Großversuche zur Querkrafttragfähigkeit bestehender Spannbetonbrücken an der Saalebrücke Hammelburg.

Abstract: In‐situ tests at the bridge Hammelburg regarding the shear capacity of existing pre‐stressed bridges Part 2: Measuring concept, results of the in‐situ tests, comparison with different theoretical approaches Due to the relatively high average age of the existing bridges, a dramatic increase in traffic volume and axle loads and modified design standards, a realistic prediction of the shear capacity of existing pre‐stressed concrete bridges with little shear reinforcement has become an important topic in research. In 2017 the Chair of Concrete and Masonry Structures of the Technical University of Munich (TUM), supported by the Federal Ministry of Transport and Digital Infrastructure, was able to conduct unique field tests at the 1955 built Saalebrücke Hammelburg. According to systematic strength evaluations many concrete bridges, especially those which have been built prior to 1966, show severe (theoretical) deficits regarding the longitudinal shear capacity. Often the results of the strength evaluation cannot be verified at the real bridges though. The primary objective of the field test was therefore to determine the shear capacity of existing pre‐stressed bridges in order to contribute in closing the gap between calculations and experience for older concrete bridges. In the first part of this article the general assessment of the bridge and the original design concept as well as the conceptual approach, the execution of the in‐situ tests and the used measuring equipment were described. In the present paper the measuring concept and the results of the conducted tests are presented. Furthermore, the results of the in‐situ tests are discussed, and the measured maximum loads are compared to the results of different theoretical approaches and engineering models, respectively. [ABSTRACT FROM AUTHOR]