ElasticBeamColumnElement

ElasticBeamColumnElement(ndof: int, section: Union[Section, int, str], transformation: Union[GeometricTransformation, int, str], massDens: float = 0.0, cMass: bool = False, **kwargs)

Bases: Element

Linear elastic beam-column element for frame models.

This two-node element uses aggregate section stiffness and a geometric transformation to represent linear elastic frame response. It supports 2D models with 3 DOFs per node and 3D models with 6 DOFs per node.

Tcl form

element elasticBeamColumn <tag> <iNode> <jNode> <secTag> <transfTag> <-mass massDens> <-cMass>

Note

Requires a managed Section and GeometricTransformation with assigned tags before Tcl export.
Stiffness comes from the section definition, not a direct material assignment on the element.

Attributes:

Name	Type	Description
`massDens`		Mass density per unit length used for optional lumped or consistent mass matrix formation.
`cMass`		When `True`, request a consistent mass matrix instead of the default lumped formulation.

Example

from femora.core.model import Model
import femora.components.section.beam  # noqa: F401

model = Model()
sec = model.section.beam.elastic(
    user_name="Column",
    E=29000.0,
    A=20.0,
    Iz=500.0,
    Iy=500.0,
    G=11200.0,
    J=10.0,
)
transf = model.transformation.transformation3d(
    transf_type="Linear",
    vecxz_x=0.0,
    vecxz_y=0.0,
    vecxz_z=1.0,
)
ele = model.element.beam.elastic(
    ndof=6,
    section=sec,
    transformation=transf,
)
print(ele.tag)

Create an ElasticBeamColumnElement with validated dependencies.

Parameters:

Name	Type	Description	Default
`ndof`	`int`	Number of DOFs per node. Must be 3 for 2D or 6 for 3D.	required
`section`	`Union[Section, int, str]`	Managed section object defining axial and bending stiffness.	required
`transformation`	`Union[GeometricTransformation, int, str]`	Managed geometric transformation defining the local element axis.	required
`massDens`	`float`	Optional mass per unit length for dynamic analyses.	`0.0`
`cMass`	`bool`	When `True`, use a consistent mass matrix.	`False`
`**kwargs`		Additional element parameters stored on the base element.	`{}`

Raises:

Type	Description
`ValueError`	If `ndof` is unsupported, if the section or transformation is missing, if mass density is negative, or if dependencies cannot be resolved.

Methods:

get_mass_per_length

get_mass_per_length() -> float

Return the mass density per unit length.

Returns:

Type	Description
`float`	Mass per unit length assigned to this element.