Kellerspannungsbereich

Kellerspannungsbereich refers to the range of stress levels in rock or soil where the material exhibits dilatant behavior under triaxial compression. This means that as the confining pressure increases, the volume of the material also increases. Below this range, the material is considered contractive, meaning its volume decreases under increasing confining pressure. The Kellerspannungsbereich is an important concept in geomechanics and soil mechanics, particularly in the analysis of underground excavations, tunneling, and slope stability.

The determination of the Kellerspannungsbereich is typically achieved through laboratory testing, such as triaxial compression tests. During these tests, a cylindrical sample of rock or soil is subjected to axial stress while being confined by hydrostatic pressure. By measuring the axial strain and volume change at various confining pressures, the stress at which dilatancy begins can be identified. This stress is often referred to as the dilatancy stress or critical stress.

The size and location of the Kellerspannungsbereich are influenced by several factors, including the material's properties (e.g., grain size, mineralogy, moisture content), the rate of loading, and the presence of pre-existing discontinuities or fractures. Understanding the Kellerspannungsbereich is crucial for predicting the mechanical behavior of geological materials under stress and for designing safe and stable underground structures. It helps engineers assess the potential for ground deformation, failure, and the effectiveness of support systems.