Performance of Various Geosynthetic-Reinforced Embankment and Foundation Systems Subjected to Reverse Fault Movement

Abstract

This paper presents reduced model tests on geosynthetic-reinforced soil (GRS) embankment and foundation systems subjected to reverse fault movements. Three types of reinforced foundations—soil foundations reinforced with planar geotextiles, geosynthetic encased granular columns (GECs), and geocells—were examined to investigate the effectiveness and reinforcing mechanisms in mitigating reverse fault-induced ground deformation. Digital image analysis (DIA) techniques were adopted to evaluate the surface displacement profiles, maximum angular distortion (βmax), and shear strain contours at different magnitudes of reverse fault displacement. The maximum horizontal facing displacement (Δmax) of the overlying GRS embankment was also determined to evaluate the overall performance of the GRS embankment and foundation systems. Test results indicated that different reinforcing mechanisms and the development of fault-induced shear ruptures were observed for three types of reinforced foundations. The geocell foundation had the most optimal effects in minimizing the βmax at the ground surface, as well as the Δmax of the GRS embankment. Compared with the unreinforced foundation, a reduction of 39.1% in the Δmax value of the GRS embankment was observed at a fault movement to foundation thickness ratio (S/HF) of 37.5%. For all the reinforced embankment and foundation systems, the overlying GRS embankment remained stable, and only localized deformation on the wrapped-around facing was observed. The influence of overburden pressure applied by the GRS embankment on the performance of each reinforced foundation, as well as the design implications of the embankment and foundation systems, were discussed in the present study.