Title:
Effect of Openings on Punching Shear Behavior of Concrete Flat Plates Reinforced with GFRP Headed-End Bars (Prepublished)
Author(s):
Ibrahim A. Abdelwahed and Ehab F. El-Salakawy
Publication:
Structural Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
anchorage; edge connections; flat plates; glass fiber-reinforced polymers (GFRP); headed-end bars; openings; punching shear
DOI:
10.14359/51752023
Date:
8/26/2026
Abstract:
Openings in the vicinity of reinforced concrete (RC) slab-column connections exacerbate the susceptibility of flat plates to punching shear failure. Using Glass Fiber-Reinforced Polymer (GFRP) as flexural reinforcement may reduce punching resistance due to its low modulus of elasticity. However, GFRP headed-end bars offer greater stiffness, ease of installation, reliable anchorage, and less reinforcement congestion than bent bars. This study presents the results of five full-scale slab-column edge connections. The test parameters are the type of reinforcement (GFRP and steel), anchorage (bent and headed end), and the presence of slab openings in the vicinity of the column. All specimens exhibited sudden punching shear failure. Slabs reinforced with GFRP headed-end bars showed no evidence of anchorage failure. Openings significantly reduced punching capacity, with a similar percentage for both steel- and GFRP-RC slabs. Moreover, Canadian Standards and American codes highly underestimated the capacity of the specimens.