Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway
Sichuan—Tibet railway is in the topographic crossing zone from the Sichuan basin to Qinghai Tibet Plateau. Regional characteristic geological factors such as active structure, valley unloading and freeze-thaw weathering along the line have strong control over the development and stability of unstabl...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Editorial Department of Journal of Sichuan University (Engineering Science Edition)
2022-03-01
|
| Series: | 工程科学与技术 |
| Subjects: | |
| Online Access: | http://jsuese.scu.edu.cn/thesisDetails#10.15961/j.jsuese.202100561 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850031836510552064 |
|---|---|
| author | Guangze ZHANG Guoqing CHEN Zhewei WANG Dong WANG Bencan PEI |
| author_facet | Guangze ZHANG Guoqing CHEN Zhewei WANG Dong WANG Bencan PEI |
| author_sort | Guangze ZHANG |
| collection | DOAJ |
| description | Sichuan—Tibet railway is in the topographic crossing zone from the Sichuan basin to Qinghai Tibet Plateau. Regional characteristic geological factors such as active structure, valley unloading and freeze-thaw weathering along the line have strong control over the development and stability of unstable rocks. It is of great significance for railway route selection in the early stage to carry out the investigation of unstable rocks and the research on the rapid evaluation method of stability. Based on the interpretation of remote sensing and unmanned aerial vehicle images with verification of field investigation, the development characteristics of unstable rock at the entrance and exit of tunnels along the Sichuan—Tibet railway from Ya’an to Changdu were summarized, and the failure mode and rapid evaluation method of stability at high altitude were put forward considering the regional geological characteristics. The results show that: 1) There were 141 unstable rocks developed in the small and medium size (<1 000 m<sup>3</sup>). The deep canyon areas such as Dadu River, Yalong River and Jinsha River were the most densely developed. 2) The unstable rock was mainly developed in the freeze-thaw weathered Triassic sand-slate interbedded phyllite section above 3 000 m, accompanying with low stability; 3) The distribution of unstable rock was also related to the high seismic intensity area and active fault. The failure mode of unstable rock in this region showed that multiple indexes were coupled with each other, including the unloading behavior of ground stress, persist damage of freeze-thaw, and intermittent seismicity. Eight indexes were extracted, including special geological indexes of the Sichuan—Tibet area, the freeze-thaw, unloading behavior and seismic intensity, and five basic indexes of stability evaluation of unstable rock, terrain gradient, weathering intensity of rock mass, cavity, main control structural plane and lithology. The stability evaluation model of unstable rock in the cold region was established based on extension theory through comprehensively estimating the weight and relevancy of each index for the four stability levels. Analysis results of seven cases suggested that the stability estimation and controlling indexes were in accord with the field situation by using this method, which could quickly identify the stability of unstable rock in the alpine mountainous area of the Sichuan—Tibet railway. |
| format | Article |
| id | doaj-art-7ac9a49759a3429da75fbdf61998b95a |
| institution | DOAJ |
| issn | 2096-3246 |
| language | English |
| publishDate | 2022-03-01 |
| publisher | Editorial Department of Journal of Sichuan University (Engineering Science Edition) |
| record_format | Article |
| series | 工程科学与技术 |
| spelling | doaj-art-7ac9a49759a3429da75fbdf61998b95a2025-08-20T02:58:51ZengEditorial Department of Journal of Sichuan University (Engineering Science Edition)工程科学与技术2096-32462022-03-0154304047403721Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet RailwayGuangze ZHANGGuoqing CHENZhewei WANGDong WANGBencan PEISichuan—Tibet railway is in the topographic crossing zone from the Sichuan basin to Qinghai Tibet Plateau. Regional characteristic geological factors such as active structure, valley unloading and freeze-thaw weathering along the line have strong control over the development and stability of unstable rocks. It is of great significance for railway route selection in the early stage to carry out the investigation of unstable rocks and the research on the rapid evaluation method of stability. Based on the interpretation of remote sensing and unmanned aerial vehicle images with verification of field investigation, the development characteristics of unstable rock at the entrance and exit of tunnels along the Sichuan—Tibet railway from Ya’an to Changdu were summarized, and the failure mode and rapid evaluation method of stability at high altitude were put forward considering the regional geological characteristics. The results show that: 1) There were 141 unstable rocks developed in the small and medium size (<1 000 m<sup>3</sup>). The deep canyon areas such as Dadu River, Yalong River and Jinsha River were the most densely developed. 2) The unstable rock was mainly developed in the freeze-thaw weathered Triassic sand-slate interbedded phyllite section above 3 000 m, accompanying with low stability; 3) The distribution of unstable rock was also related to the high seismic intensity area and active fault. The failure mode of unstable rock in this region showed that multiple indexes were coupled with each other, including the unloading behavior of ground stress, persist damage of freeze-thaw, and intermittent seismicity. Eight indexes were extracted, including special geological indexes of the Sichuan—Tibet area, the freeze-thaw, unloading behavior and seismic intensity, and five basic indexes of stability evaluation of unstable rock, terrain gradient, weathering intensity of rock mass, cavity, main control structural plane and lithology. The stability evaluation model of unstable rock in the cold region was established based on extension theory through comprehensively estimating the weight and relevancy of each index for the four stability levels. Analysis results of seven cases suggested that the stability estimation and controlling indexes were in accord with the field situation by using this method, which could quickly identify the stability of unstable rock in the alpine mountainous area of the Sichuan—Tibet railway.http://jsuese.scu.edu.cn/thesisDetails#10.15961/j.jsuese.202100561Sichuan—Tibet railwaydevelopment characteristics of unstable rocktunnel portaldisaster moderapid evaluation methodextenics theory |
| spellingShingle | Guangze ZHANG Guoqing CHEN Zhewei WANG Dong WANG Bencan PEI Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway 工程科学与技术 Sichuan—Tibet railway development characteristics of unstable rock tunnel portal disaster mode rapid evaluation method extenics theory |
| title | Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway |
| title_full | Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway |
| title_fullStr | Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway |
| title_full_unstemmed | Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway |
| title_short | Development Characteristics and Rapid Evaluation of High-steep Unstable Rock in Ya’an—Changdu Section of Sichuan—Tibet Railway |
| title_sort | development characteristics and rapid evaluation of high steep unstable rock in ya an changdu section of sichuan tibet railway |
| topic | Sichuan—Tibet railway development characteristics of unstable rock tunnel portal disaster mode rapid evaluation method extenics theory |
| url | http://jsuese.scu.edu.cn/thesisDetails#10.15961/j.jsuese.202100561 |
| work_keys_str_mv | AT guangzezhang developmentcharacteristicsandrapidevaluationofhighsteepunstablerockinyaanchangdusectionofsichuantibetrailway AT guoqingchen developmentcharacteristicsandrapidevaluationofhighsteepunstablerockinyaanchangdusectionofsichuantibetrailway AT zheweiwang developmentcharacteristicsandrapidevaluationofhighsteepunstablerockinyaanchangdusectionofsichuantibetrailway AT dongwang developmentcharacteristicsandrapidevaluationofhighsteepunstablerockinyaanchangdusectionofsichuantibetrailway AT bencanpei developmentcharacteristicsandrapidevaluationofhighsteepunstablerockinyaanchangdusectionofsichuantibetrailway |