Multiple surface crack interaction of non-coplanar cracks

Hollow cylinders represent one of the important elements in the industry. It is widely recognized that fracture characterizes the predominant mode of failure in cylindrical structures, which is precipitated by inherent imperfections or flaws. Over a period, these imperfections (cracks) may propagate and culminate in catastrophic failure, thereby presenting considerable hazards to both the surrounding ecosystem and human safety. Cracks can be single or multiple, and when they are in the multiple form, they can interact to increase pressures that are higher than what the material can withstand. Thus, this paper examines the influence of the interaction between double parallel non-coplanar cracks located on the external surface of a thick hollow cylinder subjected to remote tension and bending loading. Two sorts of separation distances were examined in this study, horizontal (s) and angular (α). The obtained stress intensity factor via finite element analysis was used to quantify the interaction factor along the crack front. The obtained results exhibited that both amplification and shielding interaction impacts could be observed along the crack front for a non-coplanar crack configuration. Additionally, both cracks exhibited the same interaction influence, but in opposite directions. The angular separation distance exhibited a significant influence on the interaction factor, this impact was strongly affected by the shape of the crack.