Title:
Experimental Investigation of Dapped Ends with Diagonal Reinforcement
Author(s):
Chathura Rajapakse, Herve Degee, and Boyan Mihaylov
Publication:
Structural Journal
Volume:
121
Issue:
4
Appears on pages(s):
35-46
Keywords:
dapped-end connections; diagonal reinforcement layout; flexural failures; reentrant corner cracks; shear failures
DOI:
10.14359/51740710
Date:
7/1/2024
Abstract:
Reinforced concrete dapped-end connections are susceptible to
formation of inclined cracks at the reentrant corner under service
conditions. As these connections also work with high shear stresses,
they require a high amount of reinforcement to ensure sufficient
load-bearing capacity. To deepen the understanding of this
topic, an experimental campaign of eight large-scale dapped-end
connections featuring diagonal reinforcement is presented. These
specimens, which are among the largest available in the literature,
are similar in size to the dapped ends typically used in bridges. The
test series captures both flexural and shear failures of dapped ends.
The crack displacements, crack patterns, and elongation of main
reinforcement are reported, with 56 continuous measurements of
deformations. The test results of this study are used in conjunction
with a similar study on specimens with orthogonal reinforcement
to investigate the impact of reinforcement layout. For the same
amount of dapped-end reinforcement, specimens with diagonal
reinforcement are considerably stronger than the corresponding
connections with orthogonal reinforcement. For both reinforcement
layouts, the crack widths exceeded typical code provisions
under service conditions.
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