2007 KYTC/KAHC2007 KYTC/KAHC

Information Exchange MeetingInformation Exchange Meeting

““Asphalt Materials”Asphalt Materials”

Allen H. MyersAllen H. Myers

Division of Materials, Asphalt BranchDivision of Materials, Asphalt Branch

March 16, 2007March 16, 2007

Kentucky CultureKentucky CultureWhich festival occurs annually in West Liberty?

Sorghum

Festival

Kentucky HistoryKentucky HistoryWhat is Kentucky’s oldest city?

Harrodsburg

What’s on the agenda for today?What’s on the agenda for today?

HMA selection warrants

Department’s HMA verification responsibilities

HMA Selection WarrantsHMA Selection Warrants• Changes for 2007

– Eliminate all 0.50-in. nominal-maximum surfaces

– Specify only 0.38-in. nominal-maximum surfaces

– Reduce lift thickness of Compaction Option A surface mixtures

– Revise minimum threshold for PG 76-22 from 3.0 million to 7.0 million ESALs

HMA Selection WarrantsHMA Selection Warrants• Revise all 0.50-in.

nominal-maximum surfaces to 0.38-in. size

• Combat permeability

• Sacrifice rut resistance?

• Research continues to reduce permeability of 0.50-in. surfaces

• Reduce number of bid items

Kentucky GeographyKentucky GeographyWhere is Pound Gap?

Near Jenkins, in Letcher County

Kentucky SportsKentucky SportsIn which city did the University of Kentucky

win the 1978 NCAA basketball title?

St. Louis,

Missouri

Department’s HMA VerificationDepartment’s HMA Verification• Subsection 402.03.03,

Department’s verification of contractor’s HMA acceptance test results, does not satisfy FHWA’s 23 CFR 637 requirement– Department’s verification

samples are not independent– Department does not perform

statistical comparison of contractor and Department data

Department’s HMA VerificationDepartment’s HMA Verification• Emphasize importance and usage of control charts

– Plot and evaluate all critical HMA properties– Plot both contractor’s acceptance and Department’s

verification test results– Analyze charts for trends

• Department results consistently above or below contractor’s results

• Contractor’s results different for sublots that Department verifies as compared to sublots that Department does not verify

0

5

10

15

20

25

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Test Number

Perc

en

t P

assin

g

Contractor's Data

Department's Data

Upper Limit

Low er Limit

Department’s HMA VerificationDepartment’s HMA Verification• Apply tolerances

comparing one Department test to average of three contractor tests for sublots not verified by Department

• Resolve any discrepancies according to Section 113

Department’s HMA VerificationDepartment’s HMA Verification

sp2 = [sc

2(nc-1)+sa2(na-1)]/(nc+na-

2)

t = (Xc-Xa)/[(sp2/nc

• “F and t” test comparison– For projects involving six

or more lots of any one bid item

– Compare one Department test to three contractor tests for sublots not verified by Department

Allen H. Myers

Division of Materials, Asphalt Branch

Phone: 502-564-3160

Fax: 502-564-7034 E-Mail: Allen.Myers@ky.gov

Thank You!Thank You!

2007 KYTC/KAHC2007 KYTC/KAHC

Information Exchange MeetingInformation Exchange Meeting

Kentucky HistoryKentucky HistoryAfter the Battle of Point Pleasant in 1774, which

group of Native Americans relinquished all claims to the new settlers of Kentucky?

The Shawnee