Semi-active base isolation for a building structure

Abstract

Recently semi-active control methods have been proposed and received much attention. In semi-active base isolation, the coefficient of viscous damping or the spring constant is changed effectively according to the state of the control object. The system using a semi-active damper is classified as a bilinear system which belongs to non-linear systems. In this paper, optimal control theory is applied to a bilinear system using feedforward information of disturbance, and the bilinear optimal control law is derived. Then the method is applied to an actual building which is modelled by a 10 degree-of-freedom structure model with base isolation using a semi-active oil damper. The numerical analysis shows that the method has high control performance in a wide frequency range, and it is effective for the vibration base isolation of building structures.