Title: Maximum Shear Strength of Reinforced Concrete Beams

Author(s): Shyh-Jiann Hwang, Yu-Hsuan Yang, and Yi-An Li

Publication: Structural Journal

Volume: 119

Issue: 2

Appears on pages(s): 19-30

Keywords: force-transfer mechanism; maximum shear strength; shear failure

DOI: 10.14359/51734375

Date: 3/1/2022

Abstract:
Current codes limit the maximum shear strength in reinforced concrete beams to prevent possible sudden shear failure due to over-reinforcement. The ACI 318-19 limit is criticized to be over-conservative, especially for high-strength concrete beams. Based on the force-transfer mechanism of the beams, this paper investigates this issue by deriving a model to determine the shear strength of rectangular beams with a shear span-depth ratio exceeding 2. According to the proposed model, it is found that there are two influential parameters of the maximum shear strength for beams—that is, concrete strength and longitudinal tension reinforcement. Considering the softening phenomenon of reinforced concrete, the use of √fcꞌ in the ACI 318-19 limiting equation seems appropriate for high-strength concrete beams. However, the ACI 318-19 limit on the maximum shear strength of beams seems conservative for beams with a larger amount of longitudinal tension reinforcement.