REVIEW OF CONFINEMENT MODELS FOR FRP WRAPPED REINFORCED CONCRETE COLUMNS

Fiber Reinforced Polymer (FRP) reinforcements have been used in different configurations using various techniques for strengthening and repairing existing concrete bridges to restore or increase their capacity. Externally bonded FRP reinforcements in the form of sheets, plates, strips and fabrics are becoming widely accepted and are currently the most commonly used techniques for flexural and shear strengthening of concrete girders and slabs to provide additional flexural and shear strength or for wrapping concrete columns to provide confinement. Commonly used FRP materials for confining concrete columns to increase their strength and ductility includes Carbon, Glass and Aramid FRP composites. Several investigators have studied the stress-strain characteristics of FRP confined concrete columns and proposed several models to predict the behavior, yet, not all models predict the complete stress-strain behavior accurately. This paper reviews four selected confinement models to predict the stress-strain behavior of CFRP, GFRP and AFRP wrapped circular columns and compares the results with experimental data available from the literature. The comparison includes the ultimate confinement compressive strength and the ultimate axial strain of concrete. The result of this investigation shows that the most appropriate model to predict the stress-strain behavior of FRP wrapped concrete columns is the model proposed by Wu et al., (2003).

کلیدواژه ها:

Fiber Reinforced Polymers ، confinement ، circular columns ، strength