Sciences in Cold and Arid Regions ›› 2017, Vol. 9 ›› Issue (4): 404–411.doi: 10.3724/SP.J.1226.2017.00404

• ARTICLES • 上一篇    

Strength of undisturbed and reconstituted frozen soil at temperatures close to 0℃

XiaoDong Zhao1, GuoQing Zhou1, GuiLin Lu2, Yue Wu1, Wei Jiao1, Jing Yu1   

  1. 1. State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China;
    2. Xuzhou Urban Rail Transit Co. Ltd., Xuzhou, Jiangsu 221000, China
  • 收稿日期:2017-02-25 修回日期:2017-03-25 发布日期:2018-11-23
  • 通讯作者: XiaoDong Zhao, State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology. No. 1, Daxue Road, Xuzhou, Jiangsu 221116, China. Tel: +86-516-83995678; E-mail: zxd@cumt.edu.cn E-mail:zxd@cumt.edu.cn
  • 基金资助:
    This research was supported by National Natural Science Foundation of China (No. 51304209), the Natural Science Foundation of Jiangsu Province of China (No. BK20141135), and the Fundamental Research Funds for the Central Universities (No. 2015QNA63).

Strength of undisturbed and reconstituted frozen soil at temperatures close to 0℃

XiaoDong Zhao1, GuoQing Zhou1, GuiLin Lu2, Yue Wu1, Wei Jiao1, Jing Yu1   

  1. 1. State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China;
    2. Xuzhou Urban Rail Transit Co. Ltd., Xuzhou, Jiangsu 221000, China
  • Received:2017-02-25 Revised:2017-03-25 Published:2018-11-23
  • Contact: XiaoDong Zhao, State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology. No. 1, Daxue Road, Xuzhou, Jiangsu 221116, China. Tel: +86-516-83995678; E-mail: zxd@cumt.edu.cn E-mail:zxd@cumt.edu.cn
  • Supported by:
    This research was supported by National Natural Science Foundation of China (No. 51304209), the Natural Science Foundation of Jiangsu Province of China (No. BK20141135), and the Fundamental Research Funds for the Central Universities (No. 2015QNA63).

摘要: The strength of warm frozen soils in permafrost is fundamentally significant to estimate and predict the ground settlements from construction activities. A study was therefore initiated to assess the strength and its behaviors of undisturbed and reconstituted frozen soils at temperatures close to 0 ℃. A series of triaxial compression tests (TCT) were performed by using a developed testing apparatus and a matching specimen-preparation method. The confinement was applied from air pressure, the temperature in the specimen was maintained using two-end refrigeration, and multi-stage loading on a single specimen was adopted to determine the strength. The test results showed that the strength, both for the undisturbed and reconstituted frozen-soil specimens, was significantly dependent on the temperatures and independent of the applied confining pressures. Additionally, the strength of undisturbed frozen soils was about 1.6 times more than that for reconstituted frozen soils. These observations were closely associated with the structures existing between pore-ice and gravels with large diameters.

关键词: warm frozen soils, strength behaviors, undisturbed specimen

Abstract: The strength of warm frozen soils in permafrost is fundamentally significant to estimate and predict the ground settlements from construction activities. A study was therefore initiated to assess the strength and its behaviors of undisturbed and reconstituted frozen soils at temperatures close to 0 ℃. A series of triaxial compression tests (TCT) were performed by using a developed testing apparatus and a matching specimen-preparation method. The confinement was applied from air pressure, the temperature in the specimen was maintained using two-end refrigeration, and multi-stage loading on a single specimen was adopted to determine the strength. The test results showed that the strength, both for the undisturbed and reconstituted frozen-soil specimens, was significantly dependent on the temperatures and independent of the applied confining pressures. Additionally, the strength of undisturbed frozen soils was about 1.6 times more than that for reconstituted frozen soils. These observations were closely associated with the structures existing between pore-ice and gravels with large diameters.

Key words: warm frozen soils, strength behaviors, undisturbed specimen

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