Dynamic Response of a Combined Isolation Based Mega-Substructure under Bidirectional Near-Fault Ground Motions

Table 8

Main frame base shear response and damping rate (kN).

Test cases	Earthquake	Direction	Input amplitude	Aseismic	Combined isolation	Damping rate
S1	Chi-Chi-2N	Y	0.056 g	3.44	2.03	40.99%
S2	Chi-Chi-2F	Y	0.056 g	2.86	1.76	38.46%
B1	Chi-Chi-2N	X	0.051 g	3.48	1.98	43.10%
		Y	0.056 g	3.62	2.07	42.82%
B2	Chi-Chi-2F	X	0.051 g	2.97	1.76	40.74%
		Y	0.056 g	3.11	1.87	39.87%
S3	Chi-Chi-2N	Y	0.153 g	9.38	5.83	37.85%
S4	Chi-Chi-2F	Y	0.153 g	8.14	5.02	38.33%
S5	Chi-Chi-3N	Y	0.153 g	11.46	6.84	40.31%
B3	Chi-Chi-2N	X	0.140 g	9.12	5.61	38.49%
		Y	0.153 g	9.87	6.12	37.99%
B4	Chi-Chi-2F	X	0.139 g	8.01	4.87	39.20%
		Y	0.153 g	8.64	5.31	38.54%
B5	Chi-Chi-3N	X	0.113 g	11.16	6.69	40.05%
		Y	0.153 g	12.13	7.24	40.31%
S6	Chi-Chi-2N	Y	0.316 g	16.42	9.98	39.22%
S7	Chi-Chi-2F	Y	0.316 g	14.15	8.69	38.59%
S8	Chi-Chi-3N	Y	0.316 g	18.49	11.87	35.80%
B6	Chi-Chi-2N	X	0.289 g	16.91	10.4	38.50%
		Y	0.316 g	17.43	10.7	38.61%
B7	Chi-Chi-2F	X	0.288 g	14.67	9.84	32.92%
		Y	0.316 g	14.88	9.75	34.48%
B8	Chi-Chi-3N	X	0.297 g	19.69	11.75	40.33%
		Y	0.316 g	19.96	11.98	39.98%