SFB 1313 Publication "A variational minimization formulation for hydraulically induced fracturing in elastic-plastic solids"

New SFB 1313 publication (University of Stuttgart), published in International Journal of Fracture. The paper has been prepared within SFB 1313's research project B01:

"A variational minimization formulation for hydraulically induced fracturing in elastic-plastic solids"

Authors

• Daniel Kienle (University of Stuttgart, SFB 1313 research projects B01)
• Marc-André Keip (University of Stuttgart, SFB 1313 research projects B01)

Abstract

A variational modeling framework for hydraulically induced fracturing of elastic-plastic solids is developed in the present work. The developed variational structure provides a global minimization problem. While fracture propagation is modeled by means of a phase-field approach to fracture, plastic effects are taken into account by using a Drucker–Prager-type yield-criterion function. This yield-criterion function governs the plastic evolution of the fluid-solid mixture. Fluid storage and transport are described by a Darcy–Biot-type formulation. Thereby the fluid storage is decomposed into a contribution due to the elastic deformations and one due to the plastic deformations. A local return mapping scheme is used for the update of the plastic quantities. The global minimization structure demands a H(div)-conforming finite-element formulation. Furthermore this is combined with an enhanced-assumed-strain formulation in order to overcome locking phenomena arising from the plastic deformations. The robustness sand capabilities of the presented framework will be shown in a sequence of numerical examples.