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Title: A nonlocal strain measure for digital image correlation.


Abstract not provided.

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Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Strain, a journal in experimental mechanics
Country of Publication:
United States

Citation Formats

Lehoucq, Richard B., Reu, Phillip L., and Turner, Daniel Z. A nonlocal strain measure for digital image correlation.. United States: N. p., 2014. Web.
Lehoucq, Richard B., Reu, Phillip L., & Turner, Daniel Z. A nonlocal strain measure for digital image correlation.. United States.
Lehoucq, Richard B., Reu, Phillip L., and Turner, Daniel Z. Fri . "A nonlocal strain measure for digital image correlation.". United States. doi:.
title = {A nonlocal strain measure for digital image correlation.},
author = {Lehoucq, Richard B. and Reu, Phillip L. and Turner, Daniel Z.},
abstractNote = {Abstract not provided.},
doi = {},
journal = {Strain, a journal in experimental mechanics},
number = ,
volume = ,
place = {United States},
year = {Fri Aug 01 00:00:00 EDT 2014},
month = {Fri Aug 01 00:00:00 EDT 2014}
  • Abstract not provided.
  • Abstract not provided.
  • Graphite components, used as moderators, reflectors, and core-support structures in a High-Temperature Gas-Cooled Reactor, play an important role in the safety of the reactor. Specifically, they provide channels for the fuel elements, control rods, and coolant flow. Fracture is the main failure mode for graphite, and breaching of the above channels by crack extension will seriously threaten the safety of a reactor. In this paper, a new method based on digital image correlation (DIC) is introduced for measuring crack extension in brittle materials. Cross-correlation of the displacements measured by DIC with a step function was employed to identify the advancingmore » crack tip in a graphite beam specimen under three-point bending. The load-crack extension curve, which is required for analyzing the R-curve and tension softening behaviors, was obtained for this material. Furthermore, a sensitivity analysis of the threshold value employed for the cross-correlation parameter in the crack identification process was conducted. Finally, the results were verified using the finite element method.« less
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