Dynamisches Mehrphasenmodell mit hypoplastischer Materialformulierung der Feststoffphase
type: CreativeWork
description: The numerical simulation of heterogeneous materials with solid and pore filling fluid phases becomes more and more important in different areas of engineering practice due to the availability of high performance computers. The classical application area of multiphase models is the investigation of complex geotechnical problems considering the influence of the pore fluid on the bearing behaviour of soils. In addition to simple consolidation the model is applicable for the simulation of the phenomenon of soil liquefaction initiated by earthquake induced failures in saturated or partially saturated soils. Further applications in geotechnical engineering like water drainage using compressed air and sump drainage contain active generated flows, where the water within the soil is pushed away by compressed air or pumped down by a negative pressure. Fluid flows and transport processes can also be found in other areas like oil-production, material science and biomechanics.The present work aims at developing a stable and reliable multiphase model with nonlinear material formulation for the solid phase, that can applied to most of the geotechnical problems. Up to now, such a general applicable model is not available in the literature.The derivation of the multiphase model is based on the theory of porous media in which the material mixture is divided into its components solid phase, water and air. By using the principle of effective stresses and enhanced Darcy equations for two fluids the mass balance equations of the constitutive phases are evaluated. The resulting differential equations are approximated by the finite element method. The variable implementation of the numerical integration according to Gauß allows the automatic adjustment of the integration degree in case of a discontinuous saturation fronts.The formulation of the deformable granular structure is represented by the hypoplasticity and its extension by the intergranular strain approach. This material law allows…
abstract: The numerical simulation of heterogeneous materials with solid and pore filling fluid phases becomes more and more important in different areas of engineering practice due to the availability of high performance computers. The classical application area of multiphase models is the investigation of complex geotechnical problems considering the influence of the pore fluid on the bearing behaviour of soils. In addition to simple consolidation the model is applicable for the simulation of the phenomenon of soil liquefaction initiated by earthquake induced failures in saturated or partially saturated soils. Further applications in geotechnical engineering like water drainage using compressed air and sump drainage contain active generated flows, where the water within the soil is pushed away by compressed air or pumped down by a negative pressure. Fluid flows and transport processes can also be found in other areas like oil-production, material science and biomechanics.The present work aims at developing a stable and reliable multiphase model with nonlinear material formulation for the solid phase, that can applied to most of the geotechnical problems. Up to now, such a general applicable model is not available in the literature.The derivation of the multiphase model is based on the theory of porous media in which the material mixture is divided into its components solid phase, water and air. By using the principle of effective stresses and enhanced Darcy equations for two fluids the mass balance equations of the constitutive phases are evaluated. The resulting differential equations are approximated by the finite element method. The variable implementation of the numerical integration according to Gauß allows the automatic adjustment of the integration degree in case of a discontinuous saturation fronts.The formulation of the deformable granular structure is represented by the hypoplasticity and its extension by the intergranular strain approach. This material law allows…
author: Holler, Stefan
language: ger
keywords: info:eu-repo/classification/ddc/620, Ingenieurwissenschaften, Mehrphasenströmung, Plastizität, Dynamik, Biomechanik, Mehrphasensystem, Porosität, Finite-Elemente-Methode, hypoplasticity, intergranular strain
date published: 2006
date modified: 2026-07-30T19:43:02Z
provider: RWTH Aachen University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Publikationsserver der RWTH Aachen University