Soil response under vertical accelerations: 1-g shaking table results

Abstract

Recent seismic events have renewed interest in assessing near-fault ground motions, where the role of vertical ground acceleration was revealed to be significant. Geotechnical studies on near-fault effects are still lacking; specifically, although numerical studies have been performed, experimental tests on large-scale models are not yet available in the literature. This paper presents the outcomes of an experimental project to improve our understanding of the vertical earthquake component for near-source conditions and its propagation on the uppermost soil layers. Specifically, the experimental campaign aims to identify the dynamic response of an ideal soil column to vertical accelerations. Particular attention is devoted to the amplification amount of the vertical input motion. The research results confirm the importance of the near-fault effects and provide valuable tools for studying the soil response under vertical actions.