One-dimensional linear elasticity

[ahenkes1]

Modulus Pull Request

Corresponds to issue #150

Description

This Pull Request enables the usage of one-dimensional linear elasticity in Modulus-Sym. Previously, linear elasticity was only supported for the two- and three-dimensional case.

In the code base, the 1D case was separated from the 2D and 3D case, as it relies only on Young's modulus "E" instead of Lame's constants. The code for 2D and 3D use Lame's constants extensively.

Care was taken, that also inhomogenous distributions of E are allowed, i.e., E(x).

Checklist

• [x] I am familiar with the Contributing Guidelines.
• [x] New or existing tests cover these changes.
• [x] The documentation is up to date with these changes.
• [x] The CHANGELOG.md is up to date with these changes.
• [x] An issue is linked to this pull request.

Dependencies

None