Retrofitting of Distressed RC Structures Using Near Surface Mounted Reinforcement

Abstract

AbstractDamage takes place in reinforced concrete structures due to, earthquakes, erroneous design, overloading, corrosion of reinforcement and due to ageing. Damaged reinforced concrete (RC) structural elements (beams, columns, slabs, etc.) can be retrofitted to enhance their load carrying capacity. Non-destructive testing methods are adopted for assessing the extent and degree of damage that has taken place in distressed RC structural elements. Retrofitting of damaged structural elements can be carried out only when the damage that has taken place is within repairable limits. The different types of retrofitting that can be adopted to restore damaged RC structural elements are: reinforced concrete jacketing, FRP wrapping (CFRP/GFRP), epoxy injection to seal cracks, near surface mounted reinforcement and external prestressing. In this particular work, a numerical study is carried out on retrofitting of structural elements, adopting near surface mounted reinforcement using CFRP rods to restore structural elements (beams/columns) that is present in a distressed RC structure that has undergone degradation at the material level on account of ageing. With the application of near surface mounted reinforcement the performance of the distressed structural elements present in the structure is assessed in terms of, increased stiffness and improved resistance towards deflection when such the structure is subjected to any future loading such as an earthquake. A numerical analysis is carried out on the retrofitted structure subjected to earthquake loading to study its performance and assess the efficacy of the retrofit using near surface mounted reinforcement. It was observed by carrying out the analysis of the retrofitted structure, the stiffness of the RC structural elements was observed to have improved that resulted in lower values of displacements.KeywordsReinforced concrete structuresDistress due to ageingRetrofitting using near surface mounted reinforcementCFRP rodsEarthquake loads