Title:
Behavior of Monotonically Loaded Slab-Column Connections Reinforced with Shear Studs
Author(s):
Thai X. Dam, James K. Wight, and Gustavo J. Parra-Montesinos
Publication:
Structural Journal
Volume:
114
Issue:
1
Appears on pages(s):
221-232
Keywords:
punching shear; shear reinforcement layout; shear studs; two-way slab
DOI:
10.14359/51689165
Date:
1/1/2017
Abstract:
A total of five full-scale interior slab-column connections were tested under concentric monotonically increased loading. The slabs were 10 ft (3050 mm) square and 10 in. (254 mm) thick, and columns were 12 x 12 in. (305 x 305 mm). The specimens were built with Grade 60 reinforcement and 4000 psi (27.6 MPa) normal-weight concrete. Slab flexural tension reinforcement ratios were 0.87% in three specimens and 1.25% in the other two. One specimen with a slab reinforcement ratio of 0.87% was built without shear reinforcement. The other specimens were reinforced with headed shear studs. The studs were placed in either a radial or an orthogonal layout. Test results show that shear strength equations in the ACI Building Code overestimated the strength of the slab-column connections with a 0.87% slab flexural reinforcement ratio. Also, significant differences in failure mode were observed between slab-column connections with shear studs arranged in a radial layout and those with an orthogonal stud arrangement. Recommendations to improve shear strength of slab-column connections are presented.
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