testing • How many passing density tests are required before the contract allows Reduced Frequency Density Testing for; • Pipe backfill • Embankment
Embankment -Reduced Frequency • 120-10.1.6 • Reduced Frequency Testing is allowed after 12 passing tests with no Resolution tests in favor of Verification. • Required to use similar compaction effort on the untested LOT • Select test location randomly from one of the two LOTs under consideration. • Requires Engineer’s permission to place material over untested LOT • Not allowed in shoulder only areas, sidewalks bike/shared use paths. (LOT size)
Pipe Backfill – 125-9.1.1 • Reduced Frequency Testing is allowed after 6 passing tests with no Resolution tests in favor of Verification. • Required to use similar compaction effort on the untested LOT • Select test location randomly from one of the two LOTs under consideration. • Requires Engineer’s permission to place material over untested LOT
125 – Pipe Backfill • Plastic and Metal pipe backfill requires 95% of Standard Proctor for density. • Concrete pipe backfill requires 100% of Standard Proctor. • Structure backfill requires 100% of Standard proctor regardless of the type of pipe joining the structures.
Metal Pipe / Structure Density Acceptance • Metal pipe requires 95% maximum density • Structure requires 100% maximum density • The pipe and structure require separate density tests because of different density requirements. • This will be clarified in the July 2013 specifications
Stabilization Materials- Sampling • Commercial Material - Approved Source (usually Aggregate Base) 160-2.1 • Requires a Cert from the Mine • No field sampling or testing required • Existing Base 160-2.3 • No testing requirements • IV testing is encouraged and should be performed on any material if there are concerns i.e. bad clay or organic materials … • Local Materials 160-2.2 • Acceptance requires: • Source investigation (440 /440A– Projects let after 3/1/11 ) • Sample & test from the roadway for material acceptance 160-3.2.1 (440/440B - Projects let after 3/1/11)
Stabilization - Local Materials • Meet the requirements of Section 914- 160-2.2 (440/440A) • Local material may be clay from on-site, material from another construction project, or possibly byproducts from a process. • The Specifications require testing of the material before it is brought to the roadway and spread. • Sampling • Section 914 requires a minimum of 3 organic content test results and one LL/PI test result per source. • The Engineer should partner with the contractor to investigate the source or stockpile and evaluate each material. (best practice) • Use one sample card for each source or stratum of material • Provide a minimum of 3 - ½ bags of material for each source
C22 card • “Material ID” - Enter 440 for projects let prior to March 1, 2011 and 440A if the project is let after March 1, 2011 (This will show in the project job guide schedule) • “Remarks” - Enter “Source testing “ • “Sample Number – Enter “C001”, “C002”, “C003”, etc and either “Q” or “V”
Roadway Acceptance– Local Material • Sampling and Testing of Local Materials - Section 160-3.2.1 (440/440B) • Requires Sampling after spreading and before mixing • QC 1 per 2 LOTs – VT 1 per 8 LOTs • “Sample Numbering” - “C001”, “C002”, “C003”, etc and “Q” or “V” • Collect three pint size bags of material across the roadway (FM 1 – T267) • Engineer Verification, Resolution and Acceptance - 160-3.2.1.1 • Stabilizing materials require acceptance before the material is mixed into the Subgrade
C-22 CARD Example • “Material ID” - Enter 440 for projects let prior to March 1, 2011 and 440B if the project is let after March 1, 2011 (This will show in the project job guide schedule) • “Sample Number”– Enter “C001”, “C002”, “C003”, etc and either “Q” or “V” • “Plant or Pit No.” Enter “ROADWAY“ • “QUANT REP” Enter “LOTS 1 thru 8” • “Remarks” Enter “LL/PI and ORGANIC TEST”
RAP or RAP Blend Stabilizing Material • Source Investigation (440/440A) • Evaluate the stockpile as a local material - 160-2.2 • If failing organic content is due to the asphalt content of RAP or RAP Blended material the department may modify acceptance (after careful evaluation) • Modified Acceptance for RAP or RAP Blend (440/440B) http://www.dot.state.fl.us/statematerialsoffice/administration/resources/library/materialsbulletins/topics/2011/mb02-11.pdf • Sample for LL/PI before mixing • Sample and test for Asphalt Content (FM 5-563) (NCAT) after Mixing • The upper limit for FM 5-563 in the mixed Subgrade is 4.7% • Failure may indicate too much Asphalt or the presence of a material with a high organic content
Sampling for “RAP” Stabilizer Material • Sample after spreading and before mixing according to 160-3.2.1 (440/440B) • Sample Transmittal Card Example: • “Remarks” • “RAP Premixing no organic test” • “ LL/PI test only” • Sample size is ½ bag
Sample for Asphalt Content • Sample the material after mixing in 160-3.3 (440/440B) • Sample size is 1 bag • Sample Transmittal Card Example • Use the same sample number as used for LL/PI testing • “remarks” • “RAP - Substitute FM 5-563 for FM1-T267”
Independent Verification • 120-10.4.1 Standard Proctor Maximum Density Determination: The Engineer will verify the Quality Control results if the results compare within 4.5 lb/ft3 of the Independent VerificationVerification test result. Otherwise, the Engineer will take one additional sample of material from the soil type in question. The State Materials Office or an AASHTO accredited laboratory designated by the State Materials Office will perform Resolution testing. The material will be sampled and tested in accordance with AASHTO T-99, Method C. The Engineer will compare the Resolution Test results with the Quality Control test results. If all Resolution Test results are within 4.5 lb/ft3 of the corresponding Quality Control test results, the Engineer will use the Quality Control test results for material acceptance purposes for each LOT with that soil type. If the Resolution Test result is not within 4.5 lb/ft3 of the Contractor’s Quality Control test, the Independent VerificationVerification Test result will be used for material acceptance purposes. A1