Strengthening and Repair of Circular RC Slabs Using CFRP Strips

The main purpose of this study is to evaluate the effect of CFRP strips on the behavior of circular RC slabs which have different shapes of openings (circle, square, and rectangle). Twenty seven circular RC slabs were constructed and tested under repeated loading. The experimental variables considered in this study include the shape of openings, the position of openings, and the form of strengthening. All the slabs were geometrically similar with dimensions of (1200mm in diameter and 75mm in thickness) and the repeated loads were applied to the circular slabs through annular load subjected at the center of slabs. The experimental results indicated that the use of CFRP strips to upgrade the circular RC slabs with openings has significant effect on overall behavior such as the ultimate load, stiffness, ductility, and deflection. Depending on the CFRP strengthening scheme used, the ultimate load capacity increased by (27-52)%. In general, the role of CFRP strips in repairing circular slabs was found to be bigger than its role in strengthening circular slabs.