elastic_isotropic

Isotropic linear elastic continuum material for OpenSees nD elements.

Attributes

all `module-attribute`

__all__ = ['ElasticIsotropicMaterial']

Classes

Material

Material(material_type: str, material_name: str, user_name: str)

Bases: ABC

Abstract base class for manager-owned OpenSees material objects.

Material instances do not self-register and do not assign their own tags. A :class:~femora.core.material_manager.MaterialManager owns lifecycle operations, tag assignment, removal, and retagging for a local model context.

Parameters:

Name	Type	Description	Default
`material_type`	`str`	OpenSees material category (e.g. `'nDMaterial'`).	required
`material_name`	`str`	Concrete OpenSees material name (e.g. `'ElasticIsotropic'`).	required
`user_name`	`str`	User-specified label for this material instance.	required

Attributes:

Name	Type	Description
`tag`	`Optional[int]`	Manager-assigned OpenSees material tag. Remains `None` until this object is added to a :class:`~femora.core.material_manager.MaterialManager`.
`_owner`	`object \| None`	Reference to the owning manager, or `None` when unmanaged.

Methods:

to_tcl `abstractmethod`

to_tcl() -> str

Render the OpenSees material definition command as a Tcl string.

updateMaterialStage

updateMaterialStage(state: str) -> str

Return an updateMaterialStage Tcl command, or empty string.

set_parameter

set_parameter(parameter_name: str, new_value: Union[float, int, str, None] = None, element_tags: Optional[List[int]] = None) -> str

Return a setParameter Tcl command, or empty string.

get_param

get_param(key: str) -> Any

Return the value of a stored parameter by key.

ElasticIsotropicMaterial

ElasticIsotropicMaterial(user_name: str = 'Unnamed', *, E: float | None = None, nu: float | None = None, rho: float = 0.0, **_: Any)

Bases: Material

Homogeneous isotropic elastic material for continuum nD analysis.

This class represents the OpenSees ElasticIsotropic nD material model. The constitutive response is defined by Young's modulus and Poisson's ratio, with optional density for analyses that require material mass.

Tcl form

nDMaterial ElasticIsotropic <tag> <E> <nu> <rho>; # user_name

Note

Coordinate E, nu, and rho with the unit system used by the mesh and exported Tcl model.
rho defaults to 0.0 for stiffness-only definitions.

Attributes:

Name	Type	Description
`tag`	`Optional[int]`	Manager-assigned identifier after registration with the owning material manager.
`params`	`Dict[str, float]`	Validated parameter values keyed by `E`, `nu`, and `rho`.

Example

from femora.core.model import Model

model = Model()
mat = model.material.nd.elastic_isotropic(
    user_name="sand",
    E=3.0e7,
    nu=0.3,
    rho=2000.0,
)
print(mat.tag)

Create an elastic isotropic material with validated parameters.

Parameters:

Name	Type	Description	Default
`user_name`	`str`	Label included in the emitted Tcl comment and stored by the owning material manager.	`'Unnamed'`
`E`	`float \| None`	Young's modulus. Must be a positive numeric value.	`None`
`nu`	`float \| None`	Poisson's ratio. Must be numeric and in the range `[0, 0.5)`.	`None`
`rho`	`float`	Mass density. Must be a non-negative numeric value.	`0.0`
`**_`	`Any`	Additional keyword arguments accepted and ignored for forward-compatible factory calls.	`{}`

Raises:

Type	Description
`ValueError`	If `E` or `nu` is missing, if any numeric parameter cannot be converted to `float`, if `E` is not positive, if `nu` is outside `[0, 0.5)`, or if `rho` is negative.

Methods:

to_tcl

to_tcl() -> str

Render the OpenSees nDMaterial ElasticIsotropic command.

Returns:

Name	Type	Description
`str`	`str`	Tcl command defining this material with its assigned tag and validated parameters, ending with `; # user_name`.

Raises:

Type	Description
`ValueError`	If this instance has no manager-assigned tag yet.

elastic_isotropic