Accession Number : AD0695616

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

Descriptive Note : Final research rept.,

Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MISS

Personal Author(s) : Lutton,R. J.

Report Date : AUG 1969

Pagination or Media Count : 137

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)

Descriptors :   (*CONSTRUCTION, ENGINEERING GEOLOGY), (*ROCK, MECHANICAL PROPERTIES), (*SOILS, AVALANCHES), FRACTURE(MECHANICS), SILT, FAILURE(MECHANICS), TENSILE PROPERTIES, COMPRESSIVE PROPERTIES, TERRAIN, CRACKS, STRESSES, ENGINEERING GEOLOGY

Subject Categories : Geology, Geochemistry and Mineralogy
      Soil Mechanics
      Civil Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE