Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests
Sand liquefaction triggered by earthquakes is a devastating geological disaster and has emerged as an engaging topic in earthquake engineering. With an enhanced understanding of pure sand liquefaction promoted by laboratory research, there is a growing concern, following filed investigations, over t...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-04-01
|
| Series: | Applied Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2076-3417/13/8/4833 |
| _version_ | 1797606577603084288 |
|---|---|
| author | Jiajing Zhao Zhehao Zhu Jiaquan Liu Huaqiao Zhong |
| author_facet | Jiajing Zhao Zhehao Zhu Jiaquan Liu Huaqiao Zhong |
| author_sort | Jiajing Zhao |
| collection | DOAJ |
| description | Sand liquefaction triggered by earthquakes is a devastating geological disaster and has emerged as an engaging topic in earthquake engineering. With an enhanced understanding of pure sand liquefaction promoted by laboratory research, there is a growing concern, following filed investigations, over the influence of fine particles on the liquefaction potential of sand containing inclusions. Efforts have been devoted to clarifying the significance of certain physical indicators (e.g., plasticity index, particle shape and gradation characteristics), and fruitful conclusions can be found in the published literature. However, the relationship between the content of fine particles and the cyclic degradation in liquefaction process seems still unclear. To fill this knowledge gap, three sets of cyclic triaxial tests were performed on various sand–fines mixtures with the dry tamping method. The experimental results revealed that (i) fine particles provided a negative contribution to the global soil structure; (ii) however, the damping ratio measured from the obtained stress–strain loops manifested its independence from the fines content during cyclic degradation. In this paper, we propose a shearing mechanism on the microscopic scale to explain the above contrasting observations. For a given soil fabric, the fine particles around sand-to-sand contact points probably break strong force chains, intensifying the threat of liquefaction. By contrast, these fines play the same role in favouring relative sliding between sand grains during both the loading and unloading stages. As the maximum stored energy and the energy loss per cycle are amplified with the same scaling factor, the damping ratio, defined as the ratio between them, should display a macroscopic invariance in triaxial tests. |
| first_indexed | 2024-03-11T05:17:09Z |
| format | Article |
| id | doaj.art-aeb4f10bb32440f7bed5134c4b885a47 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-11T05:17:09Z |
| publishDate | 2023-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-aeb4f10bb32440f7bed5134c4b885a472023-11-17T18:09:54ZengMDPI AGApplied Sciences2076-34172023-04-01138483310.3390/app13084833Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction TestsJiajing Zhao0Zhehao Zhu1Jiaquan Liu2Huaqiao Zhong3School of Civil Engineering, Shanghai Normal University, Shanghai 201418, ChinaSchool of Civil Engineering, Shanghai Normal University, Shanghai 201418, ChinaSchool of Civil Engineering, Shanghai Normal University, Shanghai 201418, ChinaSchool of Civil Engineering, Shanghai Normal University, Shanghai 201418, ChinaSand liquefaction triggered by earthquakes is a devastating geological disaster and has emerged as an engaging topic in earthquake engineering. With an enhanced understanding of pure sand liquefaction promoted by laboratory research, there is a growing concern, following filed investigations, over the influence of fine particles on the liquefaction potential of sand containing inclusions. Efforts have been devoted to clarifying the significance of certain physical indicators (e.g., plasticity index, particle shape and gradation characteristics), and fruitful conclusions can be found in the published literature. However, the relationship between the content of fine particles and the cyclic degradation in liquefaction process seems still unclear. To fill this knowledge gap, three sets of cyclic triaxial tests were performed on various sand–fines mixtures with the dry tamping method. The experimental results revealed that (i) fine particles provided a negative contribution to the global soil structure; (ii) however, the damping ratio measured from the obtained stress–strain loops manifested its independence from the fines content during cyclic degradation. In this paper, we propose a shearing mechanism on the microscopic scale to explain the above contrasting observations. For a given soil fabric, the fine particles around sand-to-sand contact points probably break strong force chains, intensifying the threat of liquefaction. By contrast, these fines play the same role in favouring relative sliding between sand grains during both the loading and unloading stages. As the maximum stored energy and the energy loss per cycle are amplified with the same scaling factor, the damping ratio, defined as the ratio between them, should display a macroscopic invariance in triaxial tests.https://www.mdpi.com/2076-3417/13/8/4833sand liquefactioncyclic degradationdamping ratiocyclic triaxial test |
| spellingShingle | Jiajing Zhao Zhehao Zhu Jiaquan Liu Huaqiao Zhong Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests Applied Sciences sand liquefaction cyclic degradation damping ratio cyclic triaxial test |
| title | Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests |
| title_full | Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests |
| title_fullStr | Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests |
| title_full_unstemmed | Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests |
| title_short | Damping Ratio of Sand Containing Fine Particles in Cyclic Triaxial Liquefaction Tests |
| title_sort | damping ratio of sand containing fine particles in cyclic triaxial liquefaction tests |
| topic | sand liquefaction cyclic degradation damping ratio cyclic triaxial test |
| url | https://www.mdpi.com/2076-3417/13/8/4833 |
| work_keys_str_mv | AT jiajingzhao dampingratioofsandcontainingfineparticlesincyclictriaxialliquefactiontests AT zhehaozhu dampingratioofsandcontainingfineparticlesincyclictriaxialliquefactiontests AT jiaquanliu dampingratioofsandcontainingfineparticlesincyclictriaxialliquefactiontests AT huaqiaozhong dampingratioofsandcontainingfineparticlesincyclictriaxialliquefactiontests |