Distribution of Internal Pressure in Adsorbed Water as a Many-body 
Problem 

Masaru MlZOGUCHI* and Jyun MASUDA** 
* Faculty of Bioresources, Mie University , ** NHK Okayama 

Abstract

Internal pressure in adsorbed water has been discussed as a 
function of distance, x, from surface. Assuming adsorption 
potential for the adsorbed water is in proportional to the xb, the 
internal pressure should compensate the attractive force and 
increase toward the surface to a very high value. Two dimensional 
distribution of the internal pressure has been calculated as a many-
body problem for hypothetical soil particles by considering both the 
attractive and gravitational forces. As a result, calculated values 
simulated retention of water by soil particles. Tensiometer pressure
 estimated by the adsorption potential has been related to b value 
which represents the relationship between matric potential and 
volumetric water content in soil. In addition, deriving the influence 
of overburden pressure on internal pressure has given a theoretical 
basis for understanding solid-like stress of unfrozen water in frozen 
soil.