A Mechanistic-Empirical Subgrade Design Model Based on Heavy Vehicle Simulator Test Results

Although Accelerated Pavement Testing (APT) is often done with specific objectives, valuable pavement performance data is generated over the long-term that may be used to investigate pavement behaviour in general and calibrate mechanisticempirical design models. This paper presents a study on subgrade permanent deformation based on the data generated from a series of Heavy Vehicle Simulator (HVS) tests done at the Richmond Field Station in California. The total subgrade deflection was found to be a better indicator of subgrade permanent deformation than the commonly accepted subgrade vertical strain. A mechanistic-empirical subgrade deformation model was also calibrated successfully for a range of subgrade permanent deformation levels from 1 to 21 mm. The subgrade permanent deformation was found to increase rapidly at subgrade deflection levels above 800