Table 3.

Site classifications scheme according to Pitilakis et al. (2018)

Site class	T0	VS (m/s)	Thickness	Description
A	≤ 0.2 s	VS30 or ≥ 800	Surface weathered layer H < 5 m	Seismic bedrock
B1	0.1–0.3 s	$V_{s,avg}$: 350–600 VS,30: 400–760	H < 30 m	Very dense sand and/or stiff clay
B2	0.3–0.6 s	$V_{S,avg}$: 400–550 VS,30: 350–500	30 m < H < 120 m
C1	0.6–1.0 s	$V_{S,avg}$: 400–600 VS,30: 350–450	H > 60 m	Medium dense sand and/or stiff clay
C2	0.3–0.7 s	$V_{S,avg}$: 250–450 VS30: 250–400	20 m < H < 60 m
C3	0.7–1.4 s	$V_{S,avg}$: 300–500 VS,30: 200–350	H > 60 m
D	≤ 1.4 s	$V_{S,avg}$: 200–400 VS,30: 150–300		Soft soil
E	0.1–0.5 s	$V_{S,avg}$: 160–300	5 m < H < 20 m	Soft soils overlaying rock (or site class A)
X	Special soils requiring site-specific evaluations ($V_{S,avg}$ < 160 m/s)