Investigation of the Influence of the Application Path of Confining Pressure: Tests on Actively Confined and FRP-Confined Concretes

Abstract

AbstractIt is often assumed that, at a given lateral strain, the axial compressive stress and strain of fiber reinforced polymer (FRP)–confined concrete are the same as those of the same concrete when it is actively confined under a confining pressure equal to that supplied by the FRP jacket. An experimental program was undertaken to assess the validity of this assumption, in which 63 actively confined and FRP-confined normal-strength (NSC) and high-strength concrete (HSC) specimens were tested under axial compression. The axial stress-strain and lateral strain-axial strain curves obtained from the two different confinement systems were assessed. The results indicate that, at a given axial strain, lateral strains of actively confined and FRP-confined concretes correspond when they are subjected to the same lateral confining pressure. At the points of intersection on the lateral strain-axial strain curves, FRP-confined NSC exhibits only slightly lower axial compressive stresses compared with those of activ...