The dynamic response of fluid-saturated porous materials with application to seismically induced soil liquefaction

• We model liquefaction phenomena in fluid-saturated porous materials.
• We apply a consistent macroscopic continuum description based on the Theory of Porous Media (TPM).
• A tailored elasto-viscoplasticity formulation is used to model flow liquefaction and cyclic mobility.
• The dynamic, coupled multi-field problem is numerically treated by the mixed Finite Element Method (FEM).
• We present the numerical simulation of a realistic soil–structure interaction problem under seismic loading.

The numerical simulation of liquefaction phenomena in fluid-saturated porous materials within a continuum-mechanical framework is the aim of this contribution. This is achieved by exploiting the Theory of Porous Media (TPM) together with thermodynamically consistent elasto-viscoplastic constitutive laws. Additionally, the Finite Element Method (FEM) besides monolithic time-stepping schemes is used for the numerical treatment of the arising coupled multi-field problem. Within an isothermal and geometrically linear framework, the focus is on fully saturated biphasic materials with incompressible and immiscible phases. Thus, one is concerned with the class of volumetrically coupled problems involving a potentially strong coupling of the solid and fluid momentum balance equations and the algebraic incompressibility constraint. Applying the suggested material model, two important liquefaction-related incidents in porous media dynamics, namely the flow liquefaction and the cyclic mobility, are addressed, and a seismic soil–structure interaction problem to reveal the aforementioned two behaviors in saturated soils is introduced.