An equivalent approach for modelling butterfly-hysteresis passive variable friction damper

Abstract

Abstract This research work proposes an equivalent approach modelling the peculiar hysteretic behavior of passive variable friction damper, for engineers who call for a simplified way to simulate such damper in anti-earthquake engineering practice with acceptable accuracy. This approach models the special nonlinear behavior of the damper via paralleling 3 basic link elements that commonly built-in commercially available structural analysis software, instead of developing direct hysteretic model that demands for both post development functionality on software side and programming skill on engineer side. The mathematical derivation and analytical geometric equating work are comprehensively conducted. The numerical accuracy of analysis output yielded using equivalent model is digitally verified against the one yielded using generic FEM simulation of the same damper subject to several loading cases. Code-automated optimization workflow for yielding product-wise modelling parameters is developed that is convenient and straightforward for application by engineers without requirement of high expertise, which is demonstrated by generating optimized parameters to equivalently model tested specimen. Article highlights Passive variable friction damper can be modelled by assembling friction spring, elastic spring and wen model into parallel. Code-automated optimization process can locate the most ideal modelling parameters combination in predefined numeral fields. Hysteretic behaviors yielded from equivalent modelling approach match well corresponding ones from generic FEA simulation.