Bending Failure Behavior of Thin-walled Composite Tube Structures

Abstract The bending failure, failure load and failure mode of thin-walled circular tubes made of carbon fiber reinforced resin matrix composites were investigated by experiments and numerical simulation. Three typical failure modes of circular tubes under bending load were observed in experiments, and the characteristics and mechanisms of different failure modes were analyzed. The results show that interlaminar shear induces the generation and propagation of microcracks at the interface of circular tubes, which accelerates the failure of circular tubes. In the bending failure process, because the interlayer performance of the round pipe is relatively low, it is the weak link of the structure, and the pipe wall is the first to produce interlayer delamination and splitting failure under the action of shear stress, resulting in structural instability and premature fracture failure. The lay-up and initial defects of thin-walled round pipe have great influence on the bending failure mode and failure load.