Repair of post-heated short rectangular reinforced concrete columns with FRP jackets

Abstract

The residual strength and stiffness of concrete columns are decreased when exposed to elevated temperatures. This study proposes an external confinement provided by fiber-reinforced polymer (FRP) to rehabilitate deficiencies of concrete columns that originate from fire damage. Recent studies show that the efficiency of this strategy is a function of column cross-section geometry and the number of FRP sheet layers applied. The current study investigates the repair of post-heated short rectangular RC (SRRC) columns with FRP jackets. Rectangular heat-damaged columns are wrapped with one or two layers of carbon FRP (CFRP) and glass FRP (GFRP). The experimental results indicate that the ultimate axial load capacity of post-heated columns, repaired with two layers of FRP was improved to a considerable level of the axial load capacity of the unheated columns. Moreover, it was found that the pseudo-ductility and energy dissipation capacity of the post-heated columns wrapped with two layers of CFRP jackets are larger than those of the unheated columns.