Control of blast induced vibration of building by pole placement and LQG control algorithm
Keywords:
Blast load; nonstructural components; vibration control; pole allocation; structural response.Abstract
Application of smart control technology is becoming popular, particularly for a structure exposed to strong wind or seismic excitation. Although a few studies have been carried out to control blast load-induced vibrations of structures, those studies deal with passive control approach such as base isolation through laminated rubber bearings and lead rubber bearings. Past studies have demonstrated that these types of passive isolators become ineffective as they are subjected to huge displacement during strong vibration and often resulting in a permanent deformation. In these cases an effective control of vibration can be achieved by the application of active control approach as has been studied in this paper. Blast induced loading generates high frequency waves having a very short duration with a large amplitude acceleration that excites the high frequency modes of the structure during the forced regime. However, the transient part of the response is governed by the structural low frequency modes. The excitation of high frequency modes increases the peak floor acceleration of the building and thus, increases the vulnerability of the nonstructural components housed in the structure. Subsequent large displacement vibrations may further increase the damageability of such components. In this study, the pole placement algorithm is utilized to control both the displacement and acceleration responses of a four-storey building. For this purpose, a force is applied in real time through an actuator at the ground floor. The results of this study demonstrate that the proposed approach is indeed effective in controlling the responses of the structure.