Abstract
This study concerns with flexural behavior of RC beams strengthened by carbon fiber reinforced polymer (CFRP) using finite element method (FEM). ABAQUS program has been used in this research. The load-deflection relationship, crack pattern, strain in the concrete at mid-span section of the beam and failure modes of all tested beams are studied. After validation of FEM model, parametric studies are presented to assess the effect of the compressive strength of concrete, thickness, and length of CFRP, and the presence of CFRP on stress in steel bars. From the current results, it can be obtained that the flexural capacity of RC beams strengthened with CFRP increased by 6.6% for beam strengthed by EBR and to 108.8% for beam strengthed by near surface mounted (NSM) compared to the reference beams. According to parametric studies, it is found that by increasing the compressive strength of concrete from 30 MPa to 70 MPa, the beam capacity increase by 25.6%, while increasing the length of CFRP from 600 mm to 900 mm leads to increase the beam capacity by 12.7%. Increasing thickness of CFRP sheet from 0.11 mm to 0.5 mm leads to an increase in the stiffness and the flexural capacity of the beam by 47.9%. Also, the results of this study approved that the strengthening of RC beams by CFRP laminates using the NSM technique is more efficient than externally bonded reinforcement (EBR) techniques and this is agreed with the experimental results. Finally, it can be concluded that the finite element model provides good accuracy compared to the experimental results and ACI-440 results .
Highlights
Reinforced concrete structures usually have to face modification and improvement of their performance throughout their service life
He found that the beams strengthened with near surface mounted (NSM) laminate achieved a higher maximum load than those strengthened with externally bonded reinforcement (EBR) for a similar area of carbon fiber reinforced polymer (CFRP). (Hong et al, 2011) and (EI-Hacha and Rizkalla, 2004) found that the failure mode of RC beams strengthened by CFRP strips usually occurs due to CFRP strip rupture, accompanied by concrete compression failure
After validation of the finite element method (FEM) model, parametric studies are presented to assess the effect of the compressive strength of concrete, thickness, length of CFRP, and the presence of CFRP on the flexural strength of RC beams strengthened with CFRP
Summary
Reinforced concrete structures usually have to face modification and improvement of their performance throughout their service life. The most contributing factors are modification in their use, new design standards, deterioration because of corrosion in the steel caused by exposure to an aggressive environment and accident events like earthquakes. The improvement of the performance of RC members throughout their service life can do it by strengthening or retrofitting and repairing of the member. Using CFRP to strengthen RC beams is a common type of strengthening in the field of structural engineering (Obaidat, 2011); (Bodzak, 2019). The use of CFRP in strengthening RC beams has become an important alternative method and more effective than other methods such as strengthening by steel plate. CFRP has good mechanical properties such as high resistance to the corrosion, very high strength to density ratio, faster installation and reduced maintenance costs (Obaidat et al, 2010); (El Gamal et al, 2019)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
