TECHNICAL PAPER
Shear and flexural strengthening of deficient flat slabs with post-installed bolts and CFRP composites bonded through EBR and EBROG
Ala Torabian,
Brisid Isufi,
Davood Mostofinejad,
António Pinho Ramos,
Corresponding Author
Ala Torabian
Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, Iran
Correspondence
Ala Torabian, Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, Iran.
Email: [email protected]
Search for more papers by this authorBrisid Isufi
Department of Civil Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
Search for more papers by this authorDavood Mostofinejad
Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, Iran
Search for more papers by this authorAntónio Pinho Ramos
Department of Civil Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
CERIS, Lisbon, Portugal
Search for more papers by this authorAla Torabian,
Brisid Isufi,
Davood Mostofinejad,
António Pinho Ramos,
Corresponding Author
Ala Torabian
Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, Iran
Correspondence
Ala Torabian, Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, Iran.
Email: [email protected]
Search for more papers by this authorBrisid Isufi
Department of Civil Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
Search for more papers by this authorDavood Mostofinejad
Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, Iran
Search for more papers by this authorAntónio Pinho Ramos
Department of Civil Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
CERIS, Lisbon, Portugal
Search for more papers by this authorDiscussion on this paper must be submitted within two months of the print publication. The discussion will then be published in print, along with the authors’ closure, if any, approximately nine months after the print publication.
Abstract
Fiber reinforced polymer (FRP) composites can be efficient for flexural strengthening of flat slabs if debonding of the FRP is postponed. However, with the increase of the flexural capacity, the flat slab becomes more susceptible to punching shear failure. In this context, four flexural or simultaneous flexural and punching shear retrofitting systems are investigated in this study to strengthen a flexure-deficient flat slab. Externally Bonded Reinforcement on Grooves (EBROG) and externally bonded reinforcement (EBR) methods are used for flexural strengthening in two cases: slabs without punching shear reinforcement and with post-installed shear bolts as shear reinforcement. According to the results, flexural strengthening of the slab using the EBR and EBROG techniques increased its load capacity by 12% and 21%, respectively. Simultaneous flexural and shear strengthening of the slab using the EBROG technique was the most effective, leading to a 57% enhancement of the load capacity. For specimens whose failure was governed by punching, comparing the results with code predictions showed that Eurocode and ACI (and the respective guide documents fib bulletin 90 and ACI 440.2R) overestimated the capacity of these specimens. In cases where failure was governed by flexure, a simple application of the yield line theory predicted reasonably well the load capacity of the specimens.
CONFLICT OF INTEREST
The authors declare that there is no conflict of interest.
Open Research
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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