Stiffness Elements > Stiffness Parameters

Definition of a user-defined stiffness matrix. The stiffness matrix is related to the local coordinate system of the element. Any required direction or eccentricity transformation is performed by the program in accordance with the defined angle and eccentricity parameters.

Setting	Description
From/To/Step	Element series, for which the section properties are input/modified.
Element type	Type of the element(s) (see Structure > Elements > Info )
Aero class / EccType	Irrelevant in this context
Stiffness Matrix	Input window for entering the components of the 4 sub-matrices of the stiffness matrix K11: The Matrix K11 describes the interaction between the (local) DOF's of the start node. The input is omitted when the number of the start node is zero. K12: The Matrix K12 describes the interaction between the (local) DOF's of start node and those of the end node. No input is required if one of the nodes of the element is zero. K21: The Matrix K12 describes the interaction between the (local) DOF's of end node and those of the start node. No input is required if one of the nodes of the element is zero. K22: The Matrix K22 describes the interaction between the (local) DOF's of the end node. The input is omitted when the number of the end node is zero.

Note: User-defined length and force units are considered, but angle unit for rotations is always Radians!