Theoretical and Numerical Investigations of Swelling Phenomena of Hydrated Porous Media

• Applicant: Professor Dr.-Ing. Wolfgang Ehlers
• Subject Area: Mechanics
• Term: from 2003 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5470270

The macroscopic behaviour of biomaterials like hard and soft tissues, artificial materials like hydrogel or geomaterials like clay and shale ist governed by the multiphysic microstructure together with dissipative phenomena and various electrochemomechanical couplings on the microscale. Furhtermore, flowindependent (intrinsic) viscoelastic properties of the solid matrix are strongly coupled with the flow-dependent viscous effects resulting from hydraulic and electrochemical gradients. Thus, one obtains a fully coupled electro-chemomechanical problem including swelling and, vice versa, shrinking phenomena at absolutely finite deformations. Based on the Theory of Porous Media (TPM), it is the goal of this project to deliver a proper formulation of both the theoretical and the numerical description of a solid-fluid aggregate, where negative charges are fixed to the solid skeleton and positive and negative ions are includetd into the pore-fluid. The innovation of the this project which is closely related to a thermatically neighboured proposal by our Dutch partner Dr. Jacques Huyghe lies in both the theoretical formulation of a fully coupled electro-chemomechanical model at absolutely finite 3-dimensional viscoelastic deformations of the hydrated solid and the numerical treatment of the multiphasic model in the framework of the FEM based on the FE tool PANDAS.

• DFG Programme: Research Units
• Subproject of: FOR 509: Multiscale Methods in Computational Mechanics
• Participating Person: Professor Dr.-Ing. Bernd Markert