Calibration of the MEPDG Resilient Modulus Prediction Model for Subgrade Soils in Shanxi, China

Subgrade soils are very important materials for supporting highways. Current AASHTO pavement design procedures recommend the resilient modulus (Mr) of subgrade soils for pavement design and analysis. It is well known that resilient modulus of subgrade soils is not only dependent to in-situ state of stresses, moisture contents and compaction ratio, but it is also site-specific. The primary objective of this study is to calibrate the resilient modulus (Mr) model of Shanxi, China subgrade soils recommended by Mechanistic-Empirical Pavement Design Guide (MEPDG) using repeated load triaxial (RTL) testing data. A total of 135 resilient modulus data were obtained using the GDS dynamic triaxial testing system. Calibration results show that parameters k1, k2, and k3 in MEPDG resilient modulus model are .642, .212, and -.906, respectively.