Flexural Behavior of Hybrid FRP-Concrete-Steel Double-Skin Tubular Members
Publication: Journal of Composites for Construction
Volume 10, Issue 5
Abstract
This paper presents the results of an experimental study on the flexural behavior of a new type of hybrid FRP-concrete-steel member as well as results from a corresponding theoretical model based on the plane section assumption and the fiber element approach. This new type of hybrid member is in the form of a double-skin tube, composed of a steel inner tube and an FRP outer tube with a concrete infill between the two tubes, and may be employed as columns or beams. The parameters examined in this study include the section configuration, the concrete strength, and the thicknesses of the steel tube and the FRP tube, respectively. The results presented in this paper show that these hybrid beams have a very ductile response because the compressive concrete is confined by the FRP tube and the steel tube provides ductile longitudinal reinforcement. The beams' flexural response, including the flexural stiffness, ultimate load, and cracking, can be substantially improved by shifting the inner steel tube toward the tension zone or by providing FRP bars as additional longitudinal reinforcement. The predictions from the theoretical model are in reasonably close agreement with the test results. Differences between the test and predicted results arise from factors not considered in the theoretical model, including the existence of a strain gradient in the confined concrete, concentrations of cracks and the slips between the concrete and the two tubes; these are issues to be accounted for in the development of a more accurate model in the future.
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Acknowledgments
The work presented in this paper has received financial support from the Hong Kong Polytechnic University through a research studentship to the first author and the Young Professorship Scheme (Project No: 1ZE-06) and through a Distinguished Young Scholar Award of the Natural Science Foundation of China (Project No. 50329802). The authors are grateful to both organizations for their financial support.
References
ACI 440.3R. (2004). Guide test methods for fiber-reinforced polymers (FRPs) for reinforcing or strengthening concrete structures, ACI Committee 440, Farmington Hills, Mich.
ASTM D 3039. (2000). Standard test method for tensile properties of polymer matrix composite materials, ASTM Committee D30, Philadelphia.
BS 18. (1987). Tensile testing of metals (including aerospace materials), British Standards Institution, London, U.K.
Fam, A. Z., and Rizkalla, S. H. (2001). “Behavior of axially loaded concrete-filled circular fiber-reinforced polymer tubes.” ACI Struct. J., 98(3), 280–289.
Fam, A. Z., and Rizkalla, S. H. (2002). “Flexural behavior of concrete-filled fiber-reinforced polymer circular tubes.” J. Compos. Constr., 6(2), 123–132.
Han, B., Xia, J., and Zhao, J. (1995). “The strength of concrete filled double-skin steel tubes under axial compression.” Journal of Shijiazhuang Railway Institute, 8(3), 75–80.
Mirmiran, A., Shahawy, M., and Samaan, M. (1999). “Strength and ductility of hybrid FRP-concrete beam-columns.” J. Struct. Eng., 125(10), 1085–1093.
Shahawy, M., Mirmiran, A., and Beitelman, T. (2000). “Tests and modeling of carbon-wrapped concrete columns.” Composites, Part B, 31(6–7), 471–480.
Shakir-Khalil, H. (1991). “Composite columns of double-skinned shells.” J. Constr. Steel Res., 19, 133–152.
Shakir-Khalil, H., and Illouli, S. (1987). “Composite columns of concentric steel tubes.” Proc., Conf. on the Design and Construction of Non-Conventional Structures, Vol. 1, London, pp. 73–82.
Tao, Z, Han, L. H., and Huang, H. (2003). “Concrete-filled double-skin steel tubular column with square section under eccentric loads.” China Civ. Eng. J., 36(2), 33–40.
Teng, J. G., Chen, J. F., Smith, S. T., and Lam, L. (2002). FRP strengthened RC structures, John Wiley & Sons Ltd., New York.
Teng, J. G., and Lam, L. (2004). “Behavior and modeling of FRP-confined concrete.” J. Struct. Eng., 130(11), 1713–1723.
Teng, J. G., Yu, T., and Wong, Y. L. (2004). “Behavior of hybrid FRP-concrete-steel double-skin tubular columns.” Proc., 2nd Int. Conf. on FRP Composites in Civil Engineering, Adelaide, Australia, 811–818.
Teng, J. G., Yu, T., Wong, Y. L., and Dong, S. L. (2005). “Hybrid FRP-concrete-steel tubular columns: Concept and behavior.” Constr. Build. Mater., accepted for publication.
Wei, S., et al. (1995). “Performance of new sandwich tube under axial loading: Experiment.” J. Struct. Eng., 121(12), 1806–1814.
Yagishita, F., Kitoh, H., Sugimoto, M., Tanihira, T., and Sonoda, K. (2000). “Double-skin composite tubular columns subjected to cyclic horizontal force and constant axial force.” Proc., 6th ASCCS Int. Conf. on Steel-Concrete Composite Structures, 497–503.
Zhao, X. L., Grzebieta, R., and Elchalakani, M. (2002). “Tests of concrete-filled double-skin CHS composite stub columns.” Steel Compos. Struct., 2(2), 129–146.
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© 2006 ASCE.
History
Received: Oct 28, 2005
Accepted: Jan 12, 2006
Published online: Oct 1, 2006
Published in print: Oct 2006
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