1. Univ. Lecturer in Structural Engineering, Dept. of Engineering, Univ. of Cambridge, Trumpington St., Cambridge CB2 1PZ, U.K.
2. Researcher, Swiss Federal Laboratories for Materials Testing and Research (EMPA), Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
3. Director, Swiss Federal Laboratories for Materials Testing and Research (EMPA), Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.