1. Senior Scientist with Habilitation, Institute for Mechanics of Materials and Structures, Vienna Univ. of Technology (TU Wien), Karlsplatz 13/202, A-1040 Vienna, Austria (corresponding author).
2. Associate Professor, Institute for Mechanics of Materials and Structures, Vienna Univ. of Technology (TU Wien), Karlsplatz 13/202, A-1040 Vienna, Austria.