Untersuchung des Auszugsverhaltens von Polymerfasern in zementgebundenen Materialien
Source: BAM
Cementitious composites showing a ductile behavior, so-called Strain Hardening Cementitious Composites (SHCC), are suitable for applications with extreme mechanical loads. The ductile fracture behavior under tensile loads is solely obtained by the addition of polymer fibers. The tensile behavior of the polymer fibers as well as their pull-out behavior determine the performance of this composite material and are crucial for an aimed optimization. The single fiber pull-out test (SFPT) is the standard characterization technique for testing the bond strength of polymer fibers.
However, the different phases of debonding cannot be distinguished by ‘classical’ force and displacement measuring techniques as applied by the SFPT in its standard configuration. Therefore, a modified test setup was developed in cooperation with the Rosenheim Technical University of Applied Sciences. This modified SFPT allows for a better characterization of the different phases of debonding. Besides linear variable differential transformers (LVDT), non-destructive testing methods have been used. The application of Digital Image Correlation (DIC) in combination with linear variable differential transformers allows for a comprehensive analysis of the deformation behavior of a single fiber and thus for a precise identification of the different phases of debonding during fiber pull-out.
Analyzing the pull-out behavior of polymer fibers in cementitious materials
Michael Sigrüner, Götz Hüsken, Stephan Pirskawetz, Jonas Herz, Dirk Muscat, Nicole Strübbe
Journal of Polymer Science 2023, Volume 61, Issue 21, Pages 2708-2720