Title:
Shear Strength of Non-Slender Reinforced Concrete Beams
Author(s):
Jesús-Miguel Bairán, Raul Menduiña, Antonio Marí, and Antoni Cladera
Publication:
Structural Journal
Volume:
117
Issue:
2
Appears on pages(s):
277-289
Keywords:
deep beams; loads near supports; non-slender beams; reinforced concrete; shear span; shear strength
DOI:
10.14359/51721369
Date:
3/1/2020
Abstract:
Shear strength of non-slender reinforced concrete beams, in which a/d ≤ 2.5, is enhanced due to arching action. Current shear design methods for such elements, including the strut-and-tie method (STM), show deviations with respect to tests results. In this paper, a shear strength mechanical model developed for slender beams is extended to non-slender beams. The effects of the non-planar strain distribution, of the multi-compression stress state generated near the applied load, and those of the pre-determined position and inclination of the critical shear crack are incorporated in the model formulation. The predictions of the proposed model have been compared with those obtained using the STM following the ACI and FIP recommendations and the EC2 simplified proposal. Three previously published databases, including the results of 486 shear tests of non-slender beams with and without web reinforcement, have been considered. The predictions by the proposed model resulted in better precision and less scatter, for all subsets of tests, while the proposed method is direct and simpler for daily engineering purposes.
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