Finite Element Analysis of RC Beams Retrofitted and Strengthened with CFRP

Abstract

This study aims to develop a finite element model for accurately predicting the behavior of RC beams retrofitted and strengthened with CFRP strips. Two types of CFRP layout are modelled, CFRP wraps at the bottom without any anchorage, and CFRP strips with CFRP wrap as anchorage. The developed numerical models are validated by experimentally testing RC beam models for four-point bending. The concrete damage plasticity model is used for introducing non-linearity in concrete. The non-linear tensile and compressive parameters are taken from the ABAQUS manual specifications. The interface between the CFRP and RC beam surface was replicated using a perfect bond between the two. The results show that the developed numerical model accurately predicts the strength of retrofitted and strengthened beams. Though numerical models show higher initial stiffnesses and cracking load, especially in the case of a retrofitted specimen, where the initial stiffness is as high as 75%.

Keywords

• finite element modelling, cfrp, retrofitting, strengthening, load-deflection behaviour