Energetic evaluation of a perfect damped elastoplastic oscillator

This paper deals with the dynamic behaviour of a perfect damped elastoplastic oscillator, subjected to an external seismic load. The rheological model is presented as a single-degree-of-freedom system, for the two cases: a symmetrical excitation (perfect elastoplasticity); and an asymmetry in the compression field. The energizing assessment is essentially established from the dissipated energy map during the oscillations, according to the structural parameters of the model (equivalent angular frequency, damping, parameter of the asymmetric excitation force…). A dissipation of the limit cycle energy observed for the alternating plasticity behavioural area, which is controlled by the bifurcation boundary.Keywords: Perfect Damped Elastoplastic Oscillator, Rheological model, Dissipated energy, Limit cycle, Alternating plasticity, Bifurcation boundary

Multi-scale energy exchanges between an elasto-plasticoscillator and a light nonsmooth system with externalpre-stress

International audienceVibratory energy exchanges between twocoupled oscillators is studied: the main elasto-plasticoscillator is coupled to a nonlinear energy sink(NES)with nonsmooth potential. Both oscillators are underpre-stressing terms. Two different methods are implementedfor tracing system behaviours: (i) the timeevent-driven technique which builds exact solutions ofgoverning equations of the system phase by phase and(ii) the multi-scale method which traces system behavioursat different scales of time. It detects invariant ofthe system at fast timescale and equilibrium/singularpoints at slow timescales. The pre-stressing terms producea more complex shape for the invariant, whiledetected dynamics at slow timescale let us have controlat the behaviour of the system during its quasi-steadystateregime(s) which leads to have analytical designtools for tuning parameters of nonlinear energy sink according to design purposes (passive control and/orenergy harvesting)