Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure
Different from the other roadbed material, the unique mechanical properties of aeolian sand bring great difficulties to the construction and maintenance of desert highways. However, the main attention was usually paid to the engineering properties of aeolian sand, such as collapsibility, strong perm...
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MDPI AG
2022-03-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/12/6/3020 |
| _version_ | 1797472954249904128 |
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| author | Xuefeng Li Wendong Xu Lei Chang Wenwei Yang |
| author_facet | Xuefeng Li Wendong Xu Lei Chang Wenwei Yang |
| author_sort | Xuefeng Li |
| collection | DOAJ |
| description | Different from the other roadbed material, the unique mechanical properties of aeolian sand bring great difficulties to the construction and maintenance of desert highways. However, the main attention was usually paid to the engineering properties of aeolian sand, such as collapsibility, strong permeability, and poor gradation. To investigate the shear behaviour of aeolian sand under different engineering conditions, the drained and undrained tests were performed on aeolian sand with relatively large range of density and confining pressure. Under this condition, both the drained and undrained tests tend to the same critical state line, and the shear behaviour of aeolian sand is directly dependent on its density. Under the undrained condition, the <i>q</i>-<i>ε</i><sub>1</sub> curves and the effective stress paths in triaxial stress space exhibit four types of undrained shear behaviour, such as flow, limited flow, strain hardening, and strain softening. Meanwhile all the specimens exhibit three types of failure, such as flow slip, bulging failure, and shear bands. In the <i>q</i>-<i>p</i>’ plane, the analogous drained and undrained stress paths can be followed by aeolian sand with same initial relative density but different confining pressures, and there are two critical state lines due to the generation of shear bands for dense sand. In addition, the critical state lines in <i>e</i>-ln<i>p</i>’ plane decrease with increasing initial relative density <i>D</i><sub>r</sub>, that is, the material constant <i>e</i><sub>ᴦ</sub> decreases with increasing <i>D</i><sub>r</sub>, and the <i>λ</i> is also not constant but decreases with the increase in <i>D</i><sub>r</sub>. The results suggest that the strength behaviours of aeolian sand can be fitted by a straight line considering relative density and confining pressure and that two empirical formulas are established to describe this feature. |
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| language | English |
| last_indexed | 2024-03-09T20:08:23Z |
| publishDate | 2022-03-01 |
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| series | Applied Sciences |
| spelling | doaj.art-12a21b8aebcf435bb4f118c856aee82a2023-11-24T00:22:30ZengMDPI AGApplied Sciences2076-34172022-03-01126302010.3390/app12063020Shear Behaviour of Aeolian Sand with Different Density and Confining PressureXuefeng Li0Wendong Xu1Lei Chang2Wenwei Yang3School of Physics and Electronic-Electrical Engineering, Ningxia University, Yinchuan 750021, ChinaSolid Mechanics Institute, Ningxia University, Yinchuan 750021, ChinaShenzhen Houkun Soft Rock Technology Co., Ltd., Shenzhen 518031, ChinaSchool of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, ChinaDifferent from the other roadbed material, the unique mechanical properties of aeolian sand bring great difficulties to the construction and maintenance of desert highways. However, the main attention was usually paid to the engineering properties of aeolian sand, such as collapsibility, strong permeability, and poor gradation. To investigate the shear behaviour of aeolian sand under different engineering conditions, the drained and undrained tests were performed on aeolian sand with relatively large range of density and confining pressure. Under this condition, both the drained and undrained tests tend to the same critical state line, and the shear behaviour of aeolian sand is directly dependent on its density. Under the undrained condition, the <i>q</i>-<i>ε</i><sub>1</sub> curves and the effective stress paths in triaxial stress space exhibit four types of undrained shear behaviour, such as flow, limited flow, strain hardening, and strain softening. Meanwhile all the specimens exhibit three types of failure, such as flow slip, bulging failure, and shear bands. In the <i>q</i>-<i>p</i>’ plane, the analogous drained and undrained stress paths can be followed by aeolian sand with same initial relative density but different confining pressures, and there are two critical state lines due to the generation of shear bands for dense sand. In addition, the critical state lines in <i>e</i>-ln<i>p</i>’ plane decrease with increasing initial relative density <i>D</i><sub>r</sub>, that is, the material constant <i>e</i><sub>ᴦ</sub> decreases with increasing <i>D</i><sub>r</sub>, and the <i>λ</i> is also not constant but decreases with the increase in <i>D</i><sub>r</sub>. The results suggest that the strength behaviours of aeolian sand can be fitted by a straight line considering relative density and confining pressure and that two empirical formulas are established to describe this feature.https://www.mdpi.com/2076-3417/12/6/3020densityconfining pressureaeolian sandtriaxial teststress-straincritical state |
| spellingShingle | Xuefeng Li Wendong Xu Lei Chang Wenwei Yang Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure Applied Sciences density confining pressure aeolian sand triaxial test stress-strain critical state |
| title | Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure |
| title_full | Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure |
| title_fullStr | Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure |
| title_full_unstemmed | Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure |
| title_short | Shear Behaviour of Aeolian Sand with Different Density and Confining Pressure |
| title_sort | shear behaviour of aeolian sand with different density and confining pressure |
| topic | density confining pressure aeolian sand triaxial test stress-strain critical state |
| url | https://www.mdpi.com/2076-3417/12/6/3020 |
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