عنوان مقاله [English]
In this paper, a strengthening method based on embedded carbon fiber reinforced polymer (CFRP) strips in near surface on concrete cover was applied for improving flexural capacity of reinforced concrete columns with low strength compressive concrete subjected lateral cyclic loads. The debonding phenomena is prevented in this suggested method and the strip capacity is completely used and there is more protection against fire. In order to investigate the flexural behavior of near surface mounted (NSM) strengthened RC columns, a finite element method is sued. poly-linear behavior of concrete and steel was used. There was good similarity between finite element and experimental results that indicates suggested model was calibrated. The new models consisting of different variables such as embedded steel bar diameter, concrete strength, and the numbers of CFRP strips were considered. The test results show that by using the NSM technique, the flexural strength and lateral load capacity of the columns increase significantly. The numerical results were also compared with the results obtained from the analytical study that was conducted based on strain compatibility. A good agreement between analytical and experimental results was observed.
10. Bournas, D., and Triantafillou, T. (2009). “Strengthening of reinforced concrete columns with near-surface-mounted FRP or stainless steel.” ACI Struct. J., 106(4), 495–505.
12. Barros JAO, Dias SJE. (2006). “Near surface mounted CFRP laminates for shear strengthening of concrete beams”, J Cem Concr Compos ;28(3):27692.
13. Mazzolini, S., McKenna, F., Scott, M. H., and Fenves, G. L. (2006). “Open system for earthquake engineering simulation, user command-language manual, Version 2.4.4.” Pacific Earthquake Engineering Research Center, Univ. of California, Berkeley, CA.
14. Menegotto M., Pinto P.E. (1973), “Method of anaysis for cyclically loaded reinforced concreteplane frames including changes in geometry and non-elastic behavior of elements undercombined normal force and bending”, IABSE Symposium of Resistance and UltimateDeformability of Structures Acted on by Well-Defined Repeated Loads, InternationalAssociation of Bridge and Structural Engineering, Libson, Portugal, Vol. 13: 15-22.
15. Designers’ 2005 Guide to EN 1992-1-1 and EN 1992-1-2. Eurocode 2: Design of Concrete Structures. General Rules and Rules for Buildings and Structural Fire Design. A. W. Beeby and R. S. Narayanan. 0 7277 3105 X. Published.
16. Todeschini, C., Bianchini, A.C., and Kesler, C.E. (1964). “Behavior of Concrete Columns Reinforced with Strength Steels”, ACI Journal, Proceedings, 61(6), 701-716.