Experimental Evaluation of Tensile Forces in Short Steel Rods

Abstract:

There are a lot of structures in building and civil engineering where the significant structural elements are loaded by large tensile forces (e.g. tension bars of building structures). In many practical cases it is important to know the actual value of tensile forces in tensile structural elements for assessment of their reliability. The four experimental techniques are used for determination of tensile forces in practice most often. The vibration frequency method, which is one of them, is very suitable for experiments done only one time or sometimes, especially in cases when the examined structural elements are already activated and the application of an experimental method is necessary in this situation. The experiment described in this paper was focused on the tensile force determination in steel rods, which were very short and relatively stiff. The evaluated tensile forces of the investigated short steel rods were affected by a significant error when only the simplest models (the string model, the simply supported beam and the fixed beam) and measured natural frequencies were applied. In order to precise the determined tensile forces, the theoretical beam model supported by simple supports with torsion springs (“the elastically fixed beam”) and the measured natural modes of the rods had to be necessarily taken into account.

• Periodical: Applied Mechanics and Materials (Volume 732)
• Pages: 333-336
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.732.333
• Online since: February 2015
• Authors: Michal Polak*, Tomáš Plachy
• Keywords: Cable, Experiment, Natural Frequency, Natural Mode, Prestressing Force, Steel Rod, Tensile Force

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