Zugkrafteinleitung in Beton bei mehraxialen Belastungsversuchen

Tension load transfer to concrete at multiaxial loading tests

Multiaxial stress states have a significant influence on the material behaviour of concrete. Besides a strength increasing or decreasing effect, such stress states lead to changes of the stress-strain-behaviour. For the investigation of the material behaviour of concrete under multiaxial loading it is necessary to conduct experimental studies. Within the scope of multiaxial tests with ultra high performance concrete with small tension in the one and high compression loads in the other two directions it was observed, that the concrete failed close to the surface where the tensile force was initiated or, respectively, that the load transfer device detach from the specimen's surface. Because of theoretical consideration it was clear, that the achieved strength values at the tests couldn't be the "real" material strength values. Therefore, the method of tension load transfer had to be improved. After the development of a new tension load transfer method, significant higher strength values could be obtained at the tests. These values also pass the theoretically prescribed limit for "real" material strength, which was determined on experimental strength values where clearly material failure occurred.