Acceleration amplified and de-amplified responses within geosynthetic-reinforced soil structures

Physical data from various dynamic centrifuge modeling and shaking table tests on geosynthetic-reinforced soil (GRS) structures are compiled and used to evaluate the acceleration amplified and de-amplified responses within GRS structures. Analysis results show the horizontal acceleration (a_h) inside GRS structures has a nonuniform distribution with height and varies with maximum input acceleration (a_max). The variation and magnitude of acceleration amplification factor (A_m), the ratio of a_h to a_max, decrease with the increasing a_max. The horizontal acceleration inside GRS structures amplifies mostly at approximately a_max<0.40g and attenuates at a_max≥0.40g. The results also show the acceleration amplified and de-amplified responses are highly dependent on acceleration frequency f. The acceleration inside GRS structures amplifies considerably when the predominant and fundamental frequencies are close. Further, this paper examines the A_m and a_max relationships (i.e., A_m=1.45-a_max/g), proposed based on a series of finite element simulations and adopted in the current GRS structure design guidelines. The comparative results indicate A_m and a_max relationships adopted in the current design guidelines follow the lower bound of the physical data compiled in this paper, specifically for underestimate of A_m at lowera_max. The results obtained from this study provide insightful information for seismic design of GRS structures.