【作者】 周凡；

【导师】 吴卫国；

【作者基本信息】 武汉理工大学 ， 船舶与海洋结构物设计制造， 2014， 硕士

【摘要】 船体极限强度试验是在计算方法不成熟的背景下预报船体极限承载能力的一种有效方法，同时也可以作为一种验证计算方法精确性的手段。从极限强度概念的提出开始，极限强度试验方法就在这个领域扮演着至关重要的角色。对极限强度试验而言，设计出与原型现象相似的模型是试验成功与否的关键。但就极限强度本身，其几何非线性，材料非线性等因素耦合的强非线性不仅是计算方法的困难所在，也是试验模型相似准则导出的困难所在。传统的量纲分析方法运用到极限强度领域，因其非线性因素的干扰而产生相似程度的降低，所以为了弥补这一缺陷，本文提出了基于稳定性破坏起始量和终止量的稳定性相似模型补偿，并运用不同缩尺比模型的设计和计算验证了这一方法的可行性，并对该方法需要完善的不足之处提出了展望。本文具体工作如下：（1）运用方向性量纲矩阵推导了船舶极限强度的相似准则，以该准则为条件设计了多个缩尺比模型，对缩尺比模型的计算结果统计归纳，查找规律，发现了极限强度内在破坏机理在数据上的体现，确定了稳定性关键物理量是导致量纲分析法设计的模型产生相似程度差异的主要原因。（2）以结构极限强度破坏的原因为理论依据，在量纲分析法导出的相似准则为前提的基础上，确定了稳定性关键点（起始量和终止量）在相似关系中起到的重要作用。推导出模型非线性起始量为板格的临界应力，终止量为加筋板极限应力，在此基础上，运用方程分析法导出了模型稳定性相似准则，并运用缩尺比模型的数据说明了这一准则的适用性和正确性。同时，根据该准则对强度相似准则的补偿，设计了新缩尺比模型的结构，使之同时满足两者的要求，在这个过程中详细阐述了运用这一理论进行相似模型设计的流程步骤和注意事项，并把模型计算结果和传统设计方法设计的模型结果比较，进一步论证该方法可以提高模型的相似程度。更多还原

【Abstract】 Hull ultimate strength test is not only a effective method to predict the ultimatebearing capacity of ship but also a useful measure to verify the accuracy ofcomputing method. It plays a very important role in this field since the scientists putforward this concept.。For the ultimate strength test, the key to the success is todesign a similar model of the prototype, however the strong nonlinear factorscomposed by geometric nonlinearity and material nonlinearity are also the difficultyfor both strength computing and similarity criterion deducing.When using thedeimensional analysis method to solve ultimate strength problem, the strongnonlinear factors will reduce the similarity degree of phenomenon. In order toremedy the defect, stability compensation composed by starting point and endingpoint is put forward in this paper and is used to design different scale ratio models.The paper proves the method to be correct and propose research prospects for theshortcomings.In this paper, specific work is as follows:（1）Using the directional dimensional matrix to deduce the similarity criterionof hull ultimate strength and designing multiple different scale ratio models based onthis criterion. Computing the ultimate strength of the certain models andsummarizing the computed results to find out failure mechanism of structures. Andconfirming that the key stability physical quantities are the main reason to leaddifferent similarity level（2）Based on the theory of structural failure and similarity criterion fromdimensional method, this paper confirms that the stability starting point is criticalstress of plate and the ending point is ultimate stress of the stiffened plate. So thispaper derives the stable similarity criterion and proves the accuracy and applicability.At the same time, new scale ratio models are designed to illustrate the process andsome precautions for operation. By comparing the results of traditional designmethod and this new method, the paper demonstrates the method can improve thesimilarity degree of the models.更多还原