Correlation between deflections from the Falling Weight Deflectometer and those from the Light Weight Deflectometer

Abstract

The objective of this paper is to investigate the correlation between deflections from the Falling Weight Deflectometer (FWD) and those from the Light Weight Deflectometer (LWD) performed on the asphalt surface of different flexible pavements. In this study, twenty test sections wereselected along twelve major highways. Each 250-m long section was located near the weight control station. The deflection measurements were taken at every 25 m along the test section. The results showed that the correlation between deflections from the FWD and those from the LWD exhibited a linear. In addition, the FWD deflections (ranging from 35 to 732 microns with an average of 231 microns) were approximately 10 times the LWD deflections (ranging from 2 to 104 microns with an average of 24 microns), while those calculated by the elastic solution were approximately 6 times. Such difference was caused by the difference in their applied stresses.