Drying Soil-Water Characteristic Curve (SWCC)

Previous pageReturn to chapter overviewReturn to Top Next page












Classical soil mechanics has emphasized specific categories of soil types (e.g., saturated sands, silts, and clays and dry sands). Research has focused on the development of theories related to these broad categories of soils. The soils are usually assumed to be in either a completely dry or a completely saturated condition. However, many soils do not fall into these common categories. A large portion of soils found in-situ can be classified as unsaturated soils. Unsaturated soils have often been avoided in engineering practice due to the complexity associated with understanding their physical behavior. Central to the behavior of an unsaturated soil is the relationship between the amount of water and air in the soil. This relationship is described by the Soil-Water Characteristic Curve (SWCC). Laboratory studies have shown that there is a relationship between the soil-water characteristic curve and the properties of an unsaturated soil (Fredlund and Rahardjo, 1993b).


Initial State: Initial State fields calculate the theoretical initial state of the soil based on in-situ volume-mass properties. It is assumed that the soil, previously at its in-situ state, has been exposed to water and allowed to swell and become saturated for laboratory testing purposes. The theoretical initial state of the soil-water characteristic curve soil sample is therefore calculated according to input volume-mass values.


Fitting Method: The Fitting Method drop list contains all the methods currently implemented in SVSOILS for the fitting of laboratory data using mathematical equations. A description of these methods can be found in the SVSOILS Theory Manual.


Shrinkage volume change: Check the Shrinkage volume change checkbox to enable shrinkage properties.


Related links (Topics relating to this section):


SWCC - Fit Methods

Volume-Mass State