Title:
Strengthening of Two-Way Slabs Using Steel Plates
Author(s):
U. Ebead and H. Marzouk
Publication:
Structural Journal
Volume:
99
Issue:
1
Appears on pages(s):
23-31
Keywords:
concrete; punching shear; reinforcement; repair.
DOI:
10.14359/11032
Date:
1/1/2002
Abstract:
This paper introduces a strengthening technique of two-way slabs using steel plates and steel bolts. The effectiveness of two configurations of steel plates and four different arrangements of steel bolts were evaluated. The strengthening steel plates were extended to twice the slab depth around the column and acted as a drop panel of an equivalent concrete depth. Steel bolts were used as vertical shear reinforcement. Eight bolts were sufficient to transfer the horizontal forces from the steel plates to the concrete and the confining concrete sandwiched between the steel plates. The strengthened slabs showed an increase in stiffness and energy absorption. In addition, the ductility was slightly improved. The load-carrying capacity of the strengthened slabs was increased by 56.55, 57.76, and 64.56% over that of the control specimen with slabs that had eight, 12, and 16 bolts, respectively. The research presents a strengthening concept that can be used to strengthen two-way slabs in multistory structures. A simple approach that was based on the yield line theory showed good agreement with test results.