Experimental and Numerical Study of Damaged Cantilever
Publication: Journal of Engineering Mechanics
Volume 126, Issue 1
Abstract
The introduction of a crack in a steel structure will cause a local change in the stiffness and damping capacity. The change in stiffness will lead to a change of some of the natural frequencies of the structure and a discontinuity in the associated mode shapes. This paper contains a presentation of the results from experimental and numerical tests with hollow section cantilevers containing fatigue cracks. Two different finite-element (FE) models have been used to estimate the modal parameters numerically. The first FE model consists of beam elements. The second FE model consists of traditional rectangular shell elements and one rectangular shell element with a transverse, internal, open crack. The analytical results from the numerical models are compared with data obtained from experimental tests. The numerical models give good agreements with the experimental data. The beam model takes into account only the first mode of the crack evaluation. In the shell model all three modes of the crack growth are taken into account. Nevertheless, the results obtained for both models are satisfactory because the beam is subjected to bending. It can be concluded that it is sufficient to use crack models for calculating natural frequencies in bending, taking into account the first mode of the crack extension only.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 126 • Issue 1 • January 2000
Pages: 60 - 65
History
Received: Oct 9, 1995
Published online: Jan 1, 2000
Published in print: Jan 2000
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