Does anyone know which MSC NASTRAN card outputs the element local stiffness matrix for a single CBAR (12-dof) beam element? I have a 12-dof beam with some pin (dof) releases and need to run a simple test problem to check the element local stiffness matrix, to compare to some calculations in another analysis.
In case the above won't work, here's the first test problem, in case anyone could cut and paste the 12 x 12 standard stiffness matrix (neglecting transverse shear distortion effects). Node 1 at (0,0,0). Node 2 at (-0.7071068,0,-0.7071068). Element local z' axis lies in global xz plane and points somewhat toward positive z direction. E = A = L = Iy' = Iz' = J = 1. Iy'z' = 0. G = 0.400. Element end 1 dof 5 (rotation about local y' axis) is released (freed to rotate).
Here's the second test problem. Same as above except element end 1 dofs 4 and 5 are released (freed), and element end 2 dofs 5 and 6 are released.
If the above won't work (as might be the case in certain programs), then I can change the problem to Iy' = Iz' = 0.08333333. J = 0.1666667. (By the way, Poisson's ratio is 0.25.). Any help is appreciated.
In case the above won't work, here's the first test problem, in case anyone could cut and paste the 12 x 12 standard stiffness matrix (neglecting transverse shear distortion effects). Node 1 at (0,0,0). Node 2 at (-0.7071068,0,-0.7071068). Element local z' axis lies in global xz plane and points somewhat toward positive z direction. E = A = L = Iy' = Iz' = J = 1. Iy'z' = 0. G = 0.400. Element end 1 dof 5 (rotation about local y' axis) is released (freed to rotate).
Here's the second test problem. Same as above except element end 1 dofs 4 and 5 are released (freed), and element end 2 dofs 5 and 6 are released.
If the above won't work (as might be the case in certain programs), then I can change the problem to Iy' = Iz' = 0.08333333. J = 0.1666667. (By the way, Poisson's ratio is 0.25.). Any help is appreciated.