Modal Identification and Dynamic Response Assessment of a Tensairity Girder
Publication: Journal of Structural Engineering
Volume 143, Issue 2
Abstract
The dynamic analysis of a pneumatic beam structure, termed the Tensairity girder, is experimentally, numerically, and analytically studied. The structural concept of Tensairity relies on the combination of an airbeam with conventional struts, which leads in a light-weight structure of significant load-bearing capacity. By focusing on the analysis of the dynamic response of this structure, the objective of this work is to determine the pressure-dependent modal characteristics of the pneumatic beam and to couple these with the associated material properties. Based on the results of a modal identification procedure, relying on hammer and white noise excitation tests, a finite-element (FE) model is updated to reflect the actual system response. This procedure reveals the membrane’s shear modulus as the material property that more heavily relies upon the pressure level of the Tensairity girder. The experimental and numerical investigations indicate that the dynamic behavior of the beam can be expressed as a superposition of pressure dependent and pressure independent modes. The obtained insight allows for a better exploitation of the Tensairity in a new range of applications involving dynamic loading.
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Acknowledgments
This work was in part supported by the Swiss National Science Foundation under Research Grant #200021-143212 titled “Implementation of Wireless Sensor Networks for Monitoring of Large Civil Structures.”
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Published In
Journal of Structural Engineering
Volume 143 • Issue 2 • February 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Aug 5, 2015
Accepted: Jul 12, 2016
Published online: Aug 31, 2016
Discussion open until: Jan 31, 2017
Published in print: Feb 1, 2017
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