A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis
In addressing the issue of strength degradation in saline soil foundations under the salt-freeze coupling effects, a binary medium constitutive model suitable for un-solidified and solidified frozen saline soil is proposed considering both bonding and friction effects. To verify the validity of the...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-01-01
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| Series: | Fractal and Fractional |
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| Online Access: | https://www.mdpi.com/2504-3110/8/1/33 |
| _version_ | 1797343961443991552 |
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| author | Xinrui Kang Hongbo Li Gang Zhang Sheng Li Long Shan Jing Zhao Zhe Zhang |
| author_facet | Xinrui Kang Hongbo Li Gang Zhang Sheng Li Long Shan Jing Zhao Zhe Zhang |
| author_sort | Xinrui Kang |
| collection | DOAJ |
| description | In addressing the issue of strength degradation in saline soil foundations under the salt-freeze coupling effects, a binary medium constitutive model suitable for un-solidified and solidified frozen saline soil is proposed considering both bonding and friction effects. To verify the validity of the constitutive model, freezing triaxial tests are carried out under different negative temperatures, confining pressures, and water contents. The pore structure and fractal characteristics of saline soil are analyzed using mercury intrusion porosimetry (MIP) and the fractal dimension <i>D</i> qualitatively and quantitatively, which shed light on the strength enhancement mechanism during the solidification of frozen saline soils. The results show that the constitutive model for frozen solidified saline soil based on binary medium theory aptly captures the stress–strain relationship before and after the solidification of frozen saline soil. The stress–strain relationship of frozen saline soil before and after solidification can be delineated into linear elasticity, elastoplasticity, and strain-hardening or -softening phases. Each of these phases can be coherently interpreted through the binary medium constitutive model. The un-solidified and solidified frozen both show pronounced fractal characteristics in fractal analysis. Notably, the fractal dimension <i>D</i> of the solidified saline soil exhibits a significant increase compared to that of un-solidified ones. In Regions I and III, the values of <i>D</i> for solidified saline soil are lower than those for untreated saline soil, which is attributed to the filling effect of hydration products and un-hydrated solidifying agent particles. In Region II, the fractal dimensions <i>D<sub>M</sub></i><sub>II</sub> and <i>D<sub>N</sub></i><sub>II</sub> of the solidified saline soil exhibit a “non-physical state”, which is mainly caused by the formation of a significant number of inkpot-type pores due to the binding of soil particles by hydration products. |
| first_indexed | 2024-03-08T10:55:23Z |
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| id | doaj.art-83367754141447a9a2e84baf618cd9fd |
| institution | Directory Open Access Journal |
| issn | 2504-3110 |
| language | English |
| last_indexed | 2024-03-08T10:55:23Z |
| publishDate | 2024-01-01 |
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| record_format | Article |
| series | Fractal and Fractional |
| spelling | doaj.art-83367754141447a9a2e84baf618cd9fd2024-01-26T16:35:38ZengMDPI AGFractal and Fractional2504-31102024-01-01813310.3390/fractalfract8010033A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics AnalysisXinrui Kang0Hongbo Li1Gang Zhang2Sheng Li3Long Shan4Jing Zhao5Zhe Zhang6College of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaCollege of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaCollege of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaCollege of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaCollege of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaCollege of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaCollege of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaIn addressing the issue of strength degradation in saline soil foundations under the salt-freeze coupling effects, a binary medium constitutive model suitable for un-solidified and solidified frozen saline soil is proposed considering both bonding and friction effects. To verify the validity of the constitutive model, freezing triaxial tests are carried out under different negative temperatures, confining pressures, and water contents. The pore structure and fractal characteristics of saline soil are analyzed using mercury intrusion porosimetry (MIP) and the fractal dimension <i>D</i> qualitatively and quantitatively, which shed light on the strength enhancement mechanism during the solidification of frozen saline soils. The results show that the constitutive model for frozen solidified saline soil based on binary medium theory aptly captures the stress–strain relationship before and after the solidification of frozen saline soil. The stress–strain relationship of frozen saline soil before and after solidification can be delineated into linear elasticity, elastoplasticity, and strain-hardening or -softening phases. Each of these phases can be coherently interpreted through the binary medium constitutive model. The un-solidified and solidified frozen both show pronounced fractal characteristics in fractal analysis. Notably, the fractal dimension <i>D</i> of the solidified saline soil exhibits a significant increase compared to that of un-solidified ones. In Regions I and III, the values of <i>D</i> for solidified saline soil are lower than those for untreated saline soil, which is attributed to the filling effect of hydration products and un-hydrated solidifying agent particles. In Region II, the fractal dimensions <i>D<sub>M</sub></i><sub>II</sub> and <i>D<sub>N</sub></i><sub>II</sub> of the solidified saline soil exhibit a “non-physical state”, which is mainly caused by the formation of a significant number of inkpot-type pores due to the binding of soil particles by hydration products.https://www.mdpi.com/2504-3110/8/1/33solidified saline soilconstitutive modelbonded elementfrictional elementMIPfractal dimension |
| spellingShingle | Xinrui Kang Hongbo Li Gang Zhang Sheng Li Long Shan Jing Zhao Zhe Zhang A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis Fractal and Fractional solidified saline soil constitutive model bonded element frictional element MIP fractal dimension |
| title | A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis |
| title_full | A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis |
| title_fullStr | A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis |
| title_full_unstemmed | A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis |
| title_short | A Binary Medium Constitutive Model for Frozen Solidified Saline Soil in Cold Regions and Its Fractal Characteristics Analysis |
| title_sort | binary medium constitutive model for frozen solidified saline soil in cold regions and its fractal characteristics analysis |
| topic | solidified saline soil constitutive model bonded element frictional element MIP fractal dimension |
| url | https://www.mdpi.com/2504-3110/8/1/33 |
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