1 Overview CQC Asphalt Specifications

 Payment based on Contractor’s Quality Control tests.  FDOT runs verification tests at a lesser frequency.  Payment is based on roadway density, air voids, asphalt content and gradation.  Uses Percent Within Limits (PWL) statistical specs.  Separate Master Production Range to catch outliers.  Began with July 2002 workbook. 2

 Standard Lot size:  4,000 tons for dense mix or 2000 tons for OGFC.  Four sublots per Lot.  Plant Lot & Roadway Lot same.  Engineer establishes sampling points.  Random basis.  Use Excel spreadsheet.  Directs Contractor when to sample.  Contractor does all the sampling. 3

 QC = Quality Control = Contractor  VT = Verification Test = FDOT Project personnel (typically a consultant)  IV = Independent Verification = FDOT District Materials personnel  RT = Resolution Testing = FDOT District Materials personnel 4

Typical 1,000 ton Sublot - composed of 50 truckloads (20 tons each) 5

Lot 1, sublot 1 50 trucks, 20 tons each = 1,000 ton sublot Random Sample Numbers by Sublot 6

Sublot 1Sublot 2Sublot 3Sublot 4 LOT = 4,000 Tons QC randomly tests one per sublot. VT randomly tests one split per Lot. RT splits held until Lot is verified. QC Testing at Pla QC Testing at Plant Tons 7

Sample Splits G mb G mm Ext/Grd QC VT RT 8

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10 Table Master Production Range CharacteristicTolerance (1) Asphalt Binder Content (%)Target ± 0.55 Passing No. 200 Sieve (%)Target ± 1.50 Air Voids (%) Coarse Graded2.00 – 6.00 Air Voids (%) Fine Graded2.30 – 6.00 Density, %Gmm (2) Coarse Graded (minimum)93.00 Fine Graded (minimum)90.00 (1) Tolerances for sample size of n = 1 from the verified mix design (2) Based on an average of 5 randomly located cores

 Terminate Lot if:  One sublot failure for Air Voids.  One sublot density failure.  Two consecutive sublot density failures for fine mix.  Two consecutive sublot failures for gradation.  Two consecutive sublot failures for asphalt content.  2 individual core densities for coarse mix less than 91.00% Gmm. 11

 At completion of each Lot  Test VT sample for randomly selected sublot  Split from QC sample  Use test method precision for comparison  Excel spreadsheet  If everything compares favorably…  Calculate pay based on QC results  If not….go to Resolution testing  District Materials Office 12

Sublot 1Sublot 2Sublot 3Sublot 4 LOT = 4,000 Tons QC tests one per sublot. VT randomly tests one split per Lot. VT Testing 13

Between-Laboratory Precision Values Table Table Between-Laboratory Precision Values PropertyMaximum Difference G mm G mb (gyratory compacted samples) Gmb (roadway cores – fine graded mixture) Gmb (roadway cores – coarse graded mixture) PbPb 0.44 percent P -200 FM 1-T 030 (Figure 2) P -8 FM 1-T 030 (Figure 2)

 If the verification testing does not compare on a pay property  Resolution samples tested by third party lab for the property in question  All sublots are tested  Use test method precision for comparison to QC  Excel spreadsheet  If everything compares favorably…  Calculate pay based on QC results  If the sample does not compare  Resolution results are used to calculate pay for that property 15

Sublot 1Sublot 2Sublot 3Sublot 4 LOT = 4,000 Tons QC randomly tests one per sublot. VT randomly tests one split per Lot. RT tests non-comparison property for each sublot. RT Testing Tons 16

 Roadway and Plant Lot the same.  6-inch diameter cores.  Five cores per sublot.  Randomly located (stratified manner).  Use spreadsheet.  Minimum of 3 cores/sublot.  Retain QC cores for VT & RT. 17

 Density testing not required for:  Total quantity of hot mix < 2,000 tons.  Widening or shoulders with a width of 5 ft or less.  FC-5  Misc. Asphalt, Variable thickness or overbuild layers.  Leveling, Bridge Decks, Approach slabs.  First lift of asphalt placed on subgrade.  Bike/shared use paths.  Crossovers or intersections.  Any course thickness < 1 inch or specified spread rate converts to < 1 inch. 18

 Testing not required for the following areas when they are less than 1,000 feet long:  Turning lanes  Acceleration lanes  Deceleration lanes  Shoulders  Parallel parking lanes  Ramps  Use rolling procedure (equipment and pattern) as approved by the Engineer.  Density testing required everywhere else. 19

 If two or less sublots:  Use Small Quantity Pay Table based on average deviations from target.  If three or more sublots:  Use Percent Within Limits (PWL) for the Lot.  Calculate Pay Factor for:  Density, Air Voids, AC Content, P-200, P-8 20

 Pay factor for each characteristic is determined.  Composite Pay factor is based on:  35%Density  25%Air Voids  25%AC Content  10%P-200  5%P-8  Calculations done by spreadsheet. 21

 Individual Pay Factors Below 0.90  First time correct, 2 consecutive – cease.  Composite Pay Factor 0.80 to 0.89  Cease until problem is resolved.  Composite Pay Factor 0.75 to 0.79  Handle per (EAR).  Composite Pay Factor Less than 0.75  Remove and Replace. 22

 Contractor must remove & replace…OR  Engineering Analysis Report…  If approved by Engineer / Paid by contractor.  Independent Lab approved by Engineer.  Remain in place at composite pay factor, or as determined by Engineer.  Can be waived by Engineer.  Delineation testing by Contractor  Only for asphalt content, density, and gradation. 23

 Handled by the District Materials Office.  One sample per 4,000 tons.  Sampled by Contractor with FDOT supervision.  Compare IV results with QC (test precision).  Use Master Production Range Table  IF IV fails MPR, cease production until problem resolved and then evaluate in-place material. 24

 FC 9.5 and FC 12.5  Handled in same manner as 334 HMA.  FC 5 (OGFC)  Same concepts but different material properties: ▪ Asphalt content, Gradation (P-3/8, P-4, P-200) 25

Questions/ Comments? 26