Title:
Discrete Shear Strength of Two- and Seven-Circular-Hoop and Spiral Transverse Reinforcement
Author(s):
Yu-Chen Ou and Si-Huy Ngo
Publication:
Structural Journal
Volume:
113
Issue:
2
Appears on pages(s):
227-238
Keywords:
discrete computation; integral averaging method; multi-circularhoop transverse reinforcement; multi-spiral transverse reinforcement; shear reinforcement
DOI:
10.14359/51688058
Date:
3/1/2016
Abstract:
This study developed discrete computational shear strength (DCSS) models for two-circular-hoop, two-spiral, seven-circular-hoop, and seven-spiral transverse reinforcement for reinforced concrete columns. The DCSS models show that as a shear crack moves along the column, the reinforcement shear strength varies periodically. The critical shear crack, which yields the smallest shear strength, can be from any of the shear cracks that intercept at least one edge of a hoop series or spiral. The conditions are presented for when a shear crack intercepts the two edges of every hoop series or spiral, which leads to a drastic reduction in shear strength. At the critical shear crack condition, the DCSS models yield shear strength lower than the integral averaging method. To control the error of the integral averaging method, the ratio of the reinforcement spacing to hoop or spiral diameter should be limited. Charts to correct the error are presented for use in practice.
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