Discrete-Element Model for Buckling Analysis of Thin Ring Confined Within Rigid Boundary

Abstract

An elastic ring in rigid confinement may buckle inward when pressure is applied by a uniform inward movement of the confining rigid frame, particularly when a defect or initial inward deflection is present. As a result, the buckled portion of the ring becomes free of boundary pressure. This problem is known as shrink buckling, contact buckling, or one-way buckling. This problem was investigated by using three different approaches: the discrete method, the finite-element method, and an experimental method. A discrete-element model for the stability of thin rings confined within rigid boundaries was first developed, and then the critical buckling condition was derived from equilibrium equations. The frictional effect at the interface between the ring and the boundary was then taken into consideration. A finite-element model was developed and ANSYS 4.4 was used to carry out the calculations. The results from the discrete model were compared with the results from the finite-element analysis, and finally were verified by experimental results.