Ground shaking during earthquakes can be a prominent cause of strength loss in loose saturated soils. In some cases, uncontrolled pore pressure build-up and liquefaction may occur with a time lag with respect to strong ground motion, especially when the time-dependent properties of the soil interact with the constraints brought by undrained and/or partially drained conditions. Here a rate-dependent law based on the critical state theory has been used to replicate the cyclic response of sand by taking into account density effects. The model equations have been inspected to define indices of delayed undrained instability. Then, the model has been calibrated by considering laboratory tests for both monotonic and cyclic undrained loading on loose Hostun sand. Numerical simulations of undrained creep stages following cyclic loading have been performed to illustrate the transition from stable to unstable creep as a function of the number of cycles, thus providing a conceptual framework to evaluate the risk of delayed flow liquefaction in loose sandy deposits.
Modeling Delayed Flow Liquefaction Initiation after Cyclic Loading / Shi, Z.; Marinelli, F.; Buscarnera, G.. - 2018-:292(2018), pp. 212-220. (Intervento presentato al convegno 5th Geotechnical Earthquake Engineering and Soil Dynamics Conference: Numerical Modeling and Soil Structure Interaction, GEESDV 2018 tenutosi a usa nel 2018) [10.1061/9780784481479.022].
Modeling Delayed Flow Liquefaction Initiation after Cyclic Loading
Marinelli F.;
2018
Abstract
Ground shaking during earthquakes can be a prominent cause of strength loss in loose saturated soils. In some cases, uncontrolled pore pressure build-up and liquefaction may occur with a time lag with respect to strong ground motion, especially when the time-dependent properties of the soil interact with the constraints brought by undrained and/or partially drained conditions. Here a rate-dependent law based on the critical state theory has been used to replicate the cyclic response of sand by taking into account density effects. The model equations have been inspected to define indices of delayed undrained instability. Then, the model has been calibrated by considering laboratory tests for both monotonic and cyclic undrained loading on loose Hostun sand. Numerical simulations of undrained creep stages following cyclic loading have been performed to illustrate the transition from stable to unstable creep as a function of the number of cycles, thus providing a conceptual framework to evaluate the risk of delayed flow liquefaction in loose sandy deposits.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.