1. Research Associate, Infrastructure Management Group (IMG), Institute of Construction and Infrastructure Management, Swiss Federal Institute of Technology in Zurich, Inst. Bau-&Infrastrukturmanagement, HIL F 22.2, Stefano-Franscini-Platz 5, 8093 Zürich, Switzerland (corresponding author).
2. Professor, Infrastructure Management, Institute of Construction and Infrastructure Management, Swiss Federal Institute of Technology in Zurich, Inst. Bau-&Infrastrukturmanagement, HIL F 24.3, Stefano-Franscini-Platz 5, 8093 Zürich, Switzerland.