On the inconsistency of results of standard methods of determining physical characteristics of soils

Abstract

In monitoring the strength and moisture content of soils by standard methods, the values of such characteristics as degree of saturation (saturation coefficient) S r = Wρ s /100eρ W and the density of the soil skeleton (dry-soil density) ρ d = ρ (1 + W/100) (where W is the moisture content, ρ is the density of the soil, ρ s is the density of the soil particles, e is the void ratio, and ρ W is the density of the water) are found to contradict the primordial significance of these values in a number of cases.For heavy semi-hard clays and consolidated loess soils, therefore, the values of S r have exceeded unity and attained 1.17-1.21 in laboratory tests, while ρ d has been found to be greater than ρ d,max , as determined in accordance with GOST 30416-96(1)Here, V a is the volume of the air entrapped in the soil at its maximum density (V a = 0.035 when I p ranges from 4 to 12%, and V a = 0.045 when I p > 12%).The formula for degree of saturationis obtained from (1), where n min is the porosity corresponding to ρ d,max from (1), which has made it possible to compare S r,max obtained from (2) with standard formulas, is obtained from (1). S r,max = 0.87-0.91