Seismic Pulse Broadening Associated with Fracture Damage Caused by Explosions in Crystalline Rock

Abstract

Recent analyses of the initiation, propagation, and linkage of fractures from pre-existing cracks have been used to formulate a damage mechanics for brittle solids loaded in compression. The model describes the accumulation of damage with strain. It has been used to construct damage initiation surfaces and failure surfaces which have been tested using previously published experimental data. It is shown that a damage mechanics rheology can produce seismic pulse-broadening observed in underground tests in granitic rock. It is proposed that the basic scaling relation between the size of the pre-existing cracks and the stress required to initiate damage may explain why models based on laboratory data and large scale laboratory simulations have failed to reproduce the pulse-broadening observed in the field.

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Document Details

Document Type
Technical Report
Publication Date
Aug 30, 1989
Accession Number
ADA216135

Entities

People

  • Charles G. Sammis

Organizations

  • University of Southern California

Tags

Communities of Interest

  • Air Platforms
  • C4I

DTIC Thesaurus Topics

  • Air Force
  • Earth Sciences
  • Elastic Properties
  • Failure Mode And Effect Analysis
  • Geography
  • Geology
  • Geophysics
  • Materials
  • Mechanical Properties
  • Mechanics
  • Planetary Sciences
  • Stress Concentration
  • Stress Strain Relations
  • Stresses
  • Three Dimensional
  • Two Dimensional
  • United States

Readers

  • Geotechnical Engineering.
  • Materials Science (Mechanical Engineering).
  • Structural Health Monitoring of Composite Structures.