Development of a Profile-Based Smoothness Specification for Asphalt Concrete211 Overlays (Revised)

摘要

The Texas Department of Transportation (TxDOT) is implementing smoothness211u001especifications based on profilograph testing as part of its construction quality 211u001econtrol/quality assurance (QC/QA) program. To improve upon the existing test 211u001emethod, TxDOT sponsored a research project with the Texas Transportation 211u001eInstitute (TTI) to develop a smoothness specification for asphalt concrete 211u001eoverlays based on the current generation of profiling equipment which offer 211u001ebetter accuracy and repeatability than the profilograph. To develop this 211u001especification, researchers evaluated the relationship between pavement profile 211u001eand predicted overlay life assuming reflection cracking as the primary failure 211u001emechanism. This relationship is evaluated in two steps. First, the effect of 211u001esurface profile on predicted dynamic loads is determined by vehicle simulation. 211u001eThen, the effect of dynamic load variability on predicted pavement life is 211u001eanalyzed, This work led to the development of a relationship between the 211u001epredicted change in pavement life associated with the placement of the overlay, 211u001edynamic load variability, and the fracture parameter, n, of the asphalt overlay 211u001emixture.