Strengthening of Interior Slab–Column Connections Using a Combination of FRP Sheets and Steel Bolts
Publication: Journal of Composites for Construction
Volume 10, Issue 5
Abstract
The results of an experimental investigation undertaken to evaluate a new technique for strengthening interior slab–column connection in combined flexural and shear modes are presented. The technique consists of using a combination of shear bolts inserted into holes and prestressed against the concrete surface for improving the punching shear capacity, and external [fiber-reinforced polymer (FRP)] reinforcement bonded to the tension face of the slabs in two perpendicular directions for increasing the flexural strength of the slabs. Square slab specimens of dimensions were tested and the main test variables included the ratio of steel reinforcement (1.0 and 1.5%), span–depth ratio or thickness (55 and ) of the slabs, area, and configuration of steel bolts, and area of FRP reinforcement. It was found that the use of shear bolts alone improves the punching shear strength and increases the ductility of failure by changing the failure mode from punching to flexural. However, the use of a combination of shear bolts and a moderate amount of FRP reinforcement increased the flexural strength and resulted in a substantial improvement of the punching shear capacity of the slabs. The corresponding increases attained levels between 34 and 77%. A design approach is presented for evaluating the ultimate capacity of the slab–column connections when strengthened using the proposed strengthening technique. Strength results predicted by the proposed approach were in good agreement with the experimental results.
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Acknowledgments
This research was supported by the University Research Board at the American University of Beirut (AUB). The writers are most grateful for that support and to the Faculty of Engineering and Architecture at AUB for providing the testing and computing facilities.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 10 • Issue 5 • October 2006
Pages: 399 - 409
Copyright
© 2006 ASCE.
History
Received: Dec 2, 2004
Accepted: Nov 9, 2005
Published online: Oct 1, 2006
Published in print: Oct 2006
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