Nonlinear Buckling Analysis

A linear buckling analysis gives an approximation to the critical load of a structure. To gain more confidence in the results, a full nonlinear analysis where the load is slowly increased can be performed. Such an analysis will, in general, not give a distinct value of the buckling load. Rather, there will be an increasing level of deviation from the linear response. The allowable load is given by some criterion of allowable deformation or stress. In some cases, the nonlinear buckling analysis will stop because a singularity is encountered. This can then be considered as the buckling load.

In a nonlinear buckling analysis, you use an auxiliary sweep, where a parameter for the load is increased. This type of analysis requires significantly more computing time than a linearized buckling analysis.