Centrifuge Modelling of Flexible Retaining Walls in Saturated Sand under Seismic Actions.

In this work the seismic behaviour of flexible retaining walls embedded in saturated sand has been inevstigate carring out a total of seven centrifuge tests at the Schofield Centre of University of Cambridge. The head of piezometric fluid has been collocated at the excavated level. Two possible structural configurations have been chosen: cantilever walls and walls with one level of props at the top. The results have been examined in detail in terms of the monitored physical quantities: acceleration in the soil, walls displacements, pore pressures, bending moment and axial force in the props when present. Focus is made on amplification phenomena, phase difference in the accelerations, developing of pore pressures and related decrease of soil shearing resistance, collapse mechanism of the walls, entity of accumulated displacements and changing in bending moment distribution. A further level of interpretation has been represented by the comparison of the results with respect tests performed on similar models in dry sand and the prevision of bending moment with Limit Equilibrium Analyses. In the last Chapter the calibration of an advanced constitutive model is carried out.