Affiliation:
1. University Politehnica of Bucharest, Romania
Abstract
In the light of recent technological advances, semi-active structural damping systems for seismic vibration mitigation are considered part of the civil engineering design process. Various actuating devices have been integrated into structures along with specifically designed control strategies. Semi-active dampers are nonlinear switching systems that require enhanced controllers. In order to minimize instability risk, a cascaded fuzzy control system that integrates the switch behaviour is designed. The inner loop uses a PI (proportional-integral) controller that is tuned with evolutionary optimization. The case study uses an electrohydraulic damper and a three-story building. To anticipate robustness to real-world disturbances and equipment failure, an uncertainty effect analysis is included in which three control systems are compared. First, structural and actuator disturbances are considered. Then, the case of switch failure brings forth the high reliability of the fuzzy control system, in what concerns using semi-active dampers in the development of civil structures.