Small-Scale Modeling of Reinforced Concrete Structural Elements for Use in a Geotechnical Centrifuge
Publication: Journal of Structural Engineering
Volume 137, Issue 11
Abstract
This paper discusses the modeling of reinforced concrete structural elements for use in geotechnical centrifuge modeling of soil-structure interaction problems. Centrifuges are employed in geotechnical modeling so that the nonlinear constitutive behavior of soil in small-scale models can be correctly modeled at prototype scale. Such models typically necessitate large scale factors of between and , which is significantly larger than most conventional small-scale structural modeling. A new model concrete has been developed consisting of plaster, water, and fine sand as a geometrically scaled coarse aggregate that can produce a range of model concretes with cube compressive strengths between 25–80 MPa. Reinforcement is modeled using roughened steel wire (beams) or wire mesh (slabs). To illustrate the validity of the modeling technique, a series of three- and four-point bending tests were conducted on model beams designed to represent a square section prototype beam at scale, and model slabs designed to represent a prototype slab with plan dimensions of and 0.4 m deep (also at scale). The amount of longitudinal reinforcement was varied and tests both with and without shear reinforcement were conducted. The models were able to accurately reproduce both shear and flexural (bending) failures when loaded transversely. The load capacity (strength), bending stiffness, and ductility were shown to be simultaneously and appropriately scaled over a range of scaling factors appropriate for geotechnical centrifuge testing, and the technique therefore provides a significant improvement in the ability to accurately model soil-structure interaction behavior in centrifuge models.
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Acknowledgments
The authors would like to sincerely thank Ernie Kuperus and the technical staff of the Division of Civil Engineering for their assistance in manufacturing the testing equipment and formwork, and to Mark Truswell for his assistance with the testing programme. The authors would also like to acknowledge the support of the Nuffield Foundation, UK for funding the second author’s summer internship at the University of Dundee.
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© 2011 American Society of Civil Engineers.
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Received: Jul 29, 2009
Accepted: Dec 27, 2010
Published online: Dec 29, 2010
Published in print: Nov 1, 2011
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