Abstract: “In this paper, a one-dimensional (1d) parallel model able to simulate the horizontal dynamic behavior of Helical Wire Rope Isolators (HWRIs) in both Roll and Shear directions is proposed. The experimental tests performed on a HWRI, manufactured by Powerflex S.r.l. (Limatola, Italy), are first presented in order to describe the dynamic response of the tested metal device at different displacement amplitudes without and under the effect of the vertical load. The parallel modeling concept has been applied to discretize an exponential function proposed to reproduce the variation of the horizontal tangent stiffness at both small and large displacements, thus allowing to simulate the dynamic behavior of such devices by putting in parallel a purely linear elastic element, and a sufficiently high number of simple elastic-perfectly plastic elements and linear elastic gap elements. The mathematical model, requiring the evaluation of only five parameters from experimental data, has been validated”

Keywords: helical wire rope isolators, nonlinear dynamic analysis, parallel modeling, seismically base-isolated structures