Back-calculating vibro-installation stresses in stone-column-reinforced soils

An investigation was carried out to study the effect of the vibro-installation of stone columns on the soil state of stress. Post-installation soil parameters and load-settlement records were utilised to back-calculate the ratio of horizontal to vertical soil stress, K*. The load-settlement records were taken from a full-scale field load test, carried out on a single column within an extended group of stone columns. A coupled non-linear finite element formulation was utilised to simulate the test steps and the relevant settlement rate criterion. Post-installation soil parameters were adopted in the simulation in order to account for any vibration- and/or displacement-induced changes in the soil properties. The investigation revealed that the vibro-installation of stone columns significantly alters the soil state of stress. A practical range for the post-installation lateral earth pressure ratio, K*, in the analysed case was deduced. Nous avons etudie les effets de la vibro-installation de colonnes de pier...