Triple plastic hinge mechanism for a bent cantilever beam subjected to an out-of-plane tip force pulse of finite duration

In Ref. [1], the need was demonstrated for a deformation mechanism consisting of three plastic hinges (triple-hinge mechanism) to complete the range of possible deformation modes for a bent, rigid perfectly-plastic cantilever beam subjected to a suddenly applied constant tip force applied perpendicular to the plane of the cantilever. This paper provides the analysis of the transient behaviour of such a mechanism when a rectangular force pulse (constant force applied for a finite duration) is applied to the beam. The kinematics of the various hinges are described and the partitioning, of the input energy between the five phases of the motion is evaluated.