Title:
Shear Test on Concrete Corbels: ACI 318-19 Formulas Evaluation
Author(s):
Bing Han and Yuan Huang
Publication:
Structural Journal
Volume:
121
Issue:
3
Appears on pages(s):
3-14
Keywords:
concrete compressive strength; horizontal stirrups; reinforced concrete corbel; shear span-depth ratio; strut-and-tie method (STM)
DOI:
10.14359/51740455
Date:
5/1/2024
Abstract:
The reinforced concrete corbel is widely used in assembled concrete
structures as a convenient cantilever support member. In this paper, eight double-corbel specimens with the same design load capacity were obtained according to the strut-and-tie method (STM) in ACI 318-19. Corbels with different dimensional parameters were
produced by varying the concrete compressive strength or shear
span separately. The differences in actual bearing capacity and
mechanical performance among the corbels were then compared to
assess the accuracy and safety of the STM under the two variables.
In addition, as the horizontal stirrups are not taken into consideration in the nominal design capacity of the STM, three non-stirrup corbel specimens were designed to investigate the effect of stirrups on the load-bearing capacity under different shear span depth ratios. The results show that changing the concrete strength
or shear span significantly affects the actual bearing capacity of
the corbels, despite the design load capacity remaining constant.
Increased compressive strength of the concrete or decreased shear
span at the design stage results in a higher level of safety for
the STM. The larger the shear span-depth ratio, the greater the
strengthening effect of the stirrups on the corbels’ bearing capacity.
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