SERA TA Project # 35

Title of Project:
SHAking Table testing for Near Fault Effect Evaluation (SHATTENFEE)
Hosting Research Infrastructure:
University of Bristol

No. of Users:
17

Team Leader:
Università del Sannio
Armando Lucio Simonelli

Team:
Università del Sannio
Luigi Di Sarno
Augusto Penna
Maria Incoronata Fredella
Liberatore Arienzo
Diletta Aliperti
Carmine Lucadamo

University of Athens
Michalis Fragiadakis
Ioannis Taflampas
Spyridon Diamantopoulos

University of Trento
Alessandro Gajo
Farzaneh Ghalamzan Esfahani
Piotr Kowalczyk
Mattia Dall’Acqua

NGI (Norwegian Geotechnical Institute)
Amir M. Kaynia

Universidade de Lisboa
Jorge de Novais Bastos

University of the West of England-UWE Bristol
George Anoyatis


Summary of Project:

Recent surveys conducted after destructive earthquakes demonstrated that, in near fault (NF) conditions, combined vertical and horizontal motions caused unusual and poorly understood damage to geotechnical and structural systems. In NF conditions, ground motions are influenced by the short distance from the fault, short time delay between P- and S-wave arrivals, and the seismic waves’ incidence direction (generally not vertical). However, there is limited understanding of the effects of such NF motions on soil and superstructure response. Consequently, the existing codes of practice do not account for the combined effects of horizontal and vertical components in NF conditions and need urgent updating.
Furthermore, little is understood about vertical motion effects on SSI systems, so this project will focus on this aspect as a key step in understanding the overall problem. The vertical dynamic behaviour of a typical soil deposit, with and without the presence of a foundation system and a simplified scaled oscillator as a representation of a building superstructure, will be explored experimentally on the 6-DoF shaking table at Bristol University, using a new soil container specifically designed for vertical wave propagation.
The vertical dynamic response characteristics, e.g. the period of vertical vibration, damping coefficient, and effect of soil non-linearity and excitation characteristics (e.g., harmonic, impulse, seismic), will be investigated experimentally and numerically to provide fundamental insight and guide further research and code of practice development. If it proves feasible, additional insights will be gained from pilot experiments using combined horizontal and vertical motions using Bristol’s existing laminar shear stacks, which were not designed for vertical motion inputs.