Centrifuge Modelling of Vegetated Slopes under Earthquake Loading

The behavior of vegetation-reinforced slopes during a sequence of successive earthquake motions was investigated using centrifuge model tests at 1:10 scale. The model roots used in this study were fabricated using Acrylonitrile Butadiene Styrene (ABS) plastic using 3D printing (rapid prototyping). It is shown that in this case, the presence of root system significantly decreases permanent settlement at the crest of the slope. The majority of the reduction was observed during the first two motions, which was related to the mobilization of the root-soil interaction as the roots bend in response to the soil kinematic loading. After this, less difference was observed because the root shear strength contribution reached a limiting value. Discontinuity Layout Optimisation (DLO) calculation was then employed to better understand the failure mechanism of rooted slope and it was found that the improvement of slope performance is mainly mobilized by the increase of yield acceleration and decrease of acceleration response spectra (ARS).