CFRP Application in Retrofitting of R.C.C Beam

Abstract

Deterioration in reinforced concrete structures is a major issue faced by the infrastructures industries all over the world. Since complete replacement of these structures requires high investment, strengthening has become the suitable solution to modify and improve the performance of the structures. The strengthening of RC beams using FRP composites has become a popular structural strengthening technique, due to the well-known advantages of FRP composites such as their high strength-to-weight ratio and excellent corrosion resistance. This study explores the result of an experimental investigation for enhancing the flexure capacity of reinforced concrete (RC) beams with flexure deficiencies, strengthened with Carbon Fiber Reinforced Polymer (CFRP) sheets. Total 18 numbers of specimens were casted. Out of this 9 specimens were tested for control beam and 9 were for deterioration in that three were tested with CFRP wrapping respectively. The geometry of all beams are 1200mm overall length, 1000mm effective length (bearing 100 mm each side), 100 mm width and 150 mm depth with constant reinforcement as per design. The dimensions of all beams are kept same throughout the experiment. Experiments are conducted to study the flexural capacity of RC rectangular beams with and without FRP using local available materials. For the experiment four point bending test was conducted. Deterioration of Concrete is done by using solutions of calcium chloride (CaCl2) with 3 molal ion concentrations. The experimental results demonstrated that the use of CFRP composite strips increases the flexure capacity of the beams significantly by preventing the debonding of CFRP sheets, so that the full strength of the CFRP sheets get utilized.