Radial spherical plain bearings as components of the control-rod system Meyer/Wunstorf - Durability test results of radial spherical plain bearings exposed to cyclic loading

Since the mid-70s in Germany the control-rod system "Meyer/Wuns-torf" is a proven design of a longitudinal bridge support system especially for railway bridges. Horizontal forces due to braking and acceleration can thus be evenly distributed to both abutments. In contrast to one-sided longitudinal supported bridges also the temperature-related linear expansion of the superstructure can be distributed equally to both abutments by realizing a fictitious zero point of strain in the middle of the bridge. Thus, larger spans with continuous rails, without rail expansions, can be built. The kinematic control-rod design incorporates some highly loaded hinge pin connections for which so-called radial spherical plain bearings (RGL) are used. For civil constructions these bearings are rather unusual, hitherto not regulated and currently requiring technical and corporate approvals for individual cases (ZiE/UiG). This paper reports - including a short introduction to the topic - on the results of durability tests on RGL, which have been carried out in 2014 by the Chair for Metal Structures of the TU Munchen (Technical University of Munich) in the context of technical approvals for current projects of the Deutsche Bahn.