| 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. |
