Evaluation of Technologies for Nondestructively Determining Concrete Pavement Thickness

The U.S. Army Engineer Research and Development Center (ERDC) was tasked by the U.S. Air Force (USAF) to evaluate the capability of emerging nondestructive testing equipment to accurately estimate the thickness of pavement surfaces without requiring large footprint equipment or pavement repairs. The ERDC research team conducted an evaluation of eleven nondestructive technologies, including eight ground penetrating radar devices and three different seismic technologies, on nineteen concrete test locations with varying pavement thicknesses. For each of the different pavement types, a single core was extracted to provide calibration points. The involved vendors and researchers estimated initial thickness, and upon receiving the calibration core thicknesses, final thickness estimates were computed. The accuracy of each technology was quantified by calculating the absolute difference between the actual core measurement and the estimated measurement. This paper describes the eleven different technologies, their performance on the test locations, and comparisons in terms of accuracy and implementation difficulty.