Concrete-filled FRP tubes: New forms for improved confinement effectiveness

Abstract

This paper reports on the development and testing of a new concrete-filled fiber reinforced polymer (FRP) tube (CFFT) system. The CFFT system was designed to enhance the effectiveness of rectangular FRP tubes in confining concrete. The technique used in the development of the CFFT system involved the incorporation of an internal FRP panel as an integral part of the CFFT. The performance of the system was investigated experimentally through axial compression tests of six unique CFFTs. The results of the experimental study indicate that the new CFFT system presented in this paper offer significantly improved performance over conventional CFFTs with similar material and geometric properties. Examination of the test results have led to a number of significant conclusions in regards to confinement effectiveness of each new CFFT system. These results are presented and a discussion is provided on the parameters that influenced the compressive behavior of the new CFFT system.