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A Fully Coupled Flow-Deformation Model for Dynamic Analysis of Unsaturated Soils Including Hydraulic and Mechanical Hystereses
Nasser Khalili, The University of New South Wales Chair: Qing Li Time: 2019/12/20 14:00-14:40 (102, 1F, TICC) |
Abstact:
Dynamics of multi-phase porous materials is of interest to many branches of engineering and science including geophysics, seismology, acoustics, biomechanics, reservoir engineering, pavement engineering, and fracture mechanics. Numerous contributions have been made to dynamics of porous materials in the past few decades. However, they have mostly been limited to the analysis of single-phase fully drained (dry) or two-phase fully saturated porous media. A fully coupled flow-deformation model is presented in this paper for the dynamic analysis of unsaturated soils. The coupling between fluid flow and deformation fields is established using the effective stress approach. The hydraulic hysteresis is accounted for in the model through the effective stress parameters and the soil water characteristic curve. The volume change dependency of the effective stress parameters and the soil water characteristic curve is addressed in the formulation. The elastic-plastic behaviour due to cyclic loading is captured using the bounding surface plasticity theory. Simulation results are presented and the effects of hydraulic hysteresis on static and dynamic response of unsaturated soils are particularly emphasised.
Dynamics of multi-phase porous materials is of interest to many branches of engineering and science including geophysics, seismology, acoustics, biomechanics, reservoir engineering, pavement engineering, and fracture mechanics. Numerous contributions have been made to dynamics of porous materials in the past few decades. However, they have mostly been limited to the analysis of single-phase fully drained (dry) or two-phase fully saturated porous media. A fully coupled flow-deformation model is presented in this paper for the dynamic analysis of unsaturated soils. The coupling between fluid flow and deformation fields is established using the effective stress approach. The hydraulic hysteresis is accounted for in the model through the effective stress parameters and the soil water characteristic curve. The volume change dependency of the effective stress parameters and the soil water characteristic curve is addressed in the formulation. The elastic-plastic behaviour due to cyclic loading is captured using the bounding surface plasticity theory. Simulation results are presented and the effects of hydraulic hysteresis on static and dynamic response of unsaturated soils are particularly emphasised.
