Nano and Neutron Science Applications for Geomechanics

다국어 초록 (Multilingual Abstract)

Recent advances in experimental characterization techniques offer unique opportunities to evaluate mechanical properties of
geomaterials. In this paper, authors introduce two such techniques that have significant potential to impact geomechanics community.
The technique of using Instrumented indentation testing using nano-indenter to evaluate hardness and modulus of individual sand
particles is introduced. Use of the measured data from nanoindenter on individual sand grain in modelling its assembly using
numerical methods such as the discrete element method (for example PFC-2D) is addressed. Modulus for two silica sands with
varying particle shape is presented for the depth of indentation in the range of 100 to 1000 nanometers. Use of neutron science for
solving relevant problems to geotechnical engineering is also described in this paper. Neutrons are subatomic particles with no
electric charge having duality and interacts with atomic nuclei, while X-ray interacts with electrons. Neutrons thus have significantly
higher penetration power for most geo-materials when compared to X-rays and are sensitive to hydrogen. Use of neutrons for solving
a new class of problems including non-destructive evaluation of strain at particle level while the assemblage is subjected to target
stress conditions, and imaging applications including flow through partially saturated porous medium are presented.

다국어 초록 (Multilingual Abstract)

Recent advances in experimental characterization techniques offer unique opportunities to evaluate mechanical properties of
geomaterials. In this paper, authors introduce two such techniques that have significant potential to impact geomechanics community.
The technique of using Instrumented indentation testing using nano-indenter to evaluate hardness and modulus of individual sand
particles is introduced. Use of the measured data from nanoindenter on individual sand grain in modelling its assembly using
numerical methods such as the discrete element method (for example PFC-2D) is addressed. Modulus for two silica sands with
varying particle shape is presented for the depth of indentation in the range of 100 to 1000 nanometers. Use of neutron science for
solving relevant problems to geotechnical engineering is also described in this paper. Neutrons are subatomic particles with no
electric charge having duality and interacts with atomic nuclei, while X-ray interacts with electrons. Neutrons thus have significantly
higher penetration power for most geo-materials when compared to X-rays and are sensitive to hydrogen. Use of neutrons for solving
a new class of problems including non-destructive evaluation of strain at particle level while the assemblage is subjected to target
stress conditions, and imaging applications including flow through partially saturated porous medium are presented.

참고문헌 (Reference)

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