Impact of Pavement Stiffness on Performance of Traffic Speed Deflection Measurements

Abstract

Traffic speed deflection devices (TSDDs) have attracted much attention as innovative tools for assessing the structural capacity of highway networks. However, the sensor and operational limitations of these devices in assessing accurately and precisely the pavement structural condition have not been thoroughly established. In this study, the performance of the traffic speed deflectometer (TSD) measurements was evaluated using data from six instrumented pavement sections. The tested sections included different pavement types such as flexible, composite, and rigid pavements with varying overall level of stiffness. Based on the comparison between TSD measurements and the data obtained from field-installed instrumentation, TSD could measure the deflection velocity profiles reliably at flexible pavement sections. The level of noise superimposed on the signal of TSD deflection velocities was highly dependent on the pavement type and stiffness.