Rigorosum Dipl.-Ing. Alexander Dummer
Dipl.-Ing. Alexander Dummer has successfully completed the viva voce examination for his dissertation " Numerical and experimental modeling of the time-dependent, nonlinear constitutive behavior of quasi- brittle materials".
Prize of the Principality of Liechtenstein awarded
Dr Matthias Neuner was awarded the Prize of the Principality of Liechtenstein for his far-reaching research activities.
Habilitation of Dr. Matthias Neuner
Dr. Matthias Neuner was awarded the Venia Docendi for the subject "Applied and Computational Mechanics" on 20.03.2023 after the positive conclusion of his habilitation procedure.
This cumulative habilitation thesis describes important aspects of the highly non-linear and time-dependent material behaviour of cohesive friction materials in several peer-reviewed journal articles. The focus is on the constitutive modelling of these materials with special attention to material failure in numerical simulations, as well as experimental methods for obtaining material parameters for the calibration of such models.
Accordingly, the work is divided into two parts: First, classical and generalised continuum models for cohesive friction materials are presented, investigated and applied in 2D and 3D finite element simulations. Special focus is put on the objective modelling of different failure mechanisms depending on various loading scenarios. In addition to quasi-brittle crack formation under tensile loading, shear band formation under compression and shear loading, crushing under strong multi-axial compression, and time-dependent failure due to creep are dealt with. Subsequently, a comprehensive test programme for characterising the complex material behaviour of hydrating shotcrete is presented, as well as an improved method of the wedge splitting test for determining the specific mode I fracture energy. Finally, several suggestions for future research activities are discussed on the basis of the results presented.