NUMERICAL ANALYSIS OF REINFORCED CONCRETE BEAM COLUMN JOINT RETROFITTED USING CARBON FIBER REINFORCED POLYMER (CFRP) SHEETS

Abstract

The beam column joint is the critical zone in a reinforced cement concrete (RCC) moment resisting frame. It is subjected to large forces during severe ground shaking and its behavior has a significant influence on the response of a structure. Improper design and detailing of joint will result in brittle failures. To avoid such failures and meet specific beam column joint requirements, existing reinforced concrete structures must be strengthened. Retrofitting and strengthening are the most sustainable methods for improving the performance of reinforced concrete frame buildings. There are several methods for retrofitting beam column joints, the most common of which is Carbon Fiber Reinforced Polymer (CFRP). CFRP is a popular material for retrofitting due to its superior properties such as high corrosion resistance, high strength, high stiffness, and good resistance to chemical attack etc. Thus, it is important to examine more about retrofitting using carbon fiber reinforced polymer. This thesis paper is set out to study and provide insights about what is retrofitting, importance of retrofitting a beam column joint, and effectiveness of using of CFRP as a retrofitting agent for beam column joint based on numerical analysis. In this study, reinforced beam column joint retrofitted using CFRP is considered. Numerical investigation is done on normal beam column joint and CFRP retrofitted beam column joint. The numerical investigation is done using ABAQUS software. This study focuses on the influence of the orientation and number of layers of CFRP sheet with different fiber orientation on the performance of retrofitted joint. The comparison of the performance of retrofitted joint models in terms of load carrying capacity, ductility, energy dissipation capacity and stiffness degradation were also studied.