Creep Deformation of Fiber Reinforced Plastics-Plated Reinforced Concrete Tensile Members
Publication: Journal of Composites for Construction
Volume 9, Issue 1
Abstract
The problem of long-term creep deformation of reinforced concrete tensile elements strengthened by external fiber reinforced plastic (FRP) plates is studied. Formation of discrete cracks in concrete under tension is taken into account. A kinematic model is used, where relative slips between concrete, steel bars, and FRP plates are considered, governed by viscous interface shear stress–slip laws. Bazant’ solidification theory and exponential algorithm are used to obtain incremental constitutive equations for concrete as well as for steel-concrete and FRP-concrete interface laws. Moreover, cohesive normal stresses across transverse cracks in concrete are considered. The incremental differential system of equations is transformed into a nonlinear algebraic system by a finite difference discretization with respect to axial coordinate. Several numerical examples are presented, concerning both short-term and long-term loadings. It is shown that reinforcing by means of FRP plates or sheets has significant beneficial effects on the behavior of reinforced concrete elements under service loadings because (1) it increases concrete tension stiffening effect and (2) it strongly reduces crack width. The present study shows that these beneficial effects are preserved also in the case of long-term loadings.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The financial support of (Italian) MIUR (Ministry of Education, University and Research—PRIN 2003 Grant, FIRB Grant) and C.N.R. (National Council of Research-PAAS Grant 2001) are gratefully acknowledged.
References
Bazant, Z. P. (1971). “Numerically stable algorithm with increasing time steps for integral-type ageing creep.” Proc., 1st Int. Conf. on Structural Mechanics in Reactor Technology, Vol. 3, Paper H2/3.
Bazant, Z. P., and Prasannan, S. (1989a). “Solidification theory for concrete creep. I: Formulation.” J. Eng. Mech., 115(8), 1691–1703.
Bazant, Z. P., and Prasannan, S. (1989b). “Solidification theory for concrete creep. II: Verification and application.” J. Eng. Mech., 115(8), 1704–1725.
Bazant, Z. P., and Wu, S. T. (1974). “Rate-type creep law of aging concrete based on Maxwell chain.” Mater. Struct., 7, 45–60.
Brosens, K., and Van Gemert, D. (1998). “Plate end shear design for extermal CFRP laminates.” Proc., FRAMCOS-3, H. Mihashi and R. Keitetsu, eds., Gifu, Japan, 1793–1804.
Carol, I., and Murcia, J. (1989). “A model for the non linear time-dependent behaviour of concrete in compression based on a Maxwell chain with exponential algorithm.” Mater. Struct., 22, 176–184.
Carol, I., and Bazant, Z. P. (1993).
CEB-FIP. (1997). “CEB Serviceability models. Behaviour and modelling in serviceability limit states including repeated and sustained loads.” Bulletin d’Information n. 235, CEB, Lausanne, Switzerland.
CEB Model Code. (1990). Bulletin d’Information n. 230, Thomas Telford, London.
Ferretti, D., and Savoia, M. (2003). “Cracking evolution in R/C tensile members strengthened by FRP-plates.” Eng. Fract. Mech., 70, 1069–1083.
Hordijk, D. A. (1992). “Tensile and tensile fatigue behaviour of concrete; experiments, modelling and analyses.” Heron, 37(1), 1–77.
Lee, Y. J., Boothby, T. E., Bakis, C. E., and Nanni, A. (1999). “Slip modulus of FRP sheets bonded to concrete.” J. Compos. Constr., 3(4), 161–167.
Mazzotti, C., Ferracuti, B., and Savoia, M. (2004). “An experimental study on FRP—concrete delamination.” Proc., FRAMCOS V Conf., V. C. Li, K. Willam, and C. Leung, eds., Vail, Colo., 1–8.
Mazzotti, C., and Savoia, M. (2001). “An incremental non linear creep damage model for concrete in compression.” Proc., ECCM-2001 Conference, Z. Waszczyszyn, ed., Cracow, Poland, 1–16.
Mazzotti, C., and Savoia, M. (2002). “Nonlinear creep, Poisson’s ratio, and creep-damage interaction of concrete in compression.” ACI Mater. J., 99(5), 450–457.
Mazzotti, C., and Savoia, M. (2003). “Nonlinear creep damage model for concrete under uniaxial compression.” J. Eng. Mech., 129(9), 1065–1075.
Plevris, N., and Triantafillou, T. C. (1994). “Time-dependent behavior of RC members strengthened with FRP laminates.” J. Struct. Eng., 120(3), 1016–1042.
Sato, R., Ujike, I., Akita, K., and Kasai, N. (1987). “Properties of bond under sustained loading at an early age.” Trans. Jpn. Concr. Inst., 9, 257–264.
Sato, Y., Shouji, K., Ueda, T., and Kakuta, Y. (1999). “Uniaxial tensile behavior of reinforced concrete elements strengthened by carbon fiber sheets.” Proc., FRPRCS-4 Int. Symp., ACI SP-188, Dolan, Rizkalla and Nanni, eds., 697–710.
Savoia, M., Ferretti, D., and Mazzotti, C. (2002). “Creep behavior of RC tensile elements retrofitted by FRP plates.” Proc., ICCI’02 Conf., Saadatmanesh and Ehsani, eds., San Francisco, 1–12.
Savoia, M., Ferracuti, B., and Mazzotti, C. (2003a). “Creep deformation of FRP-plated R/C tensile elements using solidification theory.” Proc., Comp. Modelling of Concrete Structures—EURO-C, Bicanic et al., eds., St. J. im Pongau, Austria, Lisse, Balkema, Rotterdam, The Netherlands, 501–511.
Savoia, M., Ferracuti, B., and Mazzotti, C. (2003b). “Non linear bond-slip law for FRP-concrete interface.” Proc., FRPRCS-6 Conf., K. H. Tan, ed., Singapore, 1–10.
Tripi, J. M., Bakis, C. E., Boothby, T. E., and Nanni, A. (2000). “Deformation in concrete with external CFRP sheet reinforcement.” J. Compos. Constr., 4(2), 85–94.
Zienkiewicz, O. C., and Watson, M. (1966). “Some creep effects in stress analysis with particular references to concrete pressure vessels.” Nucl. Eng. Des., 4, 406–412.
Information & Authors
Information
Published In
Copyright
© 2004 ASCE.
History
Received: Aug 4, 2003
Accepted: May 3, 2004
Published online: Feb 1, 2005
Published in print: Feb 2005
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.