Complementarity, duality and symmetry in nonlinear mechanics: A ROBUST VARIATIONAL FORMULATION FOR A ROD SUBJECT TO INEQUALITY CONSTRAINTS

摘要

We present a variational formulation of a constrained rod using soft wall contact. Care is taken to formulate a computationally robust method. The method is applied to a simple model for a drill string. Special boundary conditions are considered which allow the results to be compared with known (planar) results in the literature. The agreement is found to be good. An interesting dependence of the post-buckling behaviour on the boundary conditions is found. Finally, some 3D post-buckling solutions are computed as well.