Research on enhancement of low yield point steel pipes by fiber composite materials

Abstract

This paper mainly studies on enhancement of low yield point steel pipes by fiber composite materials. By conducting compression tests on five specimens of fiber-steel pipe mortar columns (FSPMCs), the failure modes and load deformation relationships of the specimens are discussed. Based on the properties of specimens, further finite element analysis is conducted. The comparison of the results shows that the finite element analysis is in good agreement with the test results. Furthermore, parameter analyses are conducted on the different layers and overlapping allowances of aramid fiber reinforced plastic (AFRP) and carbon fiber reinforced plastic (CFRP). It is found that the bearing capacity of fibers on steel pipe mortar columns increases with the increase of fiber layers, and increases with the decrease of overlapping allowances. The bearing capacity of CFRP-wrapped steel pipe mortar columns is about 1.1–1.5 times that of AFRP. When the overlap allowance is 0°, the bearing capacity of CFRP is 19.1 % higher than that of AFRP. In addition, this paper proposes a calculation method for the bearing capacity of FSPMCs. The results show that the error rates between the theoretical calculation results and the test results are within 6 %, indicating that the proposed method has sufficient accuracy and can provide valuable references for subsequent research and engineering applications.