Examining dynamic soil pressures and the effectiveness of different pile structures inside reinforced slopes using shaking table tests

To study the distribution and variation of dynamic soil pressures in reinforced soil slopes and the effectiveness of different stabilizing structure types, we conducted a series of shaking table tests on soil slopes reinforced by two types of stabilizing structures: constrained anti-slide pile (beam-pile) and pre-stressed anchor slab-pile walls (anchor-pile), under different shaking intensities. Through examining the recorded dynamic responses (the soil pressures and accelerations measured at different locations in model slopes) and the observed post-test behaviors in the slope models, we analyzed the distributions of response dynamic soil pressures, accelerations, spectral displacements (S-d) and the displacements and inclinations for two stabilizing structure models under different shaking intensities. We found that the frequency contents of the dynamic soil pressures change with a shift in the predominant frequency in the spectrum under high shaking intensity, and the changes in the dynamic soil pressure mainly occur on those components in some relatively low frequency bands, and we infer that these changes may mainly result from the change in the response acceleration within the reinforced slope. Finally, through comparing the spectral displacements in slopes, the measured displacements and the inclinations of pile blocks under different shaking intensities, we found that anchor piles can better support the slope than beam piles, under similar shaking conditions. These results help us better understand the features of the dynamic soil pressures and also provide evidence to select stabilizing structures for reinforcing the slope against earthquakes.