Semi-active structural vibration control of base-isolated buildings using magnetorheological dampers

In recent years, several solutions for structural vibration control of buildings have been proposed. In particular, the combination of base-isolated structures with complementary variable damping devices has been successful in reducing the base isolator displacements without increasing the building superstructure response when subjected to earthquake loads. In this paper, a magnetorheological device is installed on a 2-DOF mechanical model mounted on an experimental uniaxial shaking table. A simple numerical simulation model is derived for the experimental setup and it represents a typical base-isolated structure with a semi-active vibration controller. The control law combines a force tracking integral action with a clipped on–off adaptation rule that changes the magnetorheological damping in real time. The effectiveness of the proposed solution is demonstrated for both earthquake-like and real earthquake input ground motions. A comparison between the numerical and the experimental results validates the numerical simulations and it gives confidence in using this model for validation and evaluation of other semi-active control solutions based on magnetorheological dampers.