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Measurements of radiated elastic wave energy from dynamic tensile cracksThe role of fracture-velocity, microstructure, and fracture-energy barriers in elastic wave radiation during a dynamic fracture was investigated in experiments in which dynamic tensile cracks of two fracture cofigurations of double cantilever beam geometry were propagating in glass samples. The first, referred to as primary fracture, consisted of fractures of intact glass specimens; the second configuration, referred to as secondary fracture, consisted of a refracture of primary fracture specimens which were rebonded with an intermittent pattern of adhesive to produce variations in fracture surface energy along the crack path. For primary fracture cases, measurable elastic waves were generated in 31 percent of the 16 fracture events observed; the condition for radiation of measurable waves appears to be a local abrupt change in the fracture path direction, such as occurs when the fracture intersects a surface flaw. For secondary fractures, 100 percent of events showed measurable elastic waves; in these fractures, the ratio of radiated elastic wave energy in the measured component to fracture surface energy was 10 times greater than for primary fracture.
Document ID
19900040099
Document Type
Reprint (Version printed in journal)
Authors
Boler, Frances M. (Colorado, University Boulder, United States)
Date Acquired
August 14, 2013
Publication Date
March 10, 1990
Publication Information
Publication: Journal of Geophysical Research
Volume: 95
ISSN: 0148-0227
Subject Category
STRUCTURAL MECHANICS
Funding Number(s)
CONTRACT_GRANT: NSG-7584
Distribution Limits
Public
Copyright
Other