Quasi-static mechanical behavior of filament wound composite thin-walled tubes: Tension, torsion, and multi-axial loading

In recent years, with the application of filament wound composite (FWC) materials in shaft structures, the mechanical behavior study of this material under related loads is urgently needed. This paper presented the experimental study on the mechanical behavior of filament wound carbon fiber reinforced polymer under uniaxial tensile loading, torsional loading, and multi-axial loading. To alleviate the stress concentration effect caused by clamping, an improved filament wound specimen was designed and produced by reinforcing each end. A new method of analysis from the inside of a winding pattern was used to investigate failure modes and behavior under different loading conditions. To further describe the mechanical behavior, the strength, stiffness, and failure mechanisms were evaluated by the stress analysis and the measurement techniques, such as the extensometer, the strain gauge, and the scanning electron microscope (SEM). The results show that the pipe is nonlinearly progressively damaged until final failure under tensile load. Brittle failure is dominant under pure torsional load. Under tension-torsional load, the pipe is progressively damaged with slight nonlinearity and the final failure strength is much lower than the pure tension or torsion load condition.