Fuzzy Control for Seismic Protection of Semiactive Base-Isolated Structures Subjected to Near-Fault Earthquakes

Abstract

This paper proposes a new fuzzy logic controller, which is designed for seismic protection of base-isolated structures utilizing piezoelectric friction damper against near-fault earthquakes for different ground sites. According to the elastic design spectrum that Eurocode 8 recommends, one 5% damped elastic design spectrum for Chi-Chi earthquake is proposed to generate artificial earthquakes of different ground sites. The proposed controller employs a hierarchic fuzzy control algorithm, in which a supervisory fuzzy controller governs a sublevel fuzzy controller by altering its input normalization factors according to current level of ground motion. In order to simultaneously reduce the base displacement and superstructure responses of the base-isolated structure during seismic excitations, genetic algorithm is employed to optimize the supervisory fuzzy controller and the preload of piezoelectric friction damper. The efficiency of the proposed controller is also compared with passive controller and a linear quadratic Gauss optimal controller. Numerical results show that the proposed fuzzy logic controller has favorable performance in mitigating the responses of the base-isolated structure.

Control of piezoelectric friction dampers in smart base-isolated structures using self-tuning and adaptive fuzzy proportional–derivative controllers

“…The results for the applied ground motions are given in Tables 6 and 7. Also, the values of the responses given by the proposed controllers are compared with those provided by other techniques, that is, maximum passive operation of PFDs, modified clipped-optimal controller (Ozbulut et al, 2011), SVFLC (Ozbulut and Hurlebaus, 2010), optimal PID controller (Etedali et al, 2013), and genetic algorithm hierarchic fuzzy logic control (GHFLC) (Zhao and Li, 2015). The results for the base-isolated building without any damper, that is, uncontrolled structure, are also given in these tables.…”

“…Etedali et al (2013) developed optimal PD or proportional–integral–derivative (PID) controllers to adjust the contact force of PFDs in an isolated structure. A hierarchic fuzzy control algorithm, in which a supervisory fuzzy controller governs a sublevel fuzzy controller by altering its input normalization factors according to current level of ground motion, was proposed by Zhao and Li (2015).…”

Sequential Ground Motion Effects on the Behavior of a Base-Isolated RCC Building

“…The isolation system has been applied to buildings [27,28], bridges [29], and other types of structures, particularly in seismic areas with high intensity, such as Japan and California, USA. The isolators have also been employed to protect primary structures and nonstructural components for nuclear power plant (NPP).…”