Title: Compressive Behavior of Reinforced Concrete-Filled FRP Tubes

Author(s): H. Mohamed and R. Masmoudi

Publication: Symposium Paper

Volume: 257

Issue:

Appears on pages(s): 91-108

Keywords: column; confi nement, fi ber-reinforced polymer tube

DOI: 10.14359/20242

Date: 10/1/2008

Abstract:
In recent years, the application of concrete-fi lled fi ber-reinforced polymer (FRP) composites tubes (CFFT) for different structural applications (piles, column, girder, bridge piers) has begun. The FRP tubes benefi ts are in confi nement, protective jackets, providing shear and/or flexural reinforcement and permanent formwork. Most of the experimental investigations conducted to study the behavior of the CFFT columns under compression load were without internal longitudinal reinforcement. This paper presents the experimental results of small- and medium-height CFFT columns with internal steel bars. The parameters used in this investigation include the effect of laminate thickness of FRP tubes, concrete strength, slenderness ratio (height-to-diameter ratio) and presence of longitudinal steel bars. Sixteen CFFT specimens and one steel spiral reinforced concrete column were tested under axial compression load. The diameter of the tubes used was 152 mm (6 in.), and the fi ber orientations were mainly in the hoop direction. The results indicate signifi cant decrease of the ultimate load capacity by increasing the slenderness ratio, which also yields to different failure modes. The internal longitudinal reinforcements improve the ductility of the CFFT columns, as well as the load-carrying capacity. The ultimate strength of the reinforced CFFT columns is mainly dependent on the stiffness of the GFRP tubes. The benefi t of CFFT technique is more effective for normal-than that medium-strength concrete.