Research on the mechanism of the impact of elastic shakedown and dent parameter coupling on the ultimate strength of hull plates under cyclic loading

Objectives To investigate the effects of dents, initial welding deformation and residual stress on the ultimate strength of hull plates under cyclic loading. Methods ABAQUS software is used to analyze the effect of different dent sizes on the ultimate strength of hull plate with initial defects under the state of elastic shakedown. The model and working conditions are constructed by considering multiple factors (weld residual stress, material properties, etc.). Results The results indicate that welding residual stress have a significant impact. An increase in dent depth after the state of elastic shakedown reduces residual stress release and intensifies the plastic deformation, leading to a decrease in ultimate strength. The aspect ratio of dents has a complex influence and is related to stress release. Conclusions This study confirms that the release of welding residual stress and dent parameters under cyclic loading have significant effects on the ultimate strength of hull plates with dents, and offers practical guidance for the design and optimization of the hull structure.