BEHAVIOR OF UNSATURATED SOIL AND ITS INFLUENCE ON SOIL - SOIL INTERACTION AT AN INTERFACE.

Persistent Link:
http://hdl.handle.net/10150/184224
Title:
BEHAVIOR OF UNSATURATED SOIL AND ITS INFLUENCE ON SOIL - SOIL INTERACTION AT AN INTERFACE.
Author:
TOUFIGH, MOHAMMAD MOHSEN.
Issue Date:
1987
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The interface failure between caps and natural soil in trenches containing buried low level nuclear waste material was investigated in this study. The Casa Grande Highway Farm (CGHF) soil was used for the entire investigation. This soil is described as being a silty sand with approximately 23% by weight passing sieve No. 200. Other preliminary testing was performed on the same soil. Isotropically consolidated drained (CID) tests were performed on the laboratory compacted samples at different degree of saturation including fully saturated specimens. Suction pressure was measured in the laboratory by adopting pressure plate extractor and compared with determined effective suction in triaxial testing. A generalized failure equation, in term of strength parameters and suction pressure, was defined for all degrees of saturation. The consideration of unsaturated soil sets the current modified model apart from previous bounding surface which only allows use of fully saturated cohesive soil. The saturated material constants associated with the model are identified. These new constants are obtained from a generalized failure equation. The model was then verified by comparing predictions with other laboratory tests which are not used in the calibration. Generally a good agreement between the model and test results was found for stress-strain, stress path and volumetric strain response at different degrees of saturation. Extensive interface tests were performed in the conventional direct shear machine with some modification. Similar to trench cap soil and natural soil in the field, the test specimens were prepared at different degrees of saturation and density (compaction effort). Comparisons were made for the effects of magnitude of normal load, degree of saturation, density, compaction effort, moisture migration and dissimilar bodies density. An interface element and the modified bounding surface model and elasticity model was used in a finite element program to predict the interface response for the laboratory results and actual field problems. Material parameters related to the interface were identified and good predictions were observed for the interface behavior.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Soil dynamics.; Soils -- Plastic properties.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Civil Engineering and Engineering Mechanics; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Nowatzki, Edward A.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleBEHAVIOR OF UNSATURATED SOIL AND ITS INFLUENCE ON SOIL - SOIL INTERACTION AT AN INTERFACE.en_US
dc.creatorTOUFIGH, MOHAMMAD MOHSEN.en_US
dc.contributor.authorTOUFIGH, MOHAMMAD MOHSEN.en_US
dc.date.issued1987en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe interface failure between caps and natural soil in trenches containing buried low level nuclear waste material was investigated in this study. The Casa Grande Highway Farm (CGHF) soil was used for the entire investigation. This soil is described as being a silty sand with approximately 23% by weight passing sieve No. 200. Other preliminary testing was performed on the same soil. Isotropically consolidated drained (CID) tests were performed on the laboratory compacted samples at different degree of saturation including fully saturated specimens. Suction pressure was measured in the laboratory by adopting pressure plate extractor and compared with determined effective suction in triaxial testing. A generalized failure equation, in term of strength parameters and suction pressure, was defined for all degrees of saturation. The consideration of unsaturated soil sets the current modified model apart from previous bounding surface which only allows use of fully saturated cohesive soil. The saturated material constants associated with the model are identified. These new constants are obtained from a generalized failure equation. The model was then verified by comparing predictions with other laboratory tests which are not used in the calibration. Generally a good agreement between the model and test results was found for stress-strain, stress path and volumetric strain response at different degrees of saturation. Extensive interface tests were performed in the conventional direct shear machine with some modification. Similar to trench cap soil and natural soil in the field, the test specimens were prepared at different degrees of saturation and density (compaction effort). Comparisons were made for the effects of magnitude of normal load, degree of saturation, density, compaction effort, moisture migration and dissimilar bodies density. An interface element and the modified bounding surface model and elasticity model was used in a finite element program to predict the interface response for the laboratory results and actual field problems. Material parameters related to the interface were identified and good predictions were observed for the interface behavior.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectSoil dynamics.en_US
dc.subjectSoils -- Plastic properties.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineCivil Engineering and Engineering Mechanicsen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorNowatzki, Edward A.en_US
dc.contributor.committeememberJimenez, R. A.en_US
dc.contributor.committeememberContractor, D. N.en_US
dc.contributor.committeememberKundu, T.en_US
dc.contributor.committeememberRichard R. M.en_US
dc.identifier.proquest8727939en_US
dc.identifier.oclc699825751en_US
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