Title: Punching failure of slab-column connections reinforced with headed shear studs

Author(s): Thai X. Dam, James K. Wight, Gustavo J. Parra-Montesinos, Alex DaCosta

Publication: Symposium Paper

Volume: 315

Issue:

Appears on pages(s): 353-378

Keywords: Punching shear, slab reinforcement ratio, two-way slab, shear studs, shear reinforcement layout, integrity reinforcement

DOI:

Date: 4/1/2017

Abstract:
Seventeen large-scale interior reinforced concrete slab-column connections were tested to study the effect of different shear stud layouts and the percentage of slab flexural reinforcement. They were divided into two series M (twelve specimens) and S (five specimens) based on their dimensions. Each specimen in Series M had a 6 ft by 6 ft (1830 mm by 1830 mm) and 8 in. (200 mm) thick slab and a 6 in. by 6 in. (150 mm by 150 mm) column cross-section, while each specimen in Series S had a 10 ft by 10 ft (3050 mm by 3050 mm) and 10 in. (250 mm) thick slab and a 12 in. by 12 in. (300 mm by 300 mm) column cross-section. The percentage of slab flexural tension reinforcement was approximately either 0.8% or 1.2%, and shear studs were arranged in either an orthogonal or radial layout. Test results showed that shear strength equations in the ACI Building Code (ACI 318, 2014) overestimated the strength of some test specimens. Also, specimens with a radial layout of shear studs typically had higher strength and more ductile behavior than specimens with an orthogonal stud layout. Recommendations to improve the design of flat plate systems are presented.