Title:
Detailing of Cutoff Flexural Reinforcement
Author(s):
Sung-Gul Hong, Namhee Kim Hong, and Eo-Jin Lee
Publication:
Structural Journal
Volume:
113
Issue:
5
Appears on pages(s):
895-906
Keywords:
anchorage failure; bar detailing; cutoff bars; development length; embedment length; flexural bond; inflection point; shear failure; simple supports
DOI:
10.14359/51689143
Date:
9/1/2016
Abstract:
Flexural bond failure and anchorage failure, which are combined with shear failure at simple supports or near cutoff points, are investigated for bar detailing of positive and negative moment reinforcement in terms of development length and additional embedment length beyond the point of zero moment. The flexural bond requirement for safe bar development and the shear reinforcement necessary for the anchorage forces of cutoff flexural reinforcement at critical sections are drawn by consideration of the bond strength along straight or hook bars and its additional embedment length beyond zero moment. The proposed design equations and failure mode diagrams lead to safe bar detailing of reinforced concrete beams with inherent discontinuities of flexural reinforcement.
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