<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The study concerns soil creep deformation in multistage triaxial stress tests under drained conditions. High resolution X-ray computed microtomography (XμCT) was involved in structure recognition before and after triaxial tests. Undisturbed Neogene clay samples, which are widespread in central Poland, were used in this study. XμCT was used to identify representative sample series and informed the detection and rejection of unreliable ones. Maximum deviatoric stress for in situ stress confining condition was equal 95.1 kPa. This result helped in the design of further multistage investigations. The study identified the rheological strain course, which can be broken down into three characterizations: decreasing creep strain rate, transitional constant creep velocity, and accelerating creep deformation. The study found that due to multistage creep loading, the samples were strengthened. Furthermore, there is a visibly “brittle” character of failure, which may be the consequence of the microstructure transformation as a function of time as well as collapse of voids. Due to the glacial tectonic history of the analyzed samples, the reactivation of microcracks might also serve as an explanation. The number of the various sizes of shear planes after failure is confirmed by XμCT overexposure.</p></abstract>

The study concerns soil creep deformation in multistage triaxial stress tests under drained conditions. High resolution X-ray computed microtomography (XμCT) was involved in structure recognition before and after triaxial tests. Undisturbed Neogene clay samples, which are widespread in central Poland, were used in this study. XμCT was used to identify representative sample series and informed the detection and rejection of unreliable ones. Maximum deviatoric stress for in situ stress confining condition was equal 95.1 kPa. This result helped in the design of further multistage investigations. The study identified the rheological strain course, which can be broken down into three characterizations: decreasing creep strain rate, transitional constant creep velocity, and accelerating creep deformation. The study found that due to multistage creep loading, the samples were strengthened. Furthermore, there is a visibly “brittle” character of failure, which may be the consequence of the microstructure transformation as a function of time as well as collapse of voids. Due to the glacial tectonic history of the analyzed samples, the reactivation of microcracks might also serve as an explanation. The number of the various sizes of shear planes after failure is confirmed by XμCT overexposure.

Preliminary Investigations of Creep Strain of Neogene Clay from Warsaw in Drained Triaxial Tests Assisted by Computed Microtomography

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The study concerns soil creep deformation in multistage triaxial stress tests under drained conditions. High resolution X-ray computed microtomography (XμCT)...

Preliminary Investigations of Creep Strain of Neogene Clay from Warsaw in Drained Triaxial Tests Assisted by Computed Microtomography

Published Online: Aug 01, 2017

Page range: 35 - 49

DOI: https://doi.org/10.1515/sgem-2017-0014

Keywords
microstructure, multistage creep tests, strain rate, undisturbed Neogene clay

© by Łukasz Dominik Kaczmarek

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Preliminary Investigations of Creep Strain of Neogene Clay from Warsaw in Drained Triaxial Tests Assisted by Computed Microtomography

Published Online: Aug 01, 2017

Page range: 35 - 49

DOI: https://doi.org/10.1515/sgem-2017-0014

Keywordsmicrostructure, multistage creep tests, strain rate, undisturbed Neogene clay

© by Łukasz Dominik Kaczmarek

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
microstructure, multistage creep tests, strain rate, undisturbed Neogene clay