Mechanistic-empirical analysis of geogrid-stabilized layered systems: Part II. Analysis

Abstract

In recent years, the mechanistic-empirical design method has become popular for pavement design. In the mechanistic-empirical design of geogrid-stabilized roads, elastic solutions for the geogrid-stabilized layered system are necessary but not yet available. In the companion paper, the analytical solutions for the geogrid-stabilized layered system were derived according to the layered elastic theory and the mechanistic-empirical approach. In this study, the elastic responses (i.e. vertical stresses, radial stresses, and elastic strains) due to the effect of the geogrid were investigated based on these solutions. The analytical solutions were then employed to estimate the reduction of vertical stresses underneath the geogrid compared with the measured results, which show reasonable agreement. A parametric study was conducted to investigate the effect of lateral restraint and tensioned membrane on the elastic responses, with the surface deformation at different base thicknesses and base-to-subgrade modulus ratios. The results clearly show that the lateral restraint effect is more significant compared to the tensioned membrane effect when the surface displacement is less than 75 mm, especially in a section with a relatively thick base course. The analytical solutions may be implemented in the mechanistic-empirical design of geogrid-stabilized unpaved roads.