Laboratory Tests and Numerical Analyses of Prefabricated Timber-Concrete Composite Floors
Publication: Journal of Structural Engineering
Volume 136, Issue 1
Abstract
This paper describes tests on a novel composite floor system constructed by connecting prefabricated concrete slabs to timber joists. Seven types of shear connectors have been developed and tested: lag screws, either alone or combined with a notch cut from each timber joist; metal plates embedded in the concrete slab and either nailed or glued to the joists; dowels embedded in the concrete and glued to the timber; and toothed metal plates embedded in the concrete and pressed into the timber. Four-point bending tests to failure were performed on five, full-scale, 4.8 m long specimens connected with lag screws or metal plates nailed to the timber. Values of deflection and relative slip between the concrete slab and the timber obtained in these tests showed high correspondence with values obtained from a uniaxial finite element model developed for nonlinear analyses of composite beams. The model was also used to perform a numerical analysis to failure of composite beams with the other four connection systems that were developed but not tested on full-scale specimens. The outcomes of the experimental tests and numerical analyses show that the newly developed system can provide good structural performance, especially if connections with coach screws and notches in the timber are used. The economic advantages of prefabrication and the possibility to disassemble the structure and reuse the timber beams and concrete panels at the end of the service life make the proposed floor system very promising.
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Acknowledgments
The writers gratefully acknowledge financial support for the project granted by the Lars Erik Lundberg Scholarship Foundation and the Stiftelsen J. Gust. Richerts Minne. The described work was conducted at Luleå University of Technology (LTU) in Sweden. Complab Laboratory at Civil and Environmental Engineering Department at LTU is gratefully acknowledged for providing facilities for the experimental work. Thanks are also extended to the laboratory technicians for their invaluable help and advice in this work.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 136 • Issue 1 • January 2010
Pages: 46 - 55
Copyright
© 2010 ASCE.
History
Received: Nov 11, 2008
Accepted: May 20, 2009
Published online: Jun 17, 2009
Published in print: Jan 2010
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