Design-Oriented Stress-Strain Model for FRP-Confined Concrete in Rectangular Columns

Abstract

The behavior of fiber reinforced polymer (FRP)-confined concrete in circular columns has been extensively studied, but much less is known about concrete in FRP-confined rectangular columns in which the concrete is nonuniformly confined and the effectiveness of confinement is much reduced. This paper presents a simple design-oriented stress-strain model for FRP-confined concrete in rectangular columns. To this end, existing theoretical models are first reviewed. A database of existing test results collected by the authors is next presented, which is then augmented by a new set of results from tests conducted by the authors. The augmented test database is next employed to assess the existing theoretical models. Finally, a stress-strain model is presented, which is an extension of a recent designoriented stress-strain model developed for concrete uniformly-confined with FRP based on test results of circular concrete specimens. The proposed stress-strain model is shown to provide satisfactory predictions of the stress-strain curves obtained from the authors' new tests.

Behavior of CFRP Confined Rc Columns Under Axial Load and Uniaxial Cyclic Lateral Loading

“…Several analytical models for the stress-strain relationship of FRP confined concrete subjected to axial compression have been developed in literature [11][12][13][14][15][16]. Two stress-strain models for FRP confined concrete [17,18] were also implemented in the open-source platform OpenSees [19].…”

Effect Of Pre-Tensioned Level on Axial Stress-Strain Behaviour of Confined Concrete: A Review

“…A hoop strain reduction factor was introduced in order to properly quantify the confining pressure and the stress-strain behaviour of FRP-confined concrete. The confining pressure that takes into the hoop strain reduction factor is named as the actual confining pressure by Lam and Teng [6]. However, it was found that the confining effect of this type of confinement requires a certain lateral dilation of concrete in order to be activated as evidence from the stress-strain behaviour of confined concrete [7].…”

Axial Capacity Enhancement of CFRP Confined Columns Made of Steel Fiber Reinforced Concrete

“…Axially loaded concrete columns demonstrate enhanced strength and ductility when confined with fiber reinforced polymer (FRP) wrap at hoop direction (FRP wrap restrains lateral dilation) [1]. Due to dilation of concrete, confinement mechanism is mobilized and the lateral confining pressure develops in FRP wraps.…”