Title: Stress Limit for Shear Reinforcement of High-Strength Columns

Author(s): Yu-Chen Ou and Nguyen Van Bao Nguyen

Publication: Structural Journal

Volume: 119

Issue: 1

Appears on pages(s): 131-141

Keywords: axial compression; columns; cyclic loading; high-strength concrete; high-strength reinforcement; shear strength

DOI: 10.14359/51733002

Date: 1/1/2022

Abstract:
Ten shear-critical high-strength columns with a shear span to effective depth ratio of 2.5 were tested using lateral cyclic loading. Test results showed that the use of high-strength shear reinforcement with fyt of 854 to 867 MPa (123,860 to 125,750 psi) generally increased the shear strength of the column and decreased strength degradation after the peak applied shear. However, the increase of shear strength was lower than that calculated based on the fyt. This was likely due to the fact that most of the high-strength shear reinforcement did not yield at the peak applied shear. The new ACI 318-19 shear strength equations were examined using the test data from this research and others. The shear strength equations with the stress limit for shear reinforcement set equal to 600 MPa (87,000 psi) were found to be conservative for high-strength shear reinforcement and showed a safety level for high-strength shear reinforcement similar to normal-strength reinforcement.