Abstract
In 2 dimensional problems, the utility of the vertex rotations on membrance element has been discussed and proved by a lot of researchers. However, up to now, the study of the solid element which has the vertex rotations has not been performed. Therefore, in this work, we propose the tetrahedral element including the vertex rotations based on Cook's assumption and Sekiguchi's, and these elements are applied to the free mesh method which is a kind of mesh-free method. As the result of numerical analysises made in this study, it was found that the accuracy problem of the free mesh method is eliminated by using these elements.
