Title:
A New Technique for the Seismic Retrofit of Slab-Column Connections
Author(s):
Dritan Topuzi, Maria Anna Polak, and Sriram Narasimhan
Publication:
Structural Journal
Volume:
114
Issue:
6
Appears on pages(s):
1471-1481
Keywords:
ductility; flat plate systems; flat slabs; punching shear; slabcolumn connections
DOI:
10.14359/51689500
Date:
11/1/2017
Abstract:
This paper describes an experimental investigation on the behavior of reinforced concrete slab-column connections retrofitted with a new type of shear reinforcement while subjected to a combination of constant gravity loading and increasing cyclic lateral drift. The testing program consisted of six specimens: five specimens retrofitted for punching shear with a combination of steel bolts and flexible washers and one unretrofitted control specimen. Washers of different flexibilities were used with the bolts to introduce a larger but limited opening of punching shear cracks. The results show that this type of shear reinforcement improves the lateral loaddeformation response of the connections, increasing the ductility without a commensurate increase in stiffness and strength. The lower joint stiffness results in lower shear forces transferred to the column, while the continuous opening and closing of cracks results in larger energy dissipation through friction within the crack interfaces.
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