Nonlinear Modeling of Rectangular Reinforced Concrete Columns Jacketed Using FRP Materials

A database of 74 tests conducted on rectangular concrete columns retrofitted using externally bonded FRP jackets was used to evaluate leading methods for estimating strength and deformation capacities of FRP‐jacketed columns. Due to observed shortcomings in current methods, new relations for nonlinear modeling parameters (MPs) are proposed for FRP‐jacketed concrete columns. MPs include both deformation capacity and moment strength that account for the beneficial confining effects of FRP jackets. Parameters are provided in a format that facilitates evaluation of FRP‐jacketed columns within the ASCE/SEI 41 and ACI 369.1 frameworks. The proposed MP are intended for use in retrofit scenarios in which undesirable nonductile modes of strength degradation are precluded by the retrofit, such that retrofitted column behavior is governed by flexure. Anchorage of FRP composites for enhanced confinement and force transfer is treated explicitly in the proposed MP.