Moving Hinge in Large‐Displacement Problems

Abstract

The concept of the moving‐hinge technique is discussed and compared with the classical stationary hinge approach, i.e., limit analysis, in the context of large‐displacement arch problems. With the assumption of a rigid‐perfectly plastic material and the neglect of axial and shear effects, the key equations are derived both algebraically and graphically considering a discontinuous curvature jump at the moving hinge. The problem of a circular ring crushed between two rigid plates is examined to illustrate its application. With reference to the actual deformation mode in experiments, a deformed quarter ring is modeled using three segments of arc, with two moving hinges being sandwiched in between. By using the moving hinge, a better load‐displacement curve can be obtained as opposed to conventional limit analysis, provided that the deformation mode is appropriately represented. The present three‐segment model can be further refined to include additional segments or moving hinges, thus improving predictions of the applied load from a known deformation mode.