Related Experiment Video
Updated: May 11, 2026
10:06
Characterization Of Multi-layered Fish Scales (Atractosteus spatula) Using Nanoindentation, X-ray CT, FTIR, and SEM
Published on: July 10, 2014
Explanation for fracture spacing in layered materials
1Department of Geological and Environmental Sciences, Stanford University, California 94305-2115, USA. bai@pangea.stanford.edu
Nature
|February 29, 2000
Summary
Fracture spacing in layered materials initially decreases with strain but then stabilizes, a phenomenon termed fracture saturation. This study reveals the underlying stress transitions causing this saturation, contrasting with prior theories.
Area of Science:
- Geomechanics
- Materials Science
- Rock Physics
Background:
- Layered materials exhibit fracture spacing proportional to layer thickness.
- Existing fracture theories do not fully explain fracture saturation.
- Fracture saturation occurs when new fractures cease forming and existing ones widen.
Purpose of the Study:
- Investigate the full stress distribution between fractures in layered materials.
- Develop a physical model for fracture saturation.
- Explain the transition from tensile to compressive stress between fractures.
Main Methods:
- Numerical simulations
- Laboratory experiments
- Analysis of stress distribution
Main Results:
- Observed a transition from tensile to compressive normal stress between fractures with increasing applied stress.
- Demonstrated that fracture spacing scales with layer thickness after saturation.
- Developed a physical model explaining fracture saturation.
Conclusions:
- The transition in normal stress is the cause of fracture saturation.
- The derived physical model provides an intuitive understanding of fracture saturation.
- The findings have broad applications in geosciences and engineering.
Related Concept Videos
02:37Metallic Solids
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
02:18X-ray Crystallography
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
01:09Spongy Bone
All bones comprise an outer layer of compact bone, and an interior made up of spongy bone tissue, also called cancellous or trabecular bone. In long bones, spongy bone tissue is mainly found in the interior of the epiphyses (broad ends of the bone).
Spongy bone is more porous, and less dense compared to compact bone. It is composed of concentric lamellae that are arranged irregularly to form the trabecular network. In some bones, the spaces between trabeculae contain red marrow, where...
Spongy bone is more porous, and less dense compared to compact bone. It is composed of concentric lamellae that are arranged irregularly to form the trabecular network. In some bones, the spaces between trabeculae contain red marrow, where...
01:24Stress-Strain Diagram - Brittle Materials
Brittle materials, including glass, cast iron, and stone, exhibit unique characteristics. They fracture without considerable change in their elongation rate, indicating that their breaking and ultimate strength are equivalent. Such materials also show lower strain levels at the point of rupture. The failure in brittle materials predominantly results from normal stresses, as evidenced by the rupture created along a surface perpendicular to the applied load. These materials do not display...
01:15Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
01:11Bending of Members Made of Several Materials
In analyzing a structural member composed of two different materials with identical cross-sectional areas, it is crucial to understand how their distinct elastic properties affect the member's response under load. The analysis involves assessing stress and strain distributions using the transformed section concept, which accounts for variations in material properties.
Hooke's Law determines stress in each material, stating that stress is proportional to strain but varies due to each material's...
Hooke's Law determines stress in each material, stating that stress is proportional to strain but varies due to each material's...