Shear Strength of High-Strength Concrete Members
N. Sakaguchi, K. Yamanobe. Y. Kitada, T. Kawachi, and S. Koda
Appears on pages(s):
beams (supports); columns (supports); cracking (fracturing); diagonal tension; high-strength concretes; high-strength steels; research; reinforced concrete; shear strength; shear tests; span-depth ratio; structural design; Structural Research
An equation is proposed for predicting the ultimate shear capacity of reinforced concrete columns and beams composed of high-strength concrete having a compressive strength of up to 90 MPa, and high-strength reinforcing bars having a tensile strength of 1000 MPa. Six beams and ten columns with and without shear reinforcement were tested to determine their diagonal cracking strengths and ultimate shear capacities. The shear span-depth ratio was 1.0 for the beams and 1.14 for the columns. The quantity pw åy (pw: shear reinforcement ratio; åy: yield strength of shear reinforcement) was varied from 0 to 11.2 MPa. The axial stress in the columns was varied at 0, 18.4, and 36.8 MPa. The current ACI Building Code equation for predicting shear capacity of deep beams was found to be applicable to the beams fabricated with high-strength concrete. However, it cannot be applied to the members with high axial load stress. The equation proposed in this paper accurately predicts the ultimate shear capacity of reinforced concrete columns as well as the beams made with high-strength concrete and high-strength steel bars.