ABSTRACT
Sensor placement and control device placement have been discussed in Chapter 8 and Chapter 10, respectively. The optimal sensor locations are often determined for the purpose of structural health monitoring, such as system identification and damage detection without consideration of control performance, whereas the optimal locations of control devices always refer to control performance by assuming that structural responses, which act as feedbacks in control algorithms and indices in performance functions, can be measured by the sensors without consideration of their availability in both numbers and locations. However, it is impractical and uneconomical to install the sensors at all the required locations when full-state feedbacks are used for the control of a large civil structure. It is also not economical to install two sensory systems, one for structural health monitoring and the other one for structural vibration control, when a civil structure needs both structural health monitoring and vibration control. Therefore, for a smart civil structure, it is highly desirable to develop the techniques to locate sensors and control devices collectively and cost-effectively to give the structure self-sensing, self-adaptive and self-diagnostic ability. In this chapter, some existing collective placement methods of both sensors and control devices for civil structures are first reviewed. In terms of the response reconstruction-based sensor placement method as described in Chapter 8 and the increment-based algorithm for control device placement as introduced in Chapter 10, a collective placement method for the determination of the minimal number and optimal location of both control devices and sensors is then presented in this chapter for vibration control of building structures under earthquake excitation. The feasibility and accuracy of the proposed method are finally investigated numerically through a 20-story shear building structure under the El-Centro ground excitation and the Kobe ground excitation. The number and location of sensors and control devices determined by this collective placement method lay the foundation for the synthesis of structural health monitoring and vibration control in the time domain, which will be introduced in Chapter 15.
