Authors: Mazhar A. Dhankot; Devesh P. Soni
Addresses: School of Engineering, R.K. University, India; Civil Engineering Department, Marwadi Education Foundations Group of Institutions, Rajkot-360003, India ' Civil Engineering Department, Sardar Vallabhbhai Patel Institute of Technology, Vasad-388306, Gujarat, India
Abstract: Triple friction pendulum (TFP) bearing is a new generation sliding isolation system having multiple spherical sliding surfaces. The friction isolation system with single sliding surface is designed for a specific level of ground shaking, which may prove ineffective in case of other hazard levels. The TFP bearing on the other hand, exhibits adaptive behaviour and imparts greater amount of flexibility to the designer for various levels of earthquake shaking. Herein seismic response of TFP bearing is studied under 60 records comprising of service level, design basis and maximum considered earthquakes. Two types of surfaces having low and high friction in combination with three different displacement capacities of the bearing, resulting in six isolator design are considered. It is shown that although being a passive device, the TFP bearing stiffens at low input shaking, softens with increasing input reaching a minimum at the DBE, and then stiffens again at higher levels of input and thereby shows adaptive behaviour. Further, the increase of displacement capacity of bearing influences the response under MCE event, however, for DBE and SLE no significant change in demand is observed.
Keywords: triple friction pendulum; TFP bearings; adaptive behaviour; multi hazard levels; seismic performance; MDOF system; earthquakes; seismic response; sliding isolation systems; friction isolation; displacement capacity.
International Journal of Structural Engineering, 2016 Vol.7 No.4, pp.412 - 431
Received: 13 Aug 2015
Accepted: 27 Oct 2015
Published online: 16 Sep 2016 *