TABLE OF CONTENTS Basic soil properties and parameters can be subdivided into physical, index, and engineering categories. Physical soil properties include density, particle size and distribution, specific gravity, and water content.
The water content w of a soil sample represents the weight of free water contained in the sample expressed as a percentage of its dry weight.
The degree of saturation S of the sample is the ratio, expressed as percentage, of the volume of free water contained in a sample to its total volume of voids V v.
Porosity n, which is a measure of the relative amount of voids, is the ratio of void volume to the total volume V of soil:
| (8.1) |  |
The ratio of V v to the volume occupied by the soil particles V s defines the void ratio e. Given e, the degree of saturation may be computed from
| (8.2) |  |
where G s represents the specific gravity of the soil particles. For most inorganic soils, G s is usually in the range of 2.67 0.05.
The dry unit weight ? d of a soil specimen with any degree of saturation may be calculated from
| (8.3) |  |
where ? w is the unit weight of water and is usually taken as 62.4 lb/ft 3 (1001 kg/m 3) for freshwater and 64.0 lb/ft 3 (1026.7 kg/m 3) for seawater.
Index parameters of cohesive soils...
