1. Discretization

1.1. Degrees of freedom

For the two three-dimensional models, the degrees of discretization freedom are, at each node of the support mesh, the three translational displacement components or the six components (three translations and three rotations).

Finished element	Degrees of freedom (at vertex nodes)
DIS_T	DX	DY	DZ
DIS_TR	DX	DY	DZ	DRX	DRY	DRZ

1.2. Support mesh for stiffness matrices

The support cells for discrete elements, in displacement formulation, are segments with two nodes SEG2 or point cells POI1 combined with one node:

For « POI1 » meshes, the efforts are calculated from the differences in the degrees of freedom of the mesh node with the fixed coordinate system, while for « SEG2 » meshes, they are calculated from the differences in the degree of freedom between the two nodes.