Effect of binonlinear hysteresis on circulatory critical loads

A binonlinear hysteretic model is proposed as the model for the restoring mechanism and energy dissipation at each of the joints of a two-degree-of-freedom circulatory system. The forward loading side and the reverse loading side of the hysteresis loop associated with the model are each composed of two cubic nonlinear line segments. The technique for applying the method of equivalent linearization to the analysis of a multi-degree-of-freedom system is developed and used. Effects of positive and negative nonlinearities in the binonlinear hysteretic restoring moments on the critical loads of the circulatory system are investigated. The results show that such nonlinearities have stabilizing and destabilizing effects in the circulatory system with either vanishing or small hysteretic damping.