Title:
Strengthening of Continuous Concrete Slab Strips Containing Cutouts
Author(s):
Tamer El-Maaddawy, Jafer Alshawa, and Bilal El-Ariss
Publication:
Structural Journal
Volume:
113
Issue:
6
Appears on pages(s):
1243-1252
Keywords:
composites; continuous; cutouts; near-surface-mounted; slabs; strengthening
DOI:
10.14359/51689027
Date:
11/1/2016
Abstract:
Test results of 11 continuous reinforced concrete slab strips are reported in this paper. Ten specimens had a through-thickness cutout in either the sagging or the hogging region whereas one specimen was solid to act as a benchmark. Eight of the specimens with cutouts were strengthened in flexure using near-surfacemounted (NSM) composite reinforcement. The strength reduction caused by the cutout was more pronounced when installed in the sagging regions rather than in the hogging region. The NSM composite reinforcement fully restored the original strength of all specimens with cutouts, except one slab where only 90% of the original strength was restored. The strength gain was more pronounced for the specimens strengthened in the deficient sagging region. Test results showed that strengthened reinforced concrete slab strips can feature appreciable moment redistribution between the sagging and hogging regions. The experimental study was supplemented by a simplified analytical approach that provided reasonable prediction for the load capacity of the tested slab strips.
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