1. Professor, Institute of Structural Engineering (IKI), Hochschule Biberach University of Applied Sciences, Biberach/Riß, Germany
2. Team Manager Anchoring Systems, Research – Development – Engineering, Halfen GmbH, Langenfeld, Germany
3. Professor, Institute of Structural Concrete (IMB), RWTH Aachen University, Aachen, Germany (corresponding author: )