Title:
Development Length of Compression Reinforcing Bar Based on Nonuniform Bond Stress Distribution
Author(s):
Hyeon-Jong Hwang, Hong-Gun Park, and Wei-Jian Yi
Publication:
Structural Journal
Volume:
115
Issue:
6
Appears on pages(s):
1695-1705
Keywords:
bond strength; bond test; compression bar; development length; end bearing force
DOI:
10.14359/51702382
Date:
11/1/2018
Abstract:
In current design codes, the effects of cover concrete thickness, transverse reinforcement, and end bearing force on the compression development length are not considered. As a result, in particular design conditions, the development length of compression bars can be longer than that of tension bars. In the present study, a design equation for the compression development length of reinforcing bars was derived considering non-uniform bond stress distribution and end bearing effect. The proposed method was applied to 170 existing test specimens to predict the development length or strength of spliced compression reinforcing bars. The predicted results were compared with existing test results and the predictions of current design codes, including ACI 318, Eurocode 2, and Model Code 2010. The results showed that the prediction of the proposed model was better than those of other design methods, showing the average ratio of the test results to bar stress predictions = 0.97 and COV = 0.122.
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