SIFCON strengthening of concrete cylinders in comparison with conventional GFRP confinement method

This paper presents SIFCON strengthening as a new method of confinement in comparison with GFRP confinement. The experimental part of the work is focused on the investigation of confinement in concrete specimens with unconfined strength ranging from 15 to 40 MPa, enclosed with GFRP sheets or SIFCON jacket. Several parameters such as number of layers and ply configuration for GFRP method and jacket strength, fiber length and jacket thickness for SIFCON method have been investigated. Furthermore, the ultimate strength models of FRP-confined concrete have been classified and evaluated with test results and the first step in modeling the ultimate strength of SIFCON-confined concrete has been taken. The results show that SIFCON confinement method can be regarded as a competitive method with respect to the well-known FRP confinement method and some of the available models of FRP confinement can also give good estimation of the ultimate strength of concrete confined by SIFCON method.

► Performance of SIFCON jackets as a new confinement method was studied.
► SIFCON jackets were compared experimentally with FRP wraps as retrofit materials.
► Behavior models of GFRP-confined concrete were verified with experimental results.
► A constant passive type confinement behavior model for SIFCON jacket is proposed.