Modal Frequencies of a Reinforced Timber-Concrete Composite Floor: Testing and Modeling
Publication: Journal of Structural Engineering
Volume 141, Issue 11
Abstract
The reinforcement of a timber floor with a concrete layer properly connected to produce a composite system represents not only an improvement in the stiffness but also a foreseeable change in the modal frequencies of the floor. In order to assess that change, a typical timber floor, which was subsequently reinforced with a concrete layer to produce a composite, was tested at both stages in the research reported in this paper. Additionally, composite beams taken from the original floor were also tested. The results showed a significant decrease (44%) in the fundamental frequency after the reinforcement. In order to obtain the mode shapes and frequencies of the floor, finite-element (FE) models of the floors and beams were created. The FE models accurately matched the experimental results. Having validated the model, a parametric study was carried out to compare the results provided by the proposed FE model with a numerical model from the bibliography and to understand the influence of the most relevant structural parameters on the fundamental frequency of the composite floor.
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Acknowledgments
The writers wish to thank the Portuguese Foundation for Science and Technology (FCT) and the Science and Innovation Operational Program cofinanced by the European Union Fund Fundo Europeu de Desenvolvimento Regional (FEDER), for the support provided through the Research Project No. PTDC/ECM/099833/2008.
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Published In
Journal of Structural Engineering
Volume 141 • Issue 11 • November 2015
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Apr 14, 2014
Accepted: Jan 7, 2015
Published online: Feb 19, 2015
Discussion open until: Jul 19, 2015
Published in print: Nov 1, 2015
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