Seismic responses of vertical-faced wrap-around reinforced soil walls

A series of shaking table tests on geosynthetic-reinforced walls with a height of H = 0.6 m is performed to investigate the seismic performance of prototype walls with H = 6 m. Ground-wall resonance occurs at small values of horizontal peak ground acceleration (HPGA), namely 0.1–0.5g, with an amplification factor of A_m = 1.2–2.2 at the crest of the wall. This factor decreases with increasing HPGA. For walls that attain states of maximum horizontal displacement (D_max)/H > 5%, the failure mechanism consists of a vertical failure surface at a distance from the facing of 0.3H for the upper half of the wall and a Rankine triangular wedge over the lower half of the wall. Mononobe-Okabe theory gives dynamic earth pressure coefficients that agree well with experimental results based on k_h = η·HPGA/g, where k_h and η are the horizontal seismic coefficient and an empirical constant, respectively, with values of η ranging from 1/4 to 1/3. Furthermore, the maximum tensile forces induced by shaking increase as the depth of reinforcement increases, generating a trapezoidal shape rather than the inverted trapezoidal shape proposed in the literature.