Experimental Investigations of the Seismic Performance of a Base-Isolated Uninterruptible Power Supply (UPS) through Shaking Table Tests

Table 1

Detailed characteristics of an isolator system used in this study.

Stories	Type	Features	Mechanical properties
First story	Laminated rubber isolator	Diameter of rubber: 50 mm	Shear modulus: 0.4 MPa; Prestress surface pressure: 6 MPa; Horizontal stiffness : 530.1 N/mm; Vertical stiffness : 10426.2 N/mm
		Rubber thickness: 2.5 mm
		Number of rubber sheets: 8
		Steel plate thickness: 2 mm
		Number of steel sheets: 7
Second story	Wire isolator	Wire diameter: 9.5 mm	Wire rope yield strength: 205 MPa
		Number of loops: 8	Wire rope ultimate tensile strength: 520 MPa
		Width of a loop: 80 mm	Horizontal stiffness : 93.4 N/mm
		Length of retainer: 170 mm	Vertical stiffness : 2329.8 N/mm