An Investigation on Soil Amplification through Site Factors Used in Seismic Design Codes

Table 3

Number of accounted acceleration records for the 1.0 s period (S₁) region.

Local site classes	Spectral acceleration groups
	0.05	0.10	0.20	0.30	0.40	0.50	0.60	0.70
Reference	98	196	70	42	112	182	112	56
ZB	126	252	90	54	144	234	144	72
ZC	315	630	225	135	360	585	360	180
ZD	126	252	90	54	144	234	144	72
ZE	63	126	45	27	72	117	72	36
ZF	63	126	45	27	72	117	72	36

Group not included in the codes.