Baotou city of Inner Mongolia is a typical region with seasonal frozen soil where frost heaving and thawing is the main cause of frozen soil damage. The influence of cyclic freezing and thawing on the shear strength of silty soil was investigated by establishing the quantitative relationship of cohesion and internal friction angle against freeze-thaw cycle parameters. Moisture content, dry density, and number of freeze-thaw cycle were controlled in the test. Results showed that cohesion decreased steadily as cyclic freezing and thawing proceeds regardless of dry density and moisture content of soil specimen; internal friction angle stabilized with the proceeding of cyclic freezing and thawing, fluctuating within a range of 5°; shear strength of silty soil was mostly affected by cohesion. In addition, finite element analysis was carried out with geotechnical software, and the safety factor of slope was calculated by the reduction coefficient method. The research is expected to offer better theoretical basis for researching the seasonal frozen soil in Baotou.
Key words
frozen soil /
slope stability /
cyclic freezing and thawing /
cohesion /
internal friction angle /
shear strength /
reduction coefficient method
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References
[1] 中国科学院兰州冰川冻土沙漠研究所. 冻土[M]. 北京: 科学出版社,1975.
[2] 崔托维奇H A.冻土力学[M].张长庆,朱元林,译.北京:科学出版社,1985.
[3] YONG R N,BOONSINSUK P,YIN C W P Alternation of Soil Behaviour after Cyclic Freezing and Thawing[C]∥Proceedings of the 4th International Symposium on Ground Freezing. Sapporo, August 5-7, 1985: 187-195.
[4] CHUVILIN E, YAZYNIN O M. Frozen Soil Macro-and Microstructure Formation[C]∥Proceedings of the 5th International Conference on Permafrost. Norway, August 2-5, 1988: 320-323.
[5] BRAMS B B, YAO L YC. Shear Strength of a Soil after Freezing and Thawing[J]. ASCE Journal of the Soil Mechanics and Foundations Division,1964,90(4): 1-26.
[6] BONDARENKO G, SADOVSKY V. Water Content Effect of the Thawing Clay Soils on Shear Strength[C]∥Proceedings of the 7th International Symposium on Ground Freezing. Nancy, France, October 24-28, 1994: 123-127.
[7] AOYAMA K, OGAWA S, FUKUDA M. Temperature Dependencies of Mechanical Properties of Soils Subjected to Freezing and Thawing[C]∥Proceedings of the 4th International Symposium on Ground Freezing. Sapporo, August 5-7, 1985: 217-222.
[8] 倪万魁,师华强. 冻融循环作用对黄土微结构和强度的影响[J]. 冰川冻土,2014,36(4):922-927.
[9] 杨成松,何 平,程国栋,等. 冻融作用对土体干容重和含水量影响的试验研究[J].岩石力学与工程学报,2003,22(增2):2695-2699.
[10]董晓宏,张爱军,连江波,等.长期冻融循环引起黄土强度劣化的试验研究[J]. 工程地质学报,2010,18(6):887-893.
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