To make sure that it’s not a modeling error, I submitted the same input file in Abaqus and got correct results. Am I missing some special characteristic of truss elements in ccx ?
I’have observed weird results on that beam under compression.
It is the same file posted but once refined.
When using ccx_dynamic.exe for windows both pardiso and Pastix gives weird results.
¿May i have some missing dll. Does it happen to someone else?
above example are for truss element, so it does not required mesh to be refined. only use one element mesh betwen each joint of connected members. spliting and refining mesh may cause stability problem and spurious movement since each element end nodes become hinged.
Again, it seems to be handled differently by various solvers. In Abaqus there’s no such spurious deformation in this example when multiple truss elements are used.
Changing the force direction also fails.
I have build and refine a truss with a mass at the end expecting it to behave as a pendulumm (chain) but it fails so it should not be exactly a hinged connection.
you could try changie and use the element to B31R rather than T3D2 to avoid any unexpected behaviour due to unstable structure problems. even it’s a beam element the bending effect did not take into account, these beam are expanded to C3D8R element with only one integration point.
Apparently, Abaqus handles those redundant boundary conditions differently.