LAUSR

Structural adequacy, which is an important aspect of pavement management activities, is typically evaluated using surface pavement deflections measured by the falling weight deflectometer (FWD). Technology that can collect continuous deflection data at traffic speeds can potentially supplant single-point location deflection measurements provided by the FWD for network-level pavement management system (PMS) applications. Previous studies have evaluated the traffic speed deflection devices (TSDD) performance by comparing their results with the FWD measurements. Although appropriate correlations and indices to compensate for the differences in load have been made, a direct comparison under the same loading conditions has not been reported in the literature. The purpose of this paper was to present the results of a field study to evaluate TSDDs by comparing their pavement deflection parameters with those from embedded sensors under actual loads. Two TSDDs were used in this study: the Greenwood traffic speed deflectometer (TSD), and the Applied Research Associates, Inc. (ARA) rolling wheel deflectometer (RWD). The lessons learned from the study are emphasized for further consideration toward developing a calibration methodology for value-added future analyses.