Nonlinear stability of a simplified model for the simulation of double suspension roofs

The present work deals with the nonlinear static as well as dynamic stability aspects of an initially imperfect dissipative 2-mass, 3–DOF model under step loading, introduced as a simplified simulation of a class of double-suspension roofs. Employing a fully nonlinear straightforward analysis it is found that global stability, being the main feature of double-suspension roofing systems, is captured by the proposed autonomous conservative model. For realistic combinations of the geometric, stiffness and damping parameters involved the model dealt with is always associated with a stable point attractor response and does not experience either snapping or large amplitude horizontal motions, contrary to recent findings reported for single suspended roof models. Finally, various mathematical and visualization obstacles were encountered, to be overcome by modern commercial software.