Comparison of methods for evaluation the resistance of slender columns strengthened with CFRP strips

This paper focuses on strengthening slender columns using CFRP (Carbon-Fibre Reinforced Polymer) strips, emphasizing the inclusion of their contribution to the overall resistance. For slender columns, second-order effects must be considered. Eurocodes EC2-04 and EC2-23 outlines three methods for calculating such effects: two simplified methods and a general method. Calculations of the column's load-bearing capacity have been performed using simplified methods, modified to account for the effects of strengthening with CFRP. Additionally, calculations using the general method were carried out with a computational algorithm written in Excel. The results of these calculations are compared with the outcomes of experimental strengthening tests on columns as well as with a numerical model created using the ATENA software.