1. University Assistant, Institute for Mechanics of Materials and Structures, Vienna Univ. of Technology, Karlsplatz 13/202, A-1040 Vienna, Austria.
2. Univ. Dozent, Institute for Mechanics of Materials and Structures, Vienna Univ. of Technology, Karlsplatz 13/202, A-1040 Vienna, Austria (corresponding author).
3. Professor, Institute for Mechanics of Materials and Structures, Vienna Univ. of Technology, Karlsplatz 13/202, A-1040 Vienna, Austria.