Evaluation of Rutting Variations in FHWA Full-Scale Accelerated Pavement Testing

Abstract

The Federal Highway Administration (FHWA) has been conducting full-scale pavement tests using two Accelerated Loading Facility (ALF) machines for over 18 years. Due to the expense of full-scale pavement testing, most pavements were tested without replication. Variation in performance in replicate tests becomes a major concern when aging takes place in the asphalt pavements. In order to increase our confidence in full-scale testing results, replicate tests were conducted during rutting experiments in a recently completed Superpave validation study (1993-2001). This paper summarizes the results of replicate tests, which were conducted on 12 pavement test sites. Statistical tests were first performed on the rutting results in the replicate pavements. Asphalt aging effect on the rutting was discussed. The variation components were identified and accuracy curves were developed for all test pavements. Finally, the rutting variations among the different pavement layers were also evaluated.