Design of passive energy dissipation systems based on LQR control methods

The design of passive energy dissipation systems, referred to as passive da mpers, involves the determination of the required capacity of each damper i nstalled at selected locations. Generally, dampers with an identical capaci ty are installed in various story units of a building. However, installing identical dampers in various story units does not achieve the optimal perfo rmance for the building and it may result in a conservative and more expens ive design. In this paper, two design methods, based on the concepts of lin ear quadratic regulator (LQR) control theories, are presented for the desig n of the capacity of passive dampers. For most of the passive dampers, the force applied to the structure depends only on the displacement and velocit y across the damper. From the standpoint of control theories, the passive c ontrol force depends only on the local measurements of the displacement (i. e., drift across the damper) and velocity. This type of controller is refer red to as the decentralized controller. Consequently, LQR control theories for the design of active controllers are modified and applied to the design of passive dampers. Advantages of the proposed methods for different types of passive dampers are demonstrated through numerical simulations.