Research On The Similarity Of The Dynamic Response Of The Elasto-plastic Structures Subjected To Transient Loads

In this paper, based on the similarity theory, the similarity of the dynamic response of the elastic-plastic structures subjected to underwater explosion loads are discussed by numerical simulation. The major contents are listed as follows:Firstly, the similarity law of underwater explosion load is presented. The similarity criterion proposed in this paper can guarantee the similarity of underwater explosion incident waves. The pressure amplitudes and the load applying are similar, while the pulse duration shortens in geometric similarity constant.Secondly, the complete geometric similarity law of elastic-plastic structural dynamic response subjected to underwater explosion loading are proposed, and verified by numerical simulation test. After the data treatment of prototype by similarity law in this paper, the displacement, velocity, acceleration, strain and stress curves of the prototype basically coincide with those of the model.Thirdly, the dimensional analysis is sued to derive the independent Pi, dependent Pi and their similar criterion. On the basis of the actual needs, change the thickness and sectional material the independent Pi and dependent Pi, complete with geometric similarities criterions for the realization of distortional model prediction with the dynamic response of the prototype.Finally, the completely geometric similarity and distortional similarity are introduced into the development work of ship. Use the similar model as a basis to the standard form, make a certain degree of variability to shell thickness and profile size according to actual needs of the project. through the FEM predictive coefficient method, a series of distortional dynamic response of model prediction curves and equations can be got. Eventually implement the prediction of prototype's dynamic response to the distortional model. This paper aims to provide reference for the model test of warships.