Effect of FRP Strips Configuration, Beam Dimensions and Amount of Tensile Rebars on Shear Capacity of Reinforced Concrete Beams

Document Type : Research Article


1 Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran

2 Dept of Civil Engineering/Islamic Azad University, Najafabad Branch


In this paper, the effect of the distance, number of layers and cross-sectional area of FRP strips, the amount of longitudinal rebars, dimensions of beam and compressive strength of concrete on shear capacity of reinforced concrete beams with rectangular crosssection stiffened by FRP strips under symmetrical concentrated loads using the finite element method has been studied. For this reason, the non-linear analysis of 101 reinforced beams has been performed for evaluation of the effect of the parameters on load capacity and mid-span deflection of the beams with and without strengthening. Obtained results indicate that for a constant concrete compressive strength, increasing the width and the number of layers of FRP strips increases the load capacity compared to the control beam. By changing the layout of reinforcing strips with irregular intervals along the beam, the load capacity increase is about 6% to 35%. Also, the increase of the amount of longitudinal rebars from Φ10 to Φ14 creasing the compressive strength of the concrete from 30 MPa to 50 MPa, and increasing the cross-sectional area of the beam from 150 × 300 mm to 150 × 400 mm in unstiffened beams, increase the load capacity by 31%, 23% and 55%, respectively.


Main Subjects

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