Title:
Experimental Study on Restraining Headed Bars in Roof-Exterior Connection
Author(s):
Jang-Woon Baek and Thomas H.-K. Kang
Publication:
Structural Journal
Volume:
118
Issue:
6
Appears on pages(s):
251-265
Keywords:
concrete capacity design; concrete side-face blowout failure; headed bar; head-restraining bar; knee joint; prying action; roof-level exterior beam-column connection
DOI:
10.14359/51732851
Date:
11/1/2021
Abstract:
For roof-level exterior beam-column connections, the design requirement associated with side-face blowout failure for restraining headed bars can be alleviated by considering the concrete contribution. To evaluate concrete strength, investigation of the safety against side-face blowout failure of such knee-joint connections is deemed warranted. In this study, existing experimental tests for roof-exterior beam-column connections were reviewed and a cyclic loading test for a full-scale roof-exterior connection specimen was performed to examine concrete side-face blowout strength. In addition, the head-restraining bar area required in the current ACI 318 design provision and in the original ACI 349-97 design provision was evaluated. Results indicate that the head-restraining bar area required in ACI 349-97 was sufficient to
prevent concrete side-face blowout failure for both Type 1 and 2 specimens. For conservative design, an explicit equation was also proposed for design of head-restraining bars in roof-level exterior connections.
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