Abstract:
Many factors in service life which may be natural or manmade, are affecting existing concrete building structures. Corrosion of bars, spalling and deterioration of concrete and earthquake affect its performance of resisting loads, which lead to failure. Hence to prevent it from sudden failure FRP is one of the best materials for strengthening. FRP provides high strength and lightweight, corrosion resistance, nonconductive and impact resistant properties.
This thesis has presented some literature review on failure behaviour of RC beam under shear strengthening. The scope of work has been identified based on the above review work. The commercial FEM software, ABAQUS-2017 has been used for the purpose of implementing the works.
The objectives of this study were to investigate the behaviour of retrofitted beams and to develop a finite element model for FRP strengthened beams having different varying design parameters. The finite element model has been verified with other experimental and analytic results. Finally, the influence of different parameters on the behaviour of the strengthened beams was investigated. In this model non-linear behaviour of concrete material has been studied.
A mesh convergence study has been conducted to choose suitable number of elements for getting accurate results. Then some parametric studies were conducted for different types of FRP, orientations of FRP, different lengths of FRP and percentage of tensile reinforcement taking into account the shear behaviour of RC beam. Different types of FRP such as CFRP, E-GFRP and BFRP have also been considered to see their effect on shear capacity of beam.
The variation of strength in terms of load and deflection has been studied in case of perfect bonding with single and composite layer of FRP. Tension damage failure of concrete was also studied.
The results showed that when the length of FRP increased the load capacity of the beam also increased due to shear strengthening. Increased CFRP stiffness increased the maximum load only up to a certain value of the stiffness, and there after the maximum load decreased
