Time-Dependent Behavior of FRP Retrofitted RC Columns after Subjecting to Simulated Earthquake Loading
Publication: Journal of Composites for Construction
Volume 18, Issue 1
Abstract
Seismic retrofit of reinforced concrete (RC) columns using fiber-reinforced plastic (FRP) jacketing has been widely investigated. However, the residual performance of FRP retrofitted columns after surviving earthquake attacks remains as an issue with little research. As a follow up of a previous experimental study, this paper reports the analysis of the axial loading creep behavior of FRP retrofitted RC columns with different degrees of simulated earthquake damage. The damage degree and residual strains in FRP after lateral loading are assessed based on previous maximum lateral displacement excursion. A creep model for damaged columns with FRP jacket is presented based on the age-adjusted effective modulus method for creep of concrete and the Findley’s power law function for creep of FRP jacket. The creep model considers the effects of previous damage, sealed concrete, multiaxial stress state of stresses and stress redistribution. The proposed model is validated against previous creep tests of fiber-wrapped concrete columns by other researchers and the long-term tests conducted by the authors. Finally, a detailed study is carried out to identify the practical design parameters affecting creep of hybrid columns. The analytical results show that the creep of the FRP confined column increases as the damage degree becomes larger and exhibits notable nonlinear feature. The creep life declines and may cause creep rupture of the FRP when retrofitted columns suffer serious earthquake damage or under high axial load.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
Primary support for this study was provided by the National Key Basic Research Program of China (973-2012CB026200) and the National Natural Science Foundation of China (NSFC Grant No. 50278032). Supplemental support for the second author was provided by the One-Thousand Talent National Expert Program.
References
ACI Committee 209. (1971). “Prediction of creep, shrinkage and temperature effects in concrete structures.” Design for the effects of creep, shrinkage and temperature, Detroit, 51–93.
ACI Committee 209. (1992). “Prediction of creep, shrinkage and temperature effects in concrete structures (ACI 209R-92).” American Concrete Institute, Farmington Hills, MI.
Bazant, Z. P. (1972). “Prediction of concrete creep effects using age-adjusted effective modulus method.” ACI J., 69(20), 212–217.
Findley, W. N. (1960). “Mechanism and mechanics of creep of plastics.” SPE J., 57–65.
Gopalkrishnan, K. S., Neville, A. M., and Ghali, A. (1970). “A hypothesis on mechanism creep of concrete with reference to multiaxial compression.” ACI J., 67(3), 29–35.
Harajli, M. H., and Rteil, A. (2004). “Effect of confinement using FRP or FRC on seismic performance of gravity load-designed columns.” ACI Struct. J., 101(1), 47–56.
Hollaway, L. C., and Teng, J. G. eds. (2008). Strengthening and rehabilitation of civil infrastructures using FRP composites, Woodhead Publishing, Cambridge, UK.
Jordaan, I. J., and Illston, J. M. (1971). “Time-dependent strains in seals concrete under multiaxial compressive stress.” Magazine of concrete research, 23(75), 78–88.
Ma, R., and Xiao, Y. (1999). “Seismic retrofitting and repairing of circular bridge columns with advanced composite materials.” Earthquake Spectra, 15(4), 747–764.
Naguib, W., and Mirmiran, A. (2002). “Time-dependent behavior of fiber-reinforced polymer confined columns under axial loads.” ACI Struct. J., 99(2), 142–148.
Naguib, W., and Mirmiran, A. (2003). “Creep analysis of axially loaded fiber reinforced polymer-confined concrete columns.” J. Engineering Mechanics, 129(11), 1308–1319.
Neville, A. M. (1970). Creep of concrete: Plain, reinforced and prestressed, North-Holland Publishing Company, Amsterdam.
Park, Y. J., and Ang, H. S. (1985). “Mechanistic seismic damage model for reinforced concrete.” J. Struct. Eng., 722–739.
Purba, B. K., and Mufti, A. A. (1999). “Investigation of the behavior of circular concrete columns reinforced with carbon fiber reinforced polymer (CFRP) jackets.” Can. J. Civ. Eng., 26(5), 590–596.
Russel, H. G., and Corley, W. G. (1977). “Time-dependent behavior of columns in water tower place.” Research and development Bulletin RD025B, Portland Cement Association, Skokie, IL.
Saadatmanesh, H., and Ehsani, M. R. (1994). “Strength and ductility of concrete columns reinforced with fiber composite straps.” ACI Struct. J., 91(4), 434–447.
Saadatmanesh, H., Ehsani, M. R., and Jin, L. (1996). “Seismic strengthening of circular bridge pier models with fiber composite straps.” ACI Struct. J., 93(6), 639–647.
Shan, B., Xiao, Y., and Guo, Y. R. (2006). “Residual performance of FRP-retrofitted RC columns after being subjected to cyclic loading.” J. Compos. Constr., 304–320.
Sheikh, A. S., and Yau, G. (2002). “Seismic behavior of concrete columns confined with steel and fiber-reinforced polymers.” ACI Struct. J., 99(1), 72–80.
Teng, J. G., and Lam, L. (2004). “Behavior and modeling of fiber reinforced polymer-confined concrete.” J. Struct. Eng., 1713–1723.
Xiao, Y. (2004). “Applications of FRP composites in concrete columns.” Int. J. Adv. Struct. Eng., 7(4), 335–344.
Xiao, Y., and Ma, R. (1997). “Seismic retrofit of RC circular columns using prefabricated composite jacketing.” J. Struct. Eng., 1357–1364.
Xiao, Y., and Wu, H. (2000). “Compressive behavior of concrete cylinders confined by carbon fiber composite jackets.” J. Mater. Civil Eng., 139–146.
Xiao, Y., Wu, H., and Martin, R. (1999). “Prefabricated composite jacketing of RC columns for enhanced shear strength.” J. Struct. Eng., 255–264.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 18 • Issue 1 • February 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Feb 4, 2013
Accepted: Jun 21, 2013
Published online: Oct 16, 2013
Published in print: Feb 1, 2014
Discussion open until: Mar 16, 2014
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.