Comparison of resilient modulus values for Florida flexible mechanistic-empirical pavement design

The primary objective of this study is to recommend correction factors (CFs) for determining equivalent laboratory resilient modulus (M-R) values, given the corresponding unbound granular layer moduli from in situ pavement testing to support the flexible pavement design based on mechanistic-empirical pavement design guide (M-EPDG). To evaluate CFs for limerock base, mechanically stabilised subgrade, and embankment materials used on Florida flexible pavements, the authors conducted field and laboratory test programmes along with reviewing available data. The authors compared field modulus determined from backcalculation of falling weight deflectometer (FWD) data and laboratory determined modulus that considers in situ moisture content condition based on soil-water characteristic curve. To the end, a series of charts were established showing correlation between FWD modulus and CF for each material for the purpose of determining equivalent laboratory M-R with the given FWD backcalculated modulus to provide input for M-EPDG-based pavement design.