Accession Number : ADP204463

Title :   Stress-Strain Modeling in the Damage Regime,

Corporate Author : UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF GEOLOGICAL SCIENCES

Personal Author(s) : Sammis, Charles G.

PDF Url : ADP204463

Report Date : 14 AUG 1995

Pagination or Media Count : 5

Abstract : The micromechanical damage mechanics developed by Ashby and Sammis allows calculation of the failure surface of a brittle solid containing a known density of initial flaws of known size. However, inclusions of damage mechanics into numerical simulations of underground explosions also requires the effective elastic modulus as a function of damage. If the damage is not changed during a stress increment, then the theoretical results of O'Connell and Budianski (O&B) can be used. However, if the stress increment results in an increase in damage, then the effective elastic modulus will be lower than that given by the O&B theory due to the extra energy associated with crack propagation. Because this is a cumbersome calculation not suitable for implementation in numerical simulation codes, we have adopted the empirical approach of lowering the modulus by an additional factor during crack growth, and have evaluated this factor using stress strain data on Barre granite.

Descriptors :   *SEISMIC DETECTION, *ROCK MECHANICS, *SEISMIC WAVES, *ARMS CONTROL, *NUCLEAR EXPLOSION DETECTION, STRESS STRAIN RELATIONS, MATHEMATICAL MODELS, SYMPOSIA, SURFACE WAVES, MONITORING, DAMAGE ASSESSMENT, MODULUS OF ELASTICITY, UNDERGROUND EXPLOSIONS, CRACK PROPAGATION, BRITTLENESS, SEISMIC DISCRIMINATION, TREATIES, FAILURE(MECHANICS).

Subject Categories : Government and Political Science
      Geology, Geochemistry and Mineralogy
      Seismology
      Seismic Detection and Detectors
      Nuclear Weapons

Distribution Statement : APPROVED FOR PUBLIC RELEASE