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Initiation and Propagation of Bond Cracks as Detected by Laser Holography and Acoustic Emission

Published online by Cambridge University Press:  21 February 2011

Arup Maji
Affiliation:
Department of Civil Engineering, Northwestern University, Evanston, Illinois
S. P. Shah
Affiliation:
Department of Civil Engineering, Northwestern University, Evanston, Illinois 60201.
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Abstract

Interfaces between hardened portland cement matrix and aggregates are considered relatively weak and a source of microcrack initiation. Based on optical and scanning electron microscopic studies of fractured concrete specimens, researchers have studied the role of interface in the fracture mechanism of cement composites. Acoustic Emission source location technique and laser holography provide noninvasive and nondestructive tools to study microcracking as well as the pertinent displacement field associated with cracking. In this paper, some results obtained using laser holography, speckle methods and acoustic emission source loction measurements for model concrete specimens containing circular aggregate inclusions are described. Effects of diameter of circular inclusions on mode of cracking are reported.

Type
Research Article
Copyright
Copyright © Materials Research Society 1988

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References

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