Development of the Florida Department of Transportation’s Percent Within Limits Hot-Mix Asphalt Specification (05-1510)
Gregory Allen Sholar, Florida Department of Transportation
Gale C. Page, Florida Department of Transportation
James A. Musselman, Florida Department of Transportation
Patrick B Upshaw, Florida Department of Transportation
Howard L. Moseley, Florida Department of Transportation

The Florida Department of Transportation, herein referred to as the Department, adopted a percent within limits approach in July 2002 for the acceptance and payment of all hot-mix asphalt. Contractor’s test data, after being verified by the Department, is used to calculate payment. Acceptance and payment for dense-graded Superpave mixtures is based on the following five asphalt material properties: 1) roadway density, 2) percent air voids, 3) asphalt binder content, 4) percent passing the No. 8 sieve, and 5) percent passing the No. 200 sieve. Acceptance and payment for open-graded friction course mixtures is based on the following four asphalt material properties: 1) asphalt binder content, 2) percent passing the 3/8 inch sieve, 3) percent passing the No. 4 sieve, and 4) percent passing the No. 8 sieve. Contractor’s test data from recently completed construction projects was used to develop representative standard deviations of the asphalt material properties used for payment and acceptance. These standard deviations were then used to develop tolerance values used in the percent within limits system. A system has been developed to handle acceptance and payment of small quantity LOTs (two or less sublots) within the same specification. In lieu of the Department sampling and testing numerous independent samples and performing F and t-tests to validate the Contractor’s results, an alternative verification and resolution system has been developed.