The Proposal for Monolithic Coefficients for Reinforced Concrete Columns Strengthened by Partial Reinforced Concrete Jacketing

Abstract

Reinforced concrete (RC) jacketing is one of the most widely adopted methods for strengthening RC structures. Full jacketing is adopted in the case of interior columns and monolithic behaviour is easily ensured. However, in the case of corner and edge columns, partial reinforced concrete jacketing should be considered. Partial jacketing also leads to a significant increase in stiffness and resistance, but monolithic behaviour is not achieved. For this reason, and in order to provide guidance for design, it is necessary to consider monolithic coefficients. The monolithic coefficient (K) is the relationship between the behaviour of the jacketed reinforced concrete element and the behaviour of an equivalent monolithic element, i.e. with the same geometry and materials. The value of K is unity for monolithic behaviour and less than 1 otherwise. To obtain a K value close to 1, it is necessary to ensure good adhesion between the jacketing and the original column. The main aim of the PhD thesis presented here is to propose K values for different design cases. The proposals will be based on numerical studies, validated with experimental tests and sensitivity analyses. The proposals will be compared with the K values proposed by EC 2 & 8-3, fib MC 2010 & 103, and ACI 318. Numerical models and experimental tests on columns strengthened by partial jacketing will analyse multiple parameters such as cracking, deformation and resistance.