摘 要

船舶加筋板的极限强度无论是对船舶总纵强度还是局部强度都有着重要影响，历来是船舶强度研究的热点问题。本文从结构优化设计和凹陷损伤评估两个方面出发，利用非线性有限元方法对新型的悬挂式铝合金加筋板的极限强度性能展开研究，为结构优化设计和凹陷损伤的评估提供指导。

本文的主要工作有：

（1）从结构优化设计的角度出发，计算分析了板厚、加强筋腹板高度、加筋形式对悬挂式铝合金加筋板极限强度性能的影响。计算结果显示，在板厚位于2~8mm范围内时，随着板厚的增加，加筋板的极限强度也随之增大，相较于板厚为2mm时，板厚为8mm时极限强度增大了36.1%，当板厚增大到6mm后对极限强度的影响减弱，极限强度增幅由12.4%衰减至2.2%；当加强筋腹板高度位于30~70mm范围内时，随着加强筋腹板高度的增加，极限强度随之增加，相较于腹板高度为30mm时，腹板高度为70mm时，极限强度增加了5.6%，但当加强筋腹板高度增加至50mm时，腹板高度对极限强度的影响减弱，极限强度增幅由2.7%衰减至0.5%；在截面面积相同的情况下，加强筋形式为T型的加筋板与角型的加筋板极限强度相同，与扁型加筋板极限强度相差17.4%，而T型加筋板更适用于悬挂式铝合金加筋板结构。

（2）对板的凹陷损伤影响参数，凹陷深度、造成凹陷的刚体截面面积和接触面形状展开分析计算，评估凹陷损伤对悬挂式铝合金加筋板极限强度性能的影响。计算结果显示，当凹陷深度小于6mm时对极限强度影响较小，极限强度衰减幅值仅在2.2%，6mm至38mm，极限强度迅速减弱，衰减幅值在5.4%左右，最后在凹陷深度为38mm时，相较于无凹陷情况，极限强度下降了23.0%；随着刚体截面面积由0向7921mm²增大，极限强度随之减小，相较于无凹陷情况，刚体截面积为7952mm²时，极限强度下降了9.8%；带有正方形、圆形、柱形曲面这三种接触面形状造成的凹陷的加筋板极限强度仅相差2.3%，加筋板极限强度性能的影响规律几乎一致。

关键词：极限强度；悬挂式铝合金加筋板；结构优化设计；凹陷损伤

ABSTRACT

The ultimate strength of ship stiffened panels has an important influence on both the overall longitudinal strength and the local strength of ships, and has always been a hot issue in ship strength research. Starting from two aspects of structural optimization design and dent damage, this paper studies the ultimate strength performance of a new type of stiffened aluminium panels with floating transverse frame by using nonlinear finite element method to provide guidance for structural optimization design and dent damage evaluation.

The main work of this paper is as follows:

(1) From the point of view of structural optimization design, the influences of panel thickness, web height of stiffeners and types of stiffeners on the ultimate strength performance of stiffened aluminium panels with floating transverse frames are calculated and analyzed. The results show,that when the panel thickness is in the range of 2~8mm,the ultimate strength of stiffened panels increases with the increase of panel thickness,compared with 2mm,the ultimate strength of 8mm increases 36.1%,but after 6mm,the influence of panel thickness on the ultimate strength decreases,the attenuation amplitude of ultimate strength decrease from 12.4% to 2.2%; when the web height of the stiffener in the range of 30~70mm,the ultimate strength increases with the increase of the web height of the stiffener,compared with 30mm,the ultimate strength of 70mm increases 5.6%, but, when the height increases to 50mm, the influence of web height on the ultimate strength begins to decrease,the amplification of ultimate strength decreases from 2.7% to 0.5%; Under the condition of the same cross-sectional area, the ultimate strength of T-shaped stiffened panels identical to the angle-shaped stiffened panels, which is 17.4% different from that of flat stiffened panels, but T-shaped stiffened panels are more suitable for stiffened aluminium panels with floating transverse frame structures.

(2) The influence parameters of the panel’s dent damage, dent depth, cross-sectional area of the rigid body and the shape of the contact surface that produce the dent damage are analyzed and calculated to evaluate the influence of dent damage on the ultimate strength performance of stiffened aluminium panels with floating transverse frames. The calculation results show ,that when the dent depth less than 6mm,has less influence on the ultimate strength,the attenuation amplitude of ultimate strength only is 2.2%, but 6mm~38mm, the ultimate strength decreases rapidly,the attenuation amplitude of ultimate strength is retain 5.4%,finally,when the dent depth is equal to 38mm,compared with perfect condition,the ultimate strength decreases 23.0%; as the cross-sectional area of the rigid body increases from 0 to 7921 mm², the ultimate strength

decreases,when the cross-sectional area is equal to 7921mm²,compared with perfect condition，the ultimate strength decreases 9.8%；The difference in ultimate strength of stiffened panels with dent damage caused by square, circular and cylindrical curved surfaces is only 2.3%, and the influence of ultimate strength performance of stiffened panels are almost the same.

Key words: ultimate strength; stiffened aluminium panels with floating transverse frame; structural optimization design;dent damage

目录

第一章 绪论 1

1.1研究背景 1

1.2研究现状概述 1

1.2.1经验公式法 1

1.2.2解析法 2

1.2.3试验法 4

1.2.4有限元法 5

1.3本文的主要工作 7

第二章 有限元方法设计 9

2.1边界条件 9

2.2单元类型 10

2.3非线性求解方法 11

2.4模型范围 11

2.5网格尺寸 13

2.6初始缺陷 15

2.7有限元方法验证 16

第三章 模型有限元计算结果及分析 17

3.1模型介绍 17

3.2有限元计算结果及分析 18

3.3本章小结 20

第四章 结构优化参数分析 21

4.1概述 21

4.2加筋板板厚 21

4.3加强筋腹板高度 24

4.4加强筋形式 27

4.5本章小结 30

第五章 凹陷损伤评估 31

5.1 概述 31

5.2凹陷深度 31

5.2.1计算流程 31

5.2.2计算结果及分析 31

5.3造成凹陷的刚体截面面积 34

5.3.1计算说明 34

5.3.2 计算结果与分析 35

5.4 接触面形状 38

5.4.1计算说明 38

5.4.2计算结果与分析 39

5.5 本章小结 40

第六章 总结与展望 41

参考文献 43

致谢 46

第一章 绪论

1.1研究背景

船舶结构强度问题是船舶研究的重中之重，这不仅仅是从经济性方面的考量，更是船员及乘客生命安全的必要保证。加筋板作为船体结构的重要构件，广泛存在于各船舶结构中，其强度无论是对船体局部强度而言还是总体强度而言都起着至关重要的作用。

随着船舶逐渐向轻量化、高速化发展，铝合金以其优良的比强度性能走进船舶行业中，并已在一些高速舰艇、气垫船等特殊类型船舶结构中得到应用，铝合金结构的极限强度问题也逐渐成为船舶结构强度研究的热点。然而，铝合金加筋板结构的研究还存在一些有待发展的地方：