Similar articles

Abstract: This paper presents the results of an experimental research on reinforced concrete beams strengthened with an external carbon fibre reinforced polymer (CFRP) layer under long-term load action that lasted for 330 d. We describe the characteristics of deflection development of the beams strengthened with different additional anchorages of the external carbon fibre composite layer during the period of interest. The conducted experiments showed that the additional anchorage influences the slip of the external layer with respect to the strengthened element. Thus, concrete and carbon fibre composite interface stiffness decreases with a long-term load action. Therefore, the proposed method of analysis based on the built-up-bars theory can be used to estimate concrete and carbon fibre composite interface stiffness in the case of long-term load.

[1]Al Chami, G., Theriault, M., Neale, K.W., 2009. Creep behaviour of CFRP-strengthened reinforced concrete beams. Construction and Building Materials, 23(4):1640- 1652.

[2]Balevičius, R., Dulinskas, E., 2010. On the prediction of non-linear creep strains. Journal of Civil Engineering and Management, 16(3):382-386.

[3]Benyoucef, S., Tounsi, A., Adda Bedia, E.A., Meftah, S.A., 2007a. Creep and shrinkage effect on adhesive stresses in RC beams strengthened with composite laminates. Composites Science and Technology, 67(6):933-942.

[4]Benyoucef, S., Tounsi, A., Benrahou, K.H., Adda Bedia, E.A., 2007b. Time-dependent behavior of RC beams strengthened with externally bonded FRP plates: interfacial stresses analysis. Mechanics of Time-Dependent Materials, 11(3-4):231-248.

[5]Benzaid, R., Chikh, N.E., Mesbah, H., 2008. Behaviour of square concrete column confined with GFRP composite wrap. Journal of Civil Engineering and Management, 14(2):115-120.

[6]Dai, J., Ueda, T., Sato, Y., 2005. Development of the nonlinear bond stress-slip model of fiber reinforced plastic sheet- concrete interfaces with a simple method. Journal of Composites for Construction, 9(1):52-62.

[7]Davis, G.D., Rich, M.J., Drzal, L.T., 2004. Monitoring moisture uptake and delamination in CFRP-reinforced concrete structures with electrochemical impedance sensors. Journal of Nondestructive Evaluation, 23(1):1-9.

[8]Diab, H., Wu, Z., Iwashita, K., 2009. Short and long-term bond performance of prestressed FRP sheet anchorages. Engineering Structures, 31(5):1241-1249.

[9]EN 1992-1, 2001. Eurocode 2: Design of Concrete Structures. Part 1: General Rules and Rules for Buildings. Brussels, Belgium.

[10]Ferrier, E., Hamelin, P., 2002. Long-time concrete-composite interface characterization for reliability prediction of RC beam strengthened with FRP. Materials and Structures, 35(9):564-572.

[11]Ferrier, E., Michel, L., Jurkiewiez, B., Hamelin, P., 2010. Creep behavior of adhesives used for external FRP strengthening of RC structures. Construction and Building Materials, 25(2):461-467.

[12]Fib Task Group 9.3, 2001. Externally Bonded FRP Reinforcement for RC Structures. Fib Bulletin 14, Lausanne, Switzerland, p.130.

[13]Gao, B., Kim, J.K., Leung, C.K.Y., 2003. Effect of rubber modifier on interlaminar fracture toughness of CFRP- concrete interface. Composites Science and Technology, 63(6):883-892.

[14]Kim, Y.J., Wight, R.G., Green, M.F., 2008a. Flexural strengthening of RC beams with prestressed CFRP sheets: Development of nonmetallic anchor systems. Journal of Composites for Construction, 12(1):35-43.

[15]Kim, Y.J., Wight, R.G., Green, M.F., 2008b. Flexural strengthening of RC beams with prestressed CFRP sheets: Using nonmetallic anchor systems. Journal of Composites for Construction, 12(1):44-52.

[16]Lee, Y.J., Boothby, T.E., Bakis, C.E., Nanni, A., 1999. Slip modulus of FRP sheets bonded to concrete. Journal of Composites for Construction, 3(4):161-167.

[17]Livshyc, J.D., 1976. Calculation of Reinforced Concrete Structures with Evaluation of Concrete Shrinkage and Creep. Golovnoe Izdatelstvo Kiev, Russia (in Russian).

[18]Marchukaitis, G., Valivonis, Yu., Bareishis, J., 2007. An analysis of the joint operation of a CFRP concrete in flexural elements. Mechanics of Composite Materials, 43(5):467-478.

[19]Marčiukaitis, G., Jonaitis, B., Valivonis, J., 2006. Analysis of deflections of composite slabs with profiled sheeting up to the ultimate moment. Journal of Constructional Steel Research, 62(8):820-830.

[20]Marčiukaitis, G., Daugevičius, M., Valivonis, J., 2010. The fragmentation of the tensioned zone of the strengthened reinforced concrete beam with carbon fiber composite. Engineering Structures and Technologies, 2(4):129-137 (in Lithuanian).

[21]Rzhanitsyn, A.R., 1986. Built-up Bars and Plates. Strojizdat, Moscow, Russia (in Russian).

[22]Skuturna, T., Valivonis, J., Vainiūnas, P., Marčiukaitis, G., Daugevičius, M., 2008. Analysis of deflections of bridge girders strengthened by carbon fibre reinforcement. The Baltic Journal of Road and Bridge Engineering, 3(3):145-151.

[23]Tan, K.H., Saha, M.K., 2006. Long-term deflections of reinforced concrete beams externally bonded with FRP system. Journal of Composites for Construction, 10(6):474- 482.

[24]Valivonis, J., 2006. Analysis of behaviour of contact between the profiled steel sheeting and the concrete. Journal of Civil Engineering and Management, 12(3):187-194.

[25]Wang, W., Li, G., 2006a. Experimental study and analysis of RC beams strengthened with CFRP laminates under sustaining load. International Journal of Solids and Structures, 43(6):1372-1387.

[26]Wang, W., Li, G., 2006b. Experimental study of RC beams strengthened with CFRP sheets under sustaining loads. Journal of Wuhan University of Technology-Materials Science Edition, 21(3):82-85.

[27]Wang, W., Dai, J., Li, G., Huang, C., 2011. Long-term behavior of prestressed old-new concrete composites beams. Journal of Bridge Engineering, 16(2):275-285.

[28]Weimer, C., Haupert, F., 2000. Influence of aggregate structure on mode-III interfacial fracture between concrete and CFRP. Applied Composite Materials, 7(2-3):183-193.

[29]Xiong, G.J., Jiang, X., Liu, J.W., Chen, L., 2007. A way for preventing tension delamination of concrete cover in midspan of FRP strengthened beams. Construction and Building Materials, 21(2):402-408.