For static analysis, the input file works and gives the correct result with the MPC in place.
Buckling analysis works with the MPC removed. However with the MPC in place, buckling analysis does not solve and I get an error “matrix found to be singular” in spooles.out.
I don’t think it’s stated directly in the documentation but MPCs are usually nonlinear while the *BUCKLE step is a linear perturbation procedure so I wouldn’t expect them to work together.
in case of large deformation, required to induced some imperfection (small eccentricity in loads or bowing of a members). strictly to elastic material, it can be comparable to eigenbuckling analysis.