Abstract Crack damage is commonly found in aged hull structure severely affecting the ultimate compressive strength. A numerical study is comprehensively carried out to reveal the ultimate strength reduction behaviors of steel unstiffened cracked plate. The parameters such as crack length, angle and positions as well as the plate aspect and slenderness ratios were taken into account in the FE models. The crack was assumed to be through-thickness with no faces contact and propagation. Reasonable element type and size, crack width and tip shape were adopted based on a series of sensitivity analyses. It is concluded that the real length of longitudinal crack, projected lengths of transverse and inclined cracks, their transverse positions and slenderness ratio significantly influence the plate ultimate strength, while effects of aspect ratio and longitudinal position are not crucial. Based on the numerical results, two empirical formulas as a function of the critical parameters were proposed for predicting the residual ultimate strength of ship plates with longitudinal crack, transverse or inclined cracks, respectively.

中文翻译：

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带裂纹钢无筋板残余极限强度的研究

摘要 老化船体结构中普遍存在裂纹损伤，严重影响极限抗压强度。综合数值研究揭示了钢无加强裂纹板的极限强度折减行为。有限元模型考虑了裂纹长度、角度和位置以及板纵横比和长细比等参数。裂纹被假定为贯穿厚度，没有面接触和传播。在一系列敏感性分析的基础上，采用了合理的单元类型和尺寸、裂纹宽度和尖端形状。得出的结论是，纵向裂纹的实际长度、横向和倾斜裂纹的投影长度、横向位置和长细比对板的极限强度有显着影响，而纵横比和纵向位置的影响并不重要。基于数值结果，提出了两个作为临界参数函数的经验公式，分别用于预测具有纵向裂纹、横向或倾斜裂纹的船板的残余极限强度。