散货船隔舱重载下极限强度简易计算方法研究

散货船在装载矿石等重货时，通常只装载在奇数货舱内，这就是所谓的隔舱重载工况。在这种工况下，中间舱的双层底结构除受到总纵弯曲作用外，还会受到邻舱重货引起的局部弯曲作用，而且该局部弯曲的作用会降低中拱状态下船体梁的极限强度。文章提出了一种简易计算方法，顶边舱结构和底边舱结构可以看作两根梁，双层底结构可视作正交异性板，运用双梁理论和正交异性板理论可推导出局部弯曲的影响。然后，考虑该局部弯曲的作用，用Smith法计算船体梁的极限强度。最后，将文中方法计算的结果与FEM结果进行比较，并对结果进行了分析。

Simple method to evaluate ultimate hull girder strength of bulk carrier in alternate heavy loading condition

When heavy cargos such as ore are loaded on bulk carrier, they are usually loaded only in cargo holds of an odd number, which is called alternate heavy loading condition. Under such situation, double bottom structure is subjected to local bending, and this reduces the ultimate hull girder strength in hogging. In this paper, a simple method is proposed which can account for the influence of local bending of double bot-tom on the ultimate hull girder strength in the framework of Smith’s method. Two-beam theory is applied and local bending of double bottom as a plate is also considered. The calculated results are compared with the FEM results, and the proposed method is assessed.