Flexural Strengthening of Defected RC Slabs Using Strain-Hardening Cementitious Composites (SHCC): An Experimental Work

Using the strain-hardening cementitious composites (SHCC) in strengthening the structural members appeared in the last years, but strengthening the slabs using SHCC is very rare. This research presented experimentally the strengthening of RC slabs by using SHCC layers in the tension side. The main aim of this research is studying the flexural behavior of RC slabs strengthened using SHCC. The experimental program consisted of six identical RC slabs. All slabs had the same compression bars and were without tension bars. The width and depth of the slabs were 400 mm and 80 mm, respectively. The total length of the slabs was 1800 mm which was divided into a simple span and cantilever using intermediate support. The research focused on the layer thickness and the reinforcement ratio of the layer. The layer depth-to-the original slab depth ratios were 25%, 37.5% and 62.5%, while the reinforcement ratios of the layer were 1.25%, 1.88% and 2.51%. Overlaying the SHCC layer at the tensile face of the unreinforced slabs enhanced the first crack by 63.73–318.68% and the ultimate carrying load by 18.18–40.91%. Using the SHCC layer is adequate for the recommended ductility index according to FIB code.