Definition of Terms Fluid Mechanics and Hydraulics
Definition of Terms Fluid Mechanics and Hydraulics
Soil Properties
Void Ratio - The ratio of the volume of void space to the volume of solid substance.
Porosity - The ratio of the volume of voids to the volume of the soil sample or specimen. It is simply the open space between the soil grains.
Degree of Saturation - The ratio of the volume of water in the void spaces to the volume of the voids. It is simply the measure of the void volume that is filled by water, expressed as a percentage ranging from zero to one hundred.
Moisture Content - The ratio of weight of water to the weight of solids in a given volume of soil.
Unit Weight - the weight of soil per unit volume
Dry Unit Weight - the weight per unit volume of soil, excluding water
Saturated Unit Weight - the bulk unit weight of a soil when it is one hundred percent saturated.
Bulk unit weight - known as total, wet or moist unit weight. It is the total weight divided by the total volume
Critical hydraulic gradient - the hydraulic gradient that brings a soil (essentially, Coarse-grained soils) to static liquefaction
Density - The ratio of the total mass to the total volume of a unit of soil. Usually expressed as a unit weight where weight is interchanged with mass.
Dry density - The ratio of the mass of the solids (soil grains) to the total unit volume of soil.
Submerged Density - Also, buoyant density. Difference between the total density and the density of water
Density index -Also, relative density. The density of a granular soil relative to the minimum and maximum densities achieved for that particular soil
Atterberg Limits
Atterberg Limits
Consistency - used to describe the degree of firmness of soil
Cohesion - the attraction of one water molecule to another resulting from hydrogen bonding (water-water bond).
Adhesion - It involves the attraction of a water molecule to a non-water molecule (water-solid bond).
Stickiness - The capacity of soil to adhere to other objects. It is estimated at moisture content that displays maximum adherence between thumb and forefinger.
Rupture Resistance - a field measure of the ability of the soil to withstand an applied stress or pressure as applied using the thumb and forefinger.