Title:
Punching Shear Tests of Slabs with High-Strength Continuous Hoop Reinforcement
Author(s):
Tae-Sung Eom, Su-Min Kang, Tae-Woo Choi, and Hong-Gun Park
Publication:
Structural Journal
Volume:
115
Issue:
5
Appears on pages(s):
1295-1305
Keywords:
continuous hoop; footing; punching shear; shear reinforcement; slab; stirrup
DOI:
10.14359/51702231
Date:
9/1/2018
Abstract:
The punching shear strength of reinforced concrete (RC) slabs with high-strength (Grade 70 ksi [500 MPa] equivalent) continuous hoop shear reinforcement is investigated. Preassembled continuous hoops are used as the shear reinforcement of slabs without engaging in flexural reinforcement. Through punching-shear tests of eight slab specimens, shear strength and failure mode are investigated. Test results show that the continuous hoops successfully increase the shear strength of slabs, provided that anchorage detail is appropriate to ensure yielding of the shear reinforcement. The shearresisting mechanism in slabs differs depending on the amount of shear reinforcement. In lightly reinforced slabs, the maximum strength occurs early, before yielding of shear reinforcement. On the other hand, in slabs with more shear reinforcement, the maximum strength occurs at a large deflection where the shear reinforcements yield. Based on these results, two strength criteria for punching shear
depending on the amount of shear reinforcement are proposed.
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