Improving ductility and shear capacity of reinforced concrete columns with carbon fiber reinforced polymer

Özcan, Okan
The performance of reinforced concrete (RC) columns during recent earthquakes has clearly demonstrated the possible failures associated with inadequate confining reinforcement. The confinement reinforcement requirements of older codes were less stringent than present standards. Many studies were conducted by applying different retrofitting techniques for RC columns that have inadequate confinement reinforcement. A new retrofitting technique by means of Carbon Fiber Reinforced Polymer (CFRP) was developed and tested in many countries in the last decade. This technique is performed by CFRP wrapping the critical region of columns. The effectiveness of CFRP retrofitting technique was shown in many studies conducted worldwide. In Turkey, the frame members are considerably deficient from the seismic detailing point of view. Therefore, in order to use the CFRP retrofitting technique effectively in Turkey, experimental evidence is needed. This study investigates the performance of CFRP retrofitted RC columns with deficient confining steel and low concrete strength. It was concluded by experimental and analytical results that the CFRP retrofitting method can be implemented to seismically deficient columns. Moreover, two design approaches were proposed for CFRP retrofit design of columns considering safe design regulations.


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Improving seismic performance of deficient reinforced concrete columns using carbon fiber-reinforced polymers
ÖZCAN, OKAN; Binici, Barış; Ozcebe, Guney (Elsevier BV, 2008-06-01)
Reinforced concrete columns lacking transverse reinforcing steel do not possess necessary ductility to dissipate seismic energy during a major earthquake. The study reported herein investigates the use of carbon fiber-reinforced polymer (CFRP) wrapping as a method of retrofitting nonductile square reinforced concrete columns with low strength concrete and plain bars. Five specimens representative of transverse steel deficient flexure dominated columns in existing buildings were tested under lateral cyclic d...
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Citation Formats
O. Özcan, “Improving ductility and shear capacity of reinforced concrete columns with carbon fiber reinforced polymer,” Ph.D. - Doctoral Program, Middle East Technical University, 2009.