This BC defines boundary conditions that are constant with respect to space.
However they may change in time using the :ref:`Numeric::Interpolator::Linear` method.
In 2D, BCs are prescribed for each edge (4) and corner (4) on the boundary, for a total of 8 possible regions.
In 3D, BCs are prescribed for each face (6), each edge (12), and each corner (8), for a total of 26 possible regions.
Care must be taken to define BCs for edges/corners consistently with the faces/edges, or you will get poor
convergence and inaccurate behavior.
(See :ref:`BC::Operator::Elastic::TensionTest` for a reduced BC with streamlined load options.)
To define a boundary condition, you must define both a "type" and a "value" in each direction.
The type can be "displacement", "disp", "neumann", "traction", "trac".
The value is the corresponding value.
All BCs are, by default, dirichlet (displacement) with a value of zero.
A boundary condition for mechanics operators that simplifies frequently-used
conditions for uniaxial loading.
Types include:
- :code:`uniaxial_stress_clamp`: fixes both ends and allows for stress
concentrations at the corners.
- :code:`uniaxial_kolsky`
- :code:`uniaxial_stress`: 1D stress problem
- :code:`uniaxial_strain`: 1D strain problem
Use expressions to define space and time varying boundary conditions
for elastic problems.