Modeling of a full-scale MR damper and its application in open-loop vibration control of stay cables

摘要

A parameter-adaptive three-element model is first developed for a full-scale MR damper based on laboratory tests. The parameters of the model are represented by a set of empirical formulae in terms of displacement amplitude, voltage input, and excitation frequency. The model is then incorporated into the governing equation of cable-damper system for investigation of open-loop vibration control of stay cables in a cable-stayed bridge, by installing the dampers in single-and twin-damper setups respectively. The concept of optimal voltage/current input achieving the maximum damping for the system is put forward and verified. Multi-mode and multi-switch open-loop control methods in single- and twin-damper setups are then developed and a procedure for determining optimal geometric configuration of the twin-damper setup is proposed. The developed analytical formulations and design methods contribute to consummating the design specifications/guidelines for open-loop cable vibration control using MR dampers.