Effects of Dwell Time and Loading Rate on the Nanoindentation Behavior of Asphaltic Materials
In a nanoindentation test, a test sample is indented or loaded by an intender tip and then unloaded, and the load-displacement data are recorded. Load-displacement data are then analyzed using a common method to determine elastic modulus and hardness of materials. The slope of the unloading curve is positive and typically follows the slope of the loading curve for hard samples such as aluminum and silicon. The analysis method is not applicable if the unloading curve follows a negative slope, which is the case for soft viscous materials, such as asphalt binders and polymers. However, past studies have not attempted to examine the effects of dwell time and loading rate on viscous materials, such as asphalt binders, which are performed in this study. It is shown in this paper that an increase in dwell time shows a decrease in the bowing out or nose effect of the unloading portion of the load-displacement curve. At very low loading rates, asphalt binder shows a high viscous effect, which creates a large negative slope of the unloading curve.
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Availability:
- Find a library where document is available. Order URL: http://worldcat.org/issn/21535434
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Supplemental Notes:
- Copyright © 2013 American Society of Civil Engineers
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Authors:
- Tarefder, Rafiqul A
- Faisal, Hasan
- Publication Date: 2013-6
Language
- English
Media Info
- Media Type: Digital/other
- Features: References;
- Pagination: pp 17-23
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Serial:
- Journal of Nanomechanics and Micromechanics
- Volume: 3
- Issue Number: 2
- Publisher: American Society of Civil Engineers
- ISSN: 2153-5434
- Serial URL: http://ascelibrary.org/toc/jnmoco/4/1
Subject/Index Terms
- TRT Terms: Dwell time; Hardness; Load factor; Modulus of elasticity; Nanotechnology; Polymers; Viscoelasticity
- Subject Areas: Highways; Materials; I30: Materials;
Filing Info
- Accession Number: 01482016
- Record Type: Publication
- Files: TRIS, ASCE
- Created Date: May 22 2013 1:07PM