Static and Dynamic Behavior of Circularized Reinforced Concrete Columns Strengthened with Hybrid CFRP


  • Z. H. Abdulghafoor Department of Civil Engineering, University of Baghdad, Iraq
  • H. A. Al-Baghdadi Department of Civil Engineering, College of Engineering, University of Baghdad, Iraq
Volume: 12 | Issue: 5 | Pages: 9336-9341 | October 2022 |


In this study, three strengthening techniques, near-surface mounted NSM-CRFP, NSM-CFRP with externally bonding EB-CFRP, and hybrid CFRP with circularization were studied to increase the seismic performance of existing RC slender columns under lateral loads. Experimentally, 1:3 scale RC models were studied and subjected to both lateral static load and seismic excitation. In the dynamic test, a model was subjected to El Centro 1940 NS earthquake excitation by using a shaking table. According to the test results, the strengthening techniques showed a significant increase in load carrying capacity, of about 86.6%, and 46.6%, for circularization and NSM-CFRP respectively, of the reference unstrengthened columns. On the other hand, columns strengthened with hybrid NSM-CFRP and EB-CFRP showed a different failure mode. Dynamically, the lateral drift was decreased by about 75%, 47%, and 49% for earthquake amplitudes of 0.05g, 0.15g, and 0.32g respectively. Finally, it was concluded, depending on the static and dynamic analyses, that the circularization process showed a significant increase in lateral load-bearing capacity.


Circularization, strengthening, CFRP, NSM, dynamic, slender column


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How to Cite

Z. H. Abdulghafoor and H. A. Al-Baghdadi, “Static and Dynamic Behavior of Circularized Reinforced Concrete Columns Strengthened with Hybrid CFRP”, Eng. Technol. Appl. Sci. Res., vol. 12, no. 5, pp. 9336–9341, Oct. 2022.


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