Title:
Horizontal Shear Capacity of Composite T-Beams Reinforced with Glass Fiber-Reinforced Polymer Interface Shear Reinforcement
Author(s):
Moataz Mahmoud, Mohamed Eladawy, Basil Ibrahim, and Brahim Benmokrane
Publication:
Structural Journal
Volume:
121
Issue:
4
Appears on pages(s):
225-236
Keywords:
analytical equations; composite reinforced concrete T-beam; crack pattern; design codes; glass fiber-reinforced polymer (GFRP) bars; interface shear stress; reinforced concrete; shear reinforcement and connectors; shear stress and slip
DOI:
10.14359/51740718
Date:
7/1/2024
Abstract:
Composite construction has proven to be cost-effective, as this
method merges precast and cast-in-place elements while preserving
the effectiveness and seamless nature of monolithic construction.
There are no experimental research results on the behavior of glass
fiber-reinforced polymer (GFRP)-reinforced composite beams in
the case of horizontal shear transfer in composite T-beams. This
research aims to investigate a novel and sustainable approach
using noncorroding GFRP as shear-transfer reinforcement in
composite reinforced concrete (RC) T-beams. A total of six fullscale
RC T-beams (one monolithic RC beam and five composite RC
beams) measuring 4200 mm (165.4 in.) in length, 420 mm (16.5 in.)
in depth, and 250 mm (9.8 in.) in width were constructed and tested
until failure. The main experimental variables evaluated were shear
reinforcement type (GFRP or steel stirrups); ratio (0.32, 0.35, or
0.48%), and shape (stirrups or bent bars). The test results were
analyzed in terms of ultimate horizontal shear stress, deflection,
slippage, and reinforcement strain. The experimental results indicate that the GFRP shear reinforcement provided adequate shear transfer capacities compared to steel when provided across rough concrete interfaces. Moreover, the test results show that increasing the shear reinforcement ratio enhanced the performance of the composite RC T-beams in terms of horizontal shear capacity and slip. Furthermore, the available equations specified in design
provisions, such as CAN/CSA S6-19 (2019) and AASHTO LRFD
(2018), exhibited unduly conservative predictions of the interface
shear strength of the GFRP bars. The results of this study unequivocally establish the viability and promise of employing GFRP bars as shear connectors in composite T-beam applications.