Professor, Tennessee Technological University, Cookeville, TN
Graduate Ph.D. Candidate, Tennessee Technological University, Cookeville, TN
Transportation Manager I, Nashville, TN
Professor Emeritus, Tennessee Technological University, Knoxville, TN
Pages: 15 Published: Jan 2001
In 1992, the Tennessee Department of Transportation (TDOT) initiated a project to pair aggregate performance with pavement functional needs so that all Tennessee aggregate sources could be used efficiently. The principal result of the project was a new pre-evaluation procedure for aggregate polish resistance called the Tennessee Terminal Textural Condition Method (T3CM). The T3CM uses an up-scaled version of the AASHTO T 304 device to monitor an aggregate's ability to retain angularity and texture through a simulated aging process.
In the fourth phase of the study, twenty-three coarse aggregates, sampled at the cold feed stockpile, are subjected to T3CM, T3CM with sand aging, X-ray diffraction, British Pendulum, Loss-on-Ignition, and chemical percent silica techniques. By comparing skid performance versus traffic (ADT, passes, and ESALs) with laboratory test results, aggregate performance and aggregate source variability may be categorized for effective use. Preliminary results indicate that the correlation between T3CM and skid performance (R2 = 0.74) is far superior to the correlations between ASTM C 25 percent silica (R = 0.38), percent silica by X-ray diffraction (R2 = 0.36), and BPN 9 (R2 = 0.0004) with skid performance.
polish resistance, coarse aggregate, skid resistance, void content, microtexture, particle shape, percent silica, x-ray diffraction
Paper ID: STP10808S