1-g shaking table investigation on seismic performance of polymeric-strip reinforced-soil retaining walls built on rock slopes with limited reinforced zone

Abstract

In the current study, the methodology for construction of reinforced soil in mountainous terrain, where there is a geometry limitation for the reinforced zone, is evaluated. Shaking table tests were carried out on physical models with 0.8m-high polymeric-strip reinforced-soil walls (PSWs) on rock slope subjected to variable-amplitude harmonic excitations. The influence of the presence of backfill between reinforced mass and rock slope, strips length, base acceleration, and loading duration are investigated. The results of failure mechanisms, the horizontal displacements of models, and the acceleration amplification factor are analyzed. Results indicate that the deformation mode of walls largely depends on the reinforcements’ length and backfill so far as two different kinds of failure patterns were formed, namely single-block failure for models with stepped-shaped rock base with no backfill, and two-wedged failure mechanism for models with slope-shaped rock base with backfill at the end of reinforced mass. The observed predominant mode of wall deformation was a combination of bulging of the facing and rotation about the wall base without base sliding. In tested PSW models, the threshold acceleration related to the onset of plastic displacements of models was (0.7–0.8) g, and the threshold acceleration related to the onset of the development of active wedge failure was (0.75->1) g, both of which depend on the backfill and strips length. This yielding acceleration decreased with the presence of backfill and decreasing the length of strips.