Title:
Seismic Tests and Strength Models of Diaphragm-to-Wall Connections with Collector Reinforcement and Construction Joint
Author(s):
Tae-Sung Eom, Seung-Jae Lee, and Insung Kim
Publication:
Structural Journal
Volume:
123
Issue:
2
Appears on pages(s):
115-128
Keywords:
connection; diaphragm; shear friction; slab-to-wall connection; strut-and-tie model
DOI:
10.14359/51749304
Date:
3/1/2026
Abstract:
In this study, the behavior of diaphragm-to-wall connections with collector reinforcement and construction joints was investigated. Four slab-to-wall connection specimens were tested under cyclic loading. Diaphragm connection details, such as shear friction reinforcement (that is, slab dowel bars anchored by 90-degree hooks within the wall) and the use of spandrel beams as collectors, were considered as test variables. When fabricating the specimens, concrete was consecutively cast for the wall and slab, and construction joints were placed on the sides of the wall and spandrel beams. The tests showed that the diaphragm connections exhibited the typical ductile behavior characterized by the robust initial stiffness and subsequent post-yield plastic behavior. Before concrete failure on the front of the wall, the load transfer from the diaphragm to the wall was governed by a nodal zone action; then, the subsequent connection behavior was dominated by shear friction as sliding failure occurred on the side of the wall along the slab construction joints. The diaphragm-to-wall connection strengths were evaluated using the strut-and-tie model and shear friction theory. The calculated strengths were in good agreement with the test strengths. Based on the investigation results, design considerations of the diaphragm-to-wall connection were proposed.
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