Englesun,
It seems this problem may be solved using a Dyna3D approach (explict FE formulations) and nonlinear contact. When the strut breaks (loses contact) the program may still continue depending on certain rigid body factors that might be controlled through contact modeling.
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Donnis,
You can get some limited DOF software FEA tools from Cranes Software who now markets the NISA suite of tools for the price you are looking to spend. My understanding is that these are fully capable in funtions and element types, but limited in problem size (degrees of freedom)...
