Tests for Quad9 element

[SerafeimBakalakos]

Does anyone have tests for Quad9 elements regarding the stiffness matrix, (consistent) mass matrix, equivalent forces, etc? I cannot seem to find any tests in my books and Abaqus doesn't even support Quad9, so I cannot test against it.

[dimtsap]

@SerafeimBakalakos We can check together Code Aster. It supports all of our 2D and 3D (apart from Pyra14 I think). Thus, if it has a matrix extraction procedure like Abaqus we could cross-ckeck them all.