Title:
Development Length of Standard Hooked Bar Based on Non-Uniform Bond Stress Distribution
Author(s):
Hyeon-Jong Hwang, Hong-Gun Park, and Wei-Jian Yi
Publication:
Structural Journal
Volume:
114
Issue:
6
Appears on pages(s):
1637-1648
Keywords:
bearing force; bond strength; bond test; development length; hooked bar
DOI:
10.14359/51700918
Date:
11/1/2017
Abstract:
In this study, a design equation for the development length of hooked reinforcing bars was developed theoretically considering the effects of bond stress distribution and hook anchorage. A non-uniform bond stress distribution model with the hook anchorage effect was proposed, from which a design equation was derived. The proposed method was applied to 493 existing test specimens to predict the development length or the average bond stress of the reinforcing bars. The predicted results were compared with the existing test results and the predictions of current design codes including ACI 318, Eurocode 2, and Model Code 2010. The results showed that the proposed model predicted the test results with reasonable precision (average ratio of the test results to predictions = 1.17, and coefficient of variation = 0.196).
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