Hardening vs. softening dichotomy of a hinged-simply supported beam with one end axial linear spring: Experimental and numerical studies

The aim of this paper is to validate experimentally a nonlinear model of a kinematically excited hinged-simply supported beam with a spring subjected to one end. An experimental setup configuration enables to test different variants of axial boundary conditions: first a typical simply supported beam (no spring), and next two different spring systems. The prototype is kinematically excited with different amplitudes of excitation and then full frequency response curves are drawn wherein hardening/softening dichotomy is recognized. A set of mechanical properties of the system is identified and then used to reproduce tests with finite element simulations. Consequently numerical vs. experiment results are compared. The analysis demonstrates amplitude dependent damping as well as that the natural frequency depends on environmental conditions, and thus may change over experiments.