Damping Evaluation Studies for Elastic and Inelastic Structural Systems Analytical and Experimental Investigations

Abstract

Structural response of the discrete linear system to dynamic loading such as wind, earthquake, impact etc. heavily depends on its dynamic properties; mass, stiffness and damping. Unlike, mass and stiffness properties which are more realistically estimated from geometry and materials of the linear system, estimation of damping is a non-trivial task, as it is resulting from coexistence of many energy dissipating mechanisms. Therefore, damping quantification and modeling attracts the attention of researchers. Advancement in the material technology and stringent serviceability and comfort requirements of flexible system keeps research work rolling related to damping. Linear viscous damping model is mostly adopted to represent the phenomenon of damping due to its mathematical simplicity as well as straight forward implementation with linear systems. Realizing that linear damping models suffer from limitations, need to develop non-linear damping models have been felt to predict, more realistically, the dynamic response of the discrete linear system. newline newline newlineNon-linear damping models like displacement squared and velocity squared have been developed and equivalent viscous damping coefficients of such models were derived using energy equivalence at steady-state response of the discrete linear system under harmonic periodic loading. However, implementation of linear and non-linear damping models with discrete linear system subjected to arbitrary excitations is a research gap. It is apparent that these non-viscous (linear and non-linear) damping models work well for a discrete linear system subjected to harmonic and non-harmonic periodic dynamic loading, where steady-state response is achieved. Damping coefficients of non-viscous damping models for a discrete linear system subjected to arbitrary dynamic loadings like step loading, impulse loading, ramp loading etc. offers challenges in its determination. Research efforts are, thus, warranted to explore methods capable of evaluating equivalent viscous damping coefficient