Comparative study on damping models of linear system subjected to arbitrary dynamic loading

Abstract

Linear and nonlinear damping models, correlated through equivalent damping coefficient, have been developed for discrete vibrating system employing energy equivalence principle at steady state response of the system. Application of, so developed, damping models to derive response of discrete vibrating system subjected to arbitrary dynamic loading is not obvious due to transient nature of the system. Thus, the equivalent damping coefficient of damping models needs to be redefined to derive realistic transient response of the system. In the present study, first cycle damping coefficient (FCDC) approach is proposed that uses the first cycle transient response of the system to derive equivalent damping coefficient for linear and nonlinear damping models through genetic algorithm propelled energy equivalence with that of linear viscous damping model. A single degree of freedom (SDOF) system with linear and nonlinear damping models subjected to arbitrary dynamic loading are solved. Efficacy of proposed FCDC approach is established through the experimental study on a lightly damped single storey building model. Velocity squared damping model yields higher peak displacement response for the system vis-a-vis system with linear viscous damping model. Proposed FCDC approach can be effectively utilised if the transient response of the system is available experimentally.