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Table 2 Site classification based on Vs30 (National Earthquake Hazard Reduction Provision, 1998)

From: Seismic hazard microzonation of Bengkulu City, Indonesia

NEHRP
Site Class
General Description Range of Vs30
[m/s]
A Hard Rock Vs30 > 1500
B Rock 760 ≤ Vs30 ≤ 1500
C Very Dense Soil and Soft Rock 360 ≤ Vs30 ≤ 760
D Stiff Soil [15 ≤ N ≤ 50 or 50 kPa ≤ N ≤ 100 kPa] 180 ≤ Vs30 ≤ 360
E Soil or any profile with more than 3 soft clay defiled as soil with PI > 20, w ≥ 40%, and su < 25 kPa Vs30 < 180
F Soils requiring site-specific evaluation
  1. Remarks: N = SPT value [blows/ft], su undrained shear strength, PI plasticity index, w water content