Progressive failure analysis of cylindrical shell under hydrostatic pressure based on an extended bond-based peridynamic method

A three-dimensional extended bond-based peridynamic (BPD) model, which considers the influence of internal length effect of long-range force on calculation accuracy, is proposed for progressive failure analysis of cylindrical shell subjected to hydrostatic pressure. The maximum strain criterion is introduced into the model to be a benchmark to judge whether bond breakage occurs as the hydrostatic pressure increase. Numerical results reveal that the initiation strength failure zones originated from the inner wall of the middle part of the cylinder, and are uniformly distributed at 90° in the circumferential direction. As the damage evolution continue, two new failure zones occur in the outer wall of the cylinder. Furthermore, the failure zones initiation in the inner and outer walls propagates toward to the middle surface of the cylindrical shell, and eventually they connect together. Throughout the failure evolution history, the failure degree of cylindrical shell behaves exponential growth with the loading linear increase. Once strength failure occurs, a small pressure increment would prompt the structure failure rapidly.