Mechanistic-empirical performance prediction of geogrid-modified soft soil subgrade

Over the decades, geogrids have been increasingly used in flexible pavements primarily for base reinforcement and subgrade improvement. Yet most of the existing methods for designing a geogrid-modified pavement are largely empirically based and limited to the type of geogrid products and certain conditions. With the recent release of the new pavement design program by AASHTO, DARWin-ME, the mechanistic-empirical (ME) approach is becoming a routine practice for pavement analysis and design. Recognizing that the ME concept provides a more rational and realistic methodology than a purely empirical approach, the study presented in this paper is aimed to characterize the permanent deformation of geogrid-modified soft soil subgrade by using the ME approach. Based on both experimental measurements and results of numerical modeling, ME models were adapted and customized to predict permanent deformation of geogrid-modified soft soil subgrade.