The effect of FRP characteristics on the behavior of square columns under eccentric loads

Document Type : Research Paper


Department of Civil Engineering, Sanandaj Branch, Islamic Azad University, Sanandaj, Iran


Modelling the stress-strain relationship of FRP confined concrete is of vital importance in predicting the structural behaviour of confined concrete columns. In recent years the axial stress-strain behaviour of confined concrete under concentric loading is well established, but the behaviour under eccentric loading when axial and bending loads are combined is not well understood. Adding FRP materials to upgrade deficiencies of structural components can save lives by preventing collapse, reducing the damage, and the need for their costly replacement. The retrofit with FRP materials with desirable properties provides an excellent replacement for traditional materials, such as steel jackets, to strengthen the reinforced concrete. Existing studies have shown that the use of FRP materials restores or improves the column's original design strength for possible axial, shear, or flexure and in some cases allows the structure to carry more load than it was designed for. This paper summarizes the results of a research program to study the fundamental stress-strain behaviour of concrete confined by various types of fibre-reinforced polymer (FRP) composite jackets. By using three different types of FRP sheets with different mechanical characteristics, it can be concluded that the e/d ratio in all cases has the most effect on the square column behaviour.


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Volume 14, Issue 3
March 2023
Pages 201-211
  • Receive Date: 10 July 2022
  • Revise Date: 14 August 2022
  • Accept Date: 03 September 2022