Folyadékhatár

Folyadékhatár is a term used in soil mechanics and geotechnical engineering to describe the boundary or zone where the pore water pressure in a soil mass transitions from positive to negative. This phenomenon is particularly relevant in unsaturated soils, where the soil particles are not fully saturated with water. In these conditions, the forces acting between soil particles and water can create a tension or suction within the pore spaces, leading to negative pore water pressures.

The folyadékhatár marks the point at which this negative pore water pressure becomes significant. Below this boundary, the soil is considered saturated and pore water pressures are typically positive or zero. Above the folyadékhatár, the soil is unsaturated, and negative pore water pressures dominate, contributing to the effective stress and the strength of the soil.

Understanding the folyadékhatár is crucial for analyzing the behavior of soils under various conditions, including slope stability, foundation design, and the impact of environmental changes such as drought or rainfall. The precise location and nature of the folyadékhatár can be influenced by factors like soil type, particle size distribution, and the degree of saturation. Measurements of soil moisture content and pore water pressure are often used to identify and characterize this important transition zone.