Concentrated stiffness
This element defines a stiffness for a given degree of freedom.
It can be used for instance for a foundation for which the stiffness originates only from a solid-solid contact element. It can also be used as a linear spring between the initial position and the actual position of the node.
This element can only be used with law LSTIFF
Type: 17
Implemented by: AM Habraken, 1992
Prepro: STIFFA.F
Lagamine: STIFFB.F
| Line 1 (A5) | |
|---|---|
| TITLE | “STIFF” in the first five columns |
| Line 2 (I5) | |
| NELEM | Number of elements |
| Definition of the elements (2I5/5I5) repeated NELEM times | |
| LMATE | Material law |
| LSPRING | = 1 if use as a spring; an associated force is calculated (stiffness of law LSTIFF multiplied by the node displacement along the relevant DoF between the initial and actualized position) = 0 if use as stiffness only (no associated force) |
| NODES | Node number |
| IDDL | Number of the degree of freedom |
Sigma: Effort in the spring if LSPRING = 1 ; else nothing