Journal of Science and Technology of Composites

Journal of Science and Technology of Composites

Assessment of damage index of retrofitted RC frame by using CFRP under cyclic loading

Document Type : Research Paper

Authors
Shohreh Alaedini 1
Mohammad-Zaman Kabir 2
1 Department of civil Engineering, Amirkabir University of Technology, Tehran, Iran.
2 Department of civil Engineering, Amirkabir University of technology, Tehran, Iran .
Abstract
Current study investigates the seismic performance of the reinforced concrete (RC) portal frames with Cyclic loading, emphasizing on the failure at the beam-column junction. Fiber reinforced polymer (FRP) is excessively FRP, used to restore RC flexural components as beam and columns. Here, the main interest is to focus on Dissipated energy, the ductility and strength enhancement of CFRP retrofitted shear-critical parts of the RC frame under a Ductility successively lateral cyclic loading. Two types of FRP strengthening schemes, U shaped Wrap (UW) and L shaped Wrap (LW), are used as external bonded sheets. Numerical simulation is conducted using LS-DYNA FE software and Seismostruct software. Moreover, the results in terms of load displacement are validated with the experimental data. The crack pattern at the critical region, connection area, due to the shear deficient strength is studied in details for both control and retrofitted specimens. In a conducted parametric study, the optimum stacking sequence is obtained for a better performance of the RC frame subjected to the lateral cyclic loading. In this direction, the overall energy dissipation and overall ductility assessment are calculated.
Keywords
RC frame
Cyclic loading
FRP
Dissipated energy
Ductility
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Balsamo, A., Colombo, A., Manfredi, G., Negro, P., Prota, A. (2005). Seismic behavior of a full-scale RC frame repaired using CFRP laminates. Engineering Structures. 27, 769-780 Duong, K., Sheikh, A., and Vecchio, F. (2007). Seismic Behavior of Shear-Critical Reinforced Concrete Frame: Experimental Investigation. ACI Structural Journal. 104 (3)