Effects of moisture and density states on unsaturated shear strength of compacted expansive soil

被引：0
|
作者：
Zhou B.-C. [1 ]
Kong L.-W. [2 ]
Ma Q.-G. [1 ]
Luo Z.-T. [1 ]
Zhang Y.-J. [1 ]
机构：
[1] College of Architecture and Civil Engineering, Xinyang Normal University, Xinyang, 464000, Henan
[2] State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, Hubei
来源：
Yantu Lixue/Rock and Soil Mechanics | 2017年 / 38卷
关键词：
Compacted soils; Density effect; Peak effect; Shear strength; Stress plummeting; Unsaturated soils;
D O I：
10.16285/j.rsm.2017.S1.029
中图分类号：
学科分类号：
摘要：
To investigate unsaturated shear strength of compacted expansive soil within the entire range of moisture and density state, the unsaturated direct shear tests are conducted on Jingmen expansive soil associated with 38 types of moisture and density state combinations. The distribution of shear strength are obtained with respect to moisture state varying from air-dry to saturation and density represented by void ratio ranging from 0.539 to 1.089. Conclusions are as follows: (1) Strain-softening phenomenon is observed in shear for most samples. In contrast, strain-hardening phenomenon is observed in shear only for the lower-density and higher-moisture state combination. Stress plummeting phenomenon is observed in shear for the higher-density and lower-moisture state combination. Plastic deformation capacity of the soil samples is improved by increasing moisture under the same density or improved by decreasing density under the same moisture. (2) With the moisture increasing from air-dry to saturation, the unsaturated shear strength and total cohesion increase and then decrease, which can be called the peak effect. (3) Unsaturated shear strength, total cohesion, and total friction angle all decrease with decreasing density, which can be called the density effect. © 2017, Science Press. All right reserved.
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页码：240 / 246
页数：6
相关论文
共 14 条
  • [1] Chen Z.-H., Wang Y.-S., Xie D.-Y., Effective stress in unsaturated soil, Chinese Journal of Geotechnical Engineering, 16, 3, pp. 62-69, (1994)
  • [2] Tang L.-S., New suggestion on shear strength in unsaturated soil based on suction between grains, Chinese Journal of Geotechnical Engineering, 23, 4, pp. 412-417, (2001)
  • [3] Lu N., Likos W.J., Suction stress characteristic curve for unsaturated soil, Journal of Geotechnical and Geoenvironmental Engineering, 132, 2, pp. 131-142, (2006)
  • [4] Sheng D.-C., Yang C., Discussion of fundamental principles in unsaturated soil mechanics, Chinese Journal of Geotechnical Engineering, 34, 3, pp. 438-456, (2012)
  • [5] Chen Z.-H., On basic theories of unsaturated soils and special soils, Chinese Journal of Geotechnical Engineering, 36, 2, pp. 201-272, (2014)
  • [6] Xie D.-Y., Soil Mechanics for Unsaturated Soils, (2015)
  • [7] Ling H., Yin Z.-Z., Variation of unsaturated soil strength with water contents, Chinese Journal of Rock Mechanics and Engineering, 26, 7, pp. 1499-1503, (2007)
  • [8] Lin H.-Z., Li G.-X., Yu Y.-Z., Et al., Influence of matric suction on shear strength behavior of unsaturated soils, Rock and Soil Mechanics, 28, 9, pp. 1931-1936, (2007)
  • [9] Kong L.-W., Zhou B.-C., Bai H., Et al., Experimental study of deformation and strength characteristics of Jingmen unsaturated expansive soil, Rock and Soil Mechanics, 31, 10, pp. 3036-3042, (2010)
  • [10] Schnellmann R., Rahardjo H., Schneider H.R., Unsaturated shear strength of a silty sand, Engineering Geology, 162, pp. 88-96, (2013)
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