BACKGROUND: Traffic Speed Deflection Devices (TSDDs) that measure surface deflection at traffic speeds are used by several highway agencies in the United States and other countries to provide data to help with management of the highway network. For example, these data can be used for assessment of pavement structural condition, selection of pavement treatments, and other purposes. In comparison with traditional pavement deflection measurement (e.g., falling weight deflectometers), TSDDs provide a means for acquiring extensive amounts of data in a short period of time. However, the data obtained from TSDD measurements are influenced by many factors such as pavement type, pavement structure, climatic conditions, and speed of operation. Recognizing that no widely accepted practices for verifying the measurements obtained by TSDDs is currently available, research is needed to identify the deflection measurements that are required for pavement structural assessment and other applications and develop a procedure for verifying TSDD measurements and also to develop a recommended standard practice for implementing this procedure.

OBJECTIVE: The objective of this research was to develop a recommended standard practice for verification of the measurements obtained by TSDDs on highway pavements for consideration and adoption by AASHTO.

Status: Research is complete; contractor's final report is available at

https://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP_Project_10-105_Final_Report.pdf