A Review on Structural Evaluation of Flexible Pavements using Falling Weight Deflectometer

For rehabilitation design processes, the new Mechanistic-Empirical Pavement Design approach relies heavily on the material stiffness, back calculated from the deflection measurements taken from existing pavements. These measurements are typically made using Falling Weight Deflectometer (FWD) or Heavy Weight Deflectometer (HWD) units. In order to provide high quality and consistent material stiffness data for the Mechanistic-Empirical Pavement Design the deflection results obtained at radial distance in between 0 and 1800 mm through geophone in FWD is highly useful. This review sought to examine the state-of-practice in FWD testing, analysis procedures and its research findings at national and international scenario. The deflection value obtained from FWD load application is directly used to estimate the structural and function condition of pavement is highlighted. Back calculation methods, correction to seasonal variations and calibration of FWD are not reviewed.