Seismic Behavior of MFPS Isolated Structure Under Near-Fault Sources and Strong Ground Motions With Long Predominant Periods

Abstract

Base isolation, which has been recognized as a very promising way for upgrading the earthquake-proof capability of existing structures both from theoretical and experimental studies. However, some researchers suspect the efficiency of base isolator under near-fault earthquakes and strong ground motions with long predominant periods. It is suggested from previous studies that earthquakes with long predominant periods always cause severe responses of base-isolated structures. In view of this, a new base isolator called as Multiple-Friction Pendulum System (MFPS) has been proposed in this study to improve the shortcoming of those undesirable phenomenon of base-isolated structures. In order to evaluate the efficiency of MFPS isolators, the shaking table tests of a 3-story steel structure have been performed at NCREE in Taiwan. Experimental results show that the proposed isolator still posses well performance under near source excitations and strong ground motions with long period predominant periods. Therefore, the proposed base isolator can be recognized as a very promising tool for enhancing the seismic-resistance of a structure near seismic faults or on a soft deposit soil.