An elastic link element connects two nodes to act as an element, and the user defines its stiffness. Truss or beam elements may represent elastic links.
However, they are not suitable for providing the required stiffness with the magnitudes and directions that the user desires. An elastic link element is composed of three translational and three rotational stiffnesses expressed in the ECS.
The translational and rotational stiffnesses of an elastic link element are expressed in terms of unit force per unit length and unit moment per unit radian respectively. Figure 1.62 presents the directions of the ECS axes. An elastic link element may become a tension-only or compression-only element, in which case the only directional stiffness can be specified is in the ECS x-axis.
Examples for elastic link elements include elastic bearings of a bridge structure, which separate the bridge deck from the piers. Compression-only elastic link elements can be used to model the soil boundary conditions. The rigid link option connects two nodes with an “infinite” stiffness.