FRACTURES AND FAILURE MECHANICS IN LOESS AND APPLICATIONS TO ROCK MECHANICS.

Abstract

Steep cuts in loess (cohesive silt) fracture and locally fail by progressive slabbing of shell-like plates arranged concentrically around a weakened (usually wetted) zone at the toe. Each slab is bounded by tensile fractures. Unconsolidated undrained triaxial compression tests approximate actual conditions. Careful mapping of fracture surface features has revealed how the failures progress from point to point. The dominance of hackle marks over rib marks is interpreted to mean that tensile fracturing was largely ductile. Similar failures are present in other materials. Huge natural arches in rock cliffs are geometrically similar, supporting the belief that findings in loess are applicable over a wide range of scale and material type. The study has clarified certain aspects of the following processes of rock mechanics: fracture propagation, arching, subsidence, landsliding, and rockfalling. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1969
Accession Number
AD0695616

Entities

People

  • R. J. Lutton

Tags

DTIC Thesaurus Topics

  • Materials
  • Mechanics
  • Rock Mechanics

Fields of Study

  • Geology

Readers

  • Geotechnical Engineering.
  • Mechanical Engineering/Mechanics of Materials.
  • Structural Dynamics.