Design-oriented models for concrete columns confined by steel-reinforced grout jackets

This paper investigates the axial stress-strain response of concrete confined with Steel-Reinforced Grout (SRG) jackets comprising of Ultra High Tensile Strength Steel (UHTSS) textiles embedded in an inorganic binder. Brittle, semi-ductile and ductile stress-strain response curves are identified according to the level of confinement stiffness provided by the SRG jackets. A comprehensive experimental database of 80 SRG-confined columns is developed and used to assess the influence of key design parameters. The results are then used to propose new design-oriented models to predict the strength and ultimate strain of SRG confined concrete columns by taking into account the confinement stiffness of the jackets.