Effects of Soil-Structure Interaction on Torsionally Coupled Base Isolated Machine Foundation under Earthquake Load

Table 3

Peak deck acceleration and displacement obtained from the FE analysis of the nonisolated machine foundation.

Case		Peak deck acceleration, ()		Peak deck displacement, uy (mm)		Peak deck displacement, ux (mm)
		Without SSI	With SSI	Without SSI	With SSI	Without SSI	With SSI
Imperial Valley, array #5, 1979
Torsionally uncoupled		1.19	3.31	28.26	138.54	0	0
Torsionally coupled	er = 0.05	1.36	3.21	35.63	142.69	1.60	5.31
	er = 0.15	1.63	2.80	54.06	141.92	6.15	16.25
Northridge, 1994
Torsionally uncoupled		2.39	4.84	56.35	189.12	0	0
Torsionally coupled	er = 0.05	2.60	4.67	67.80	188.24	2.99	8.22
	er = 0.15	2.73	3.99	89.03	174.78	10.58	24.67
Kobe, 1995
Torsionally uncoupled		2.04	5.41	48.58	220.71	0	0
Torsionally coupled	er = 0.05	2.50	5.40	64.65	236.42	2.96	8.82
	er = 0.15	3.25	4.32	106.30	263.25	12.47	20.75