Abstract Ship structures may be subjected to repeated random patch loads at different locations. Under these circumstances, ship plates will have large accumulated permanent deformations, which will result in some serious negative effects on their work and safety performance. Therefore, the elasto-plastic response of ship structure under repeated patch loads at different locations are studied by using finite element method. The permanent deformations of plate in the whole loading and unloading process are investigated. In addition, the residual stress and plastic strain states of the panel and stiffeners are studied based on a typical wheel-on-deck interaction scenario. Moreover, according to Hughes's hypothesis, the equivalent method between repeated patch loads at different locations and full uniform pressure load is studied. Considered the influence of plate slenderness, the improved formula for equivalent load coefficient is proposed, showing a good correlation with experimental data and numerical results. The proposed equivalent method can be used for estimating the permanent deformations of ship structures under repeated patch loads at different locations in ship life.

中文翻译：

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不同位置重复贴片载荷作用下船板塑性变形-弹塑性数值分析与设计方程

摘要 船舶结构可能会在不同位置承受重复的随机补丁载荷。在这种情况下，船板会产生较大的累积永久变形，从而对其工作和安全性能造成严重的负面影响。因此，采用有限元方法研究了船舶结构在不同位置重复贴片载荷作用下的弹塑性响应。研究了整个装卸过程中板材的永久变形。此外，基于典型的轮对甲板相互作用场景研究了面板和加强筋的残余应力和塑性应变状态。此外，根据休斯的​​假设，研究了不同位置的重复贴片载荷与完全均匀压力载荷之间的等效方法。考虑板细长的影响，提出了等效载荷系数的改进公式，与实验数据和数值结果具有良好的相关性。所提出的等效方法可用于估计船舶结构在船舶寿命中不同位置重复贴片载荷下的永久变形。