Ricerc@Sapienza

There is general evidence that the good performance of geosynthetic-reinforced earth retaining walls (GRWs) observed after strong seismic events can be attributed to their capacity to redistribute seismic-induced deformations within the reinforced zone, provided that the reinforcements are characterised by adequate extensional ductility. Therefore, it is desirable to promote the acti-vation of internal (or local) plastic mechanisms, involving the reinforcement strength, since the design phase. In this study, the seismic performance of two earth retaining walls is compared.

Safety of a foundation under seismic loading is strongly dependent on the inertial forces transmitted by the superstructure, exchanged with the surrounding soil and acting into the foundation itself. The latter contribution, typically neglected for shallow and pile foundations, should be considered for caisson foundations, much more massive and rigid than the foundation soil.

Seismic performance of slopes can be assessed through displacement-based procedures where earthquake-induced displacements are usually computed following Newmark-type calculations. These can be adopted to perform a parametric integration of earthquake records to evaluate permanent displacements for different slope characteristics and seismic input properties.

This paper describes a new procedure for the performance-based design of geosynthetic-reinforced earth-retaining walls (GREs) using the pseudo-static approach. In this procedure, the seismic coefficient k is calibrated against given levels of seismic performance, the latter typically expressed in terms of threshold values of the permanent displacements accumulated during the seismic event. An equivalence between the seismic-induced upper-bound displacements and the seismic coefficient k is obtained applying the Newmark’s