毕业论文移动版

摘要船舶长期航行于海水中，易遭受腐蚀。此外，油舱、压载水舱等液体舱室也会腐 蚀舱壁及船体其它构件。腐蚀使板厚减小，构件更容易屈曲，势必会降低船体的结构 强度，使船舶更易失稳。尤其是老龄船舶，往往其腐蚀损伤严重，船体结构强度下降 更大，因此，需准确估算考虑腐蚀后的剩余极限强度，来保证老龄船舶航行时的安全 性。对板材均匀腐蚀的研究已经较多，但点腐蚀的研究仍较少。现在船舶多采用高强 度钢，不易发生均匀腐蚀，腐蚀的主要形式为点腐蚀。需要对点蚀进行更多的研究。77829

船舶由板材及纵横交错的骨材组成，其受力由加筋板传递，要计算船体结构的极 限强度，首先要算出加筋板的极限强度。

本文研究考虑点腐蚀后加筋板的极限强度，主要研究内容如下：

（1）掌握非线性有限元的基本方法及结构极限强度的相关理论，学习有限元软件ANSYS，并掌握建模方法； 

（2）对含点腐蚀损伤的加筋板进行轴向压缩试验，分析试验结果； 

（3）用 ANSYS 软件建立无初始变形含点腐蚀损伤的加筋板模型，计算其极限强度， 并分析点蚀位置、深度和直径对加筋板极限强度的影响。 

毕业论文关键词：腐蚀损伤；极限强度；加筋板模型；

Abstract Ships sails in the sea for a long time, they are easy to suffer from corrosion。 In addition, the bulkhead and other parts of the oil tank, ballast water tank and other liquid compartments will also be corroded。 The thickness of the plate will be decreased by corrosion, the component is more easy to buckling, it is bound to reduce the structural strength of the hull, so that the ship is more likely to lose stability。 In particular, the aging ship, the corrosion damage is often serious, the strength of the hull structure is even greater, therefore, it is necessary to accurately estimate the residual ultimate strength  after corrosion, in order to ensure the safety of the aging ship。 There was a lot of research on the uniform corrosion of the plate, but the research on the point corrosion is still less。 Now more ships use high strength steel。 The main form of corrosion becomes pitting corrosion instead of uniform corrosion。 As a result, more research on pitting corrosion are needed。

The ship are composed by the plates and intricate frames, the force are transmissed by stiffened plates。 To calculate the ultimate strength of the hull structure, the  ultimate strength of stiffened plates must be calculated in advance。

In this paper, we discuss the ultimate strength of stiffened plate with pitting corrosion。

The main research contents are as follows:

（1）to master the basic method of nonlinear finite element and the related theory of the ultimate strength of the structure, study the finite element software ANSYS, and master the modeling method;

（2）axial compression tests were carried out on the stiffened plate with pitting corrosion 。

The experimental results are analyzed。

（3）the ANSYS software is used to establish the model of the reinforced plate without initial deformation, the ultimate strength of the model was calculated, and the influence of the location, depth and diameter on the ultimate strength of the stiffened plate was analyzed;

Keywords: corrosion damage; ultimate strength; stiffened plate model;

目 录

第一章  绪论 1

1。1 本文研究的目的和意义 1

1。2 研究的背景 1

1。2。1 船体结构 1

1。2。2 海水腐蚀的影响 (责任编辑：qin)