Response Analysis For Sandwich Structure

With the widely use of new material and technique in shipbuilding, sandwich plate structure had been widely accepted because of her excellent characteristic. Sandwich plate is a modern structure, which has been developed in recent years, and it has her specific characteristic, which was high stiffness, light, easily to design and quickly molded in contrast with isotropic material. On the other hand, it has it's own disadvantage, such as anisotropy, hard to extend and complicated, which lead the mechanics to an intricate extend. As a result the study of sandwich plate plays an important role in its research and application. So it's necessary for us to study it.On the basis of finite element method, damping and calculation of added mass, we make a study of dynamic and response analysis in frequency domain on the sandwich structure with respect to the development of sandwich structure. Then we make a further study of damaged sandwich structure. The following is presented in the article:In the first chapter, we point out the reason and possibility to select this topic and summarize the history and actuality of the sandwich structure, and then we introduce the way and method of the article in the second chapter. Then in Chapter 2, the 4-node quadrilateral shell element is deduced according to the Reissner assumption, then take a example of four-side rigid plate to validate the theory and programmer. In Chapter 3,we devoted to study of dynamic problem in the vibration system, during the course; we introduce the common model of damping, including the linear damping, the nonlinear damping and mode damping. At last, we make a dynamic and response analysis in frequency domain of a cantilever. In chapter 4, the methods to calculate the added mass, including the Morison formula, numerical and experience formula is covered in this chapter. Then point out how to calculate added mass in ship domain. In chapter 5, The influences of damage parameters such as damage position, damage size, damage extension have been discussed to study their influence to structural static and dynamic characteristics. A numerical panel model has been designed and analyzed.