Relative Density is the ratio of the density of a substance to a specified reference density. $latex D_r = \frac{\rho_s}{\rho_{ref}}&s=2$ Where: Dr = Relative Density (dimensionless) ρs = bulk density of soil (kg/m3 or lb/ft3) ρref = bulk density of reference (kg/m3 or lb/ft3) Often, the reference density is that of water, 62.4 lbs/ft3 or […]