THE EQUIVALENT SPRING ELEMENTS TO THE ANALYSIS OF TWO AND THREE DIMENSIONAL CONTINUUM

A method to derive the equivalent spring elements for the analysis of a two or a three-dimensional continuum is studied, and it is used in the static and dynamic analysis of the interaction in a vessel structure and its storages. At first, the theories of the equivalent spring elements to the two or three dimensional continuum are given, based on the principle of equval stiffness. Secondly, the two dimensional equivalent spring elements (ESE-2D) are used in the analysis of the pressure distribution in the vessel structure, and the three dimensional equivalent spring elements (ESE-3D) are used in the dynamic interaction of the vessel structure and its storages. The numerical tests show that the proposed ESE method can provide more efficient and higher precise computational models than the traditional finite element method for a continuum. Comparing with the added mass method, the ESE method can calculate not only more efficiently, but also more correctly in the analysis of the dynamic interaction in a vessel structure and its storages. The proposed equivalent-spring-elements method can be used widely to the mechanics analysis of engineering problems.