Stress-strain model for high strength concrete confined with FRP

Ducti lity of High Strength Concrete (HSC) columns can be increased by lateral confinement. Theconventional confinement with steel reinforcement may not always be adequate to provide the ductility levels desired by the engineer. The lateral confinement by FRP can provide signifi cantly higher confinement stresses than the cOllventional steel reinforcement, and convenient for repair applications. Confining pressure applied by FRP is a functi on of the lateral stra in of concrete. Therefore information of axial stress, axial strain and lateral strain rel ationships of concrete is fundamental in the design of confinement. Many existing models are based on test results with low confining pressures which are not suitable for modelling FRP confined concrete. The authors present a model in this paper which is suitable for use in des igning FRP confinement of concrete. Model results arc compared with experiment al results ofFRP confined columns. The results demonstrate the model is suitable for this use,