Hochbelastete Lastübertragungszonen mit stumpf gestoßener Bewehrung: Experimentelle Untersuchungen und numerische Simulationen

Highly stressed load transfer zones with butt jointed reinforcement: Experimental investigations and numerical simulations. In modern tunnel constructions the use of tunnel boring machines (TBMs) and precast tunnel segments is internationally established. In this construction method, the design of the longitudinal joint, which can be regarded as a dry butted load transfer zone, presents a particular challenge due to its geometric boundary conditions and possible installation tolerances. The reinforcement concept developed by TU Wien, which forms the basis of this publication, offers a possibility for the design of a longitudinal joint. The use of butt-jointed longitudinal reinforcement bars in load transfer zones under compression results in an increase in ultimate load that corresponds to the ultimate load capacity of the butt-jointed longitudinal bars. This is verified by means of experimental tests and numerical simulations. Experimental investigations and numerical simulations on specimens with a spacing between the end faces and/or an eccentricity of the longitudinal bars showed significantly lower increases in ultimate load. By taking suitable measures during segment production and by selecting the bar diameter of the longitudinal reinforcement, taking into account the expected installation tolerances, the increases in ultimate load of the reinforcement concept developed at TU Wien can also be implemented in practice. © 2022, Ernst und Sohn. All rights reserved.