Rational equivalent linear model for simple yielding systems

Abstract EN

The coneept of equivalent vi$eous damping for an elasto-plastie system is inves-tigated in this study.

An exact closed form solution of the equivalent stiffness and ،lamping is presented for sinusoidal excitation.

The exact solution is compared to five commonly used equivalent linear models.

It is argued that for harmonic exci-tation, the geometric stiffness method is an appropriate representation of the equi-valent stiffness.

For large values of ductility the associated equivalent damping ratios have little effect on the response as a result of the dominancy of the low value of the associated equivalent stiffness.