H. R. Salehian - Lecturer of Civil Engineering Dept., Islamic Azad University, Semnan Branch, Semnan, Iran
A. Kheyroddin - Associate Professor, Civil Engineering Faculty, Semnan University, Semnan, Iran

In recent years, the use of FRP jackets for strengthening of weak concrete columns has become increasingly popular. The confinement effect of the externally bonded FRP systems in rectangular and square sections of concrete columns is known to be complicated and less than those in circular sections. In this article, the predictive design equations for calculating the compressive strength of FRP-confined concrete columns in three current international guidelines and five theoretical models have been introduced and effective parameters in each of them have been investigated. For a comparative study, also, a database consists of experimental results of 43 prismatic specimens of different cross-sectional shapes and confinement details have been collected. The analytical results show that the section’s shape and dimensions are effective parameters in diversity of experimental and theoretical results. Also, by defining the effective actors, a model has been expanded for prismatic FRP-confined concrete columns. Based on the analytical results, the expanded model indicates acceptable predictions in comparison with the other models and guidelines.

FRP, concrete column, confinement, shape factor, compressive strength