Dilatancy correction is required when a strata is

1. Cohesive and saturated and also had N/Value of SPT > 15
2. Saturated silt/fine sand and N value of SPT < 10 after the overburden correction
3. Saturated silt/fine sand and N value of SPT > 15 after the overburden correction
4. Coarse sand under dry condition and N value of SPT < 10 after the overburden correction

n_g = 15 +	1	(N₀ - 15)
	2

N₀ - SPT value after over burden pressure correction is applied.