EXPERIMENTAL AND NUMERICAL ANALYSIS OF REINFORCED CONCRETE BEAM STRENGTHENED USING CARBON FIBER REINFORCED PLASTIC SHEETS AND BOLTED STEEL PLATE

Abstract

This paper presents experimental and numerical study on reinforced concrete (RC) beams with flexural strengthening by carbon fiber reinforced polymer (CFRP) sheets and steel plates. In the study, effect of strengthening on flexural of RC beams is examined. Also, the differences between CFRP sheet and steel plate retrofitting regarding flexural strength of the RC beams are indicated. For experimental study, seven RC beams were produced. One of the beams is regarded as “control sample”, three of samples were strengthened using CFRP sheets and the other three samples strengthened using steel plates. Four points bending test was conducted, vertical displacements of the beams were measured. Tests results indicated that the beams were strengthened for flexure became vulnerable shear failure and CFRP application was better strength values in flexure than steel plates application. For numerical analysis, three-dimensional finite element modeling of strengthened and non-strengthened reinforced concrete beams is prepared. Reinforced concrete beam is modeled by using hexahedral, steel plate and CFRP sheets are modeled by using tetrahedral elements. Finite element analysis is performed by using ATENA non-linear analysis program. The results of experiments and finite element analysis are compared. Results indicated that the strengthened reinforced concrete beams have larger moment capacity, yet exhibit shear failure. Although, strengthened samples exhibit shear failure, failure is not brittle. Experimental results are also validated by finite element analysis.

Keywords

• Reinforced concrete beams
• strengthening
• carbon fiber polymers
• steel plates

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