Title: New Shear Strengthening Technique for Concrete Slab-Column Connections

Author(s): Ehab F. El-Salakawy, Maria Anna Polak, and Khaled A. Soudki

Publication: Structural Journal

Volume: 100

Issue: 3

Appears on pages(s): 297-304

Keywords: column; concrete; punching shear; shear reinforcement; slab; strength

DOI: 10.14359/12604

Date: 5/1/2003

Abstract:
The study presents an experimental program that involved tests on full-scale reinforced concrete slab-column edge connections. The aim of the program was to test a new method for strengthening existing reinforced concrete slabs for punching shear. The new strengthening technique consists of shear bolts externally installed in holes drilled through the slab thickness. Different configurations of the shear bolts around the column were tested. Four slabs were strengthened and two slabs, used as control specimens, did not contain any shear reinforcement. Two of the tested slabs (one strengthened and one control) contained openings in the vicinity of the column. The dimensions of the slabs were 1540 x 1020 x 120 mm with square columns (250 x 250 mm). The openings, where present, were square (150 x 150 mm) and directly adjacent to the inner face of the column. The slabs were tested up to failure under monotonic vertical shear forces and unbalanced moments. The presence of shear bolts substantially increased the punching capacity and the ductility of the connections.