Research on Nonlinear Buckling and Critical Loads of Horizontal Constrained Circular Rod Affected by Friction

The buckling behavior of a rod constrained by a horizontal wellbore under axial compressive load is significantly influenced by friction, and predicting the critical loads accurately is crucial for engineering safety. In this paper, a mechanical model of the rod buckling based on definitions of initial defects is established. A finite element solution methodology is proposed by utilizing the transient dynamics method, and the influence mechanism of friction on the buckling behavior in the presence of initial defects is analyzed systematically. The dominant factors affection the buckling behavior and critical load of rods are presented when the friction is considered. The influence trend of initial defects on sinusoidal and helical buckling is analyzed quantitatively, upon which it is determined that the critical loads of the rod is predominantly influenced by tangential friction. It was found that the effect of tangential friction on the critical load of the rod in the literatures was underestimated.