ospgrid.grid.Member#

class Member(idx, node_i, node_j, EI, GJ)[source]#

Bases: object

Object encapsulating the properties for a grid member

Initialize the member object

Parameters:

  • idx (int) – The member index in the grid.

  • node_i (Node) – The start node of the member.

  • node_j (Node) – The end node of the member.

  • EI (float) – The flexural rigidity.

  • GJ (float) – The torsional rigidity.

Return type:

None.

Methods

get_global_stiffness

Returns the member stiffness matrix in global coordinates with nodal DOFs in the order DZ ('vertical' force), RX (torsion), RZ (bending moment).

get_local_stiffness

Returns the member stiffness matrix in local coordinates with nodal DOFs in the order DZ ('vertical' force), RX (torsion), RZ (bending moment).

get_transformation_matrix

Gives the transformation matrix relating the member degrees of freedom from local to global coordinate system.
get_local_stiffness()[source]#

Returns the member stiffness matrix in local coordinates with nodal DOFs in the order DZ (‘vertical’ force), RX (torsion), RZ (bending moment).

Returns:

K – Member stiffness matrix in local coordinates.

Return type:

np.ndarray

get_transformation_matrix()[source]#

Gives the transformation matrix relating the member degrees of freedom from local to global coordinate system.

It considers only the grid member DOFs, per get_local_stiffness()

Returns:

T – Transformation matrix

Return type:

np.ndarray

get_global_stiffness()[source]#

Returns the member stiffness matrix in global coordinates with nodal DOFs in the order DZ (‘vertical’ force), RX (torsion), RZ (bending moment). This shows the stiffness contributions of the member to the global DOFs.

Returns:

Kg – Member stiffness matrix in global coordinates.

Return type:

np.ndarray