Shear-Flexure Interaction of r.c. Circular Columns Strengthened with FRP Seets

A new physical model for evaluation of N-M-V interaction resistance domain for concrete columns strengthened with FRP sheets is presented. The model provides a simple and efficient method for performance evaluation of strengthening action, and it can be used as a preliminary tool in retrofitting design of reinforced concrete circular columns. In order to point out the flexibility of the proposed method in evaluation of the resistance domain of R.C. elements strengthened with different FRP configurations, and to discuss the influence of N-M-V interaction, the resistance domain for a R.C. circular cross column, strengthened by several different layout arrangements of FRP reinforcements, is presented.