ABSTRACT
This chapter provides an introduction to the control devices used in civil structures with reference to the excellent book written by Cheng et al. It discusses the basic principle and characteristics of each type of device. Control devices are responsible for moving or controlling a civil structure. Control devices include not only the actuators operated by a source of energy but also the dampers operated without external energy. Seismic base isolation is a technique that mitigates the effects of an earthquake using a flexible base composed of a specific material with low lateral stiffness that filters out the energy of high frequencies from potentially dangerous ground motion. The concept of modern seismic base isolation emerged in the early 1970s, but the design and construction of base-isolated buildings increased exponentially until the late 1980s. Natural rubber was initially used for the fabrication of elastomeric bearings. Lead-plug bearings are elastomeric-type bearings. The friction bearing was initially considered using a flat sliding surface.
