Journal of Shanghai University >
Shear strength of unsaturated Nanyang expansive soil and its prediction
Received date: 2015-02-03
Online published: 2017-02-28
Expansive soil is a problematic soil with swelling and shrinkage. Compared with ordinary clay, the strength is clearly affected by water content. To investigate the effect of water content on the strength of expansive soil, a series of direct shear tests on Nanyang expansive soil with different water contents were carried out. Relationship between shear strength and water content at the same dry density was obtained. Test results show that the shear strength and cohesion decrease with increasing water content, and the internal friction angle changes little. In addition, by introducing macro saturation into the Bishop’s equation for unsaturated soil, the results show that the modified strength equation can well predict strength of unsaturated expansive soil.
Key words： unsaturated soil; shear strength; expansive soil
SUN Hongyun, SUN Dean . Shear strength of unsaturated Nanyang expansive soil and its prediction[J]. Journal of Shanghai University, 2017 , 23(1) : 121 -127 . DOI: 10.3969/j.issn.1007-2861.2015.01.018
[1] 刘特洪. 工程建设中的膨胀土问题[M]. 北京: 中国建筑工业出版社, 1997: 173-174.
[2] 杨庆, 张慧珍, 栾茂田. 非饱和膨胀土抗剪强度的试验研究[J]. 岩石力学与工程学报, 2004, 23(3): 420-425.
[3] 詹良通, 吴宏伟. 吸力对非饱和膨胀土抗剪强度及剪胀特性的影响[J]. 岩土工程学报, 2007, 29(1): 82-87.
[4] 刘斯宏, 汪易森, 朱克生, 等. 有荷条件下南阳膨胀土强度试验及其应用[J]. 水利学报, 2010, 41(3): 361-367.
[5] 张添锋, 孙德安, 刘文捷. 桂林压实红粘土抗剪强度与含水率关系[J]. 上海大学学报(自然科学版), 2014, 20(5): 586-595.
[6] Al-Mhaidib A I, Al-Shamrani M A. Influence of swell on shear strength of expansive soils [C]// Geo Shanghai International Conference. 2006: 160-165.
[7] Fredlund D G, Xing A Q, Fredlund M D, et al. The relationship of the unsaturated soil shear strength to the soil-water characteristic curve [J]. Canadian Geotechnical Journal, 1996, 33(3): 440-448.
[8] 中华人民共和国城乡建设环境保护部. GB J112—87 膨胀土地区建筑技术规范[S]. 北京: 中国计划出版社, 1988.
[9] 中华人民共和国水利部. GB/T 50123—1999 土工试验方法标准[S]. 北京: 中国计划出版社, 2010.
[10] 孙德安, 张俊然, 吕海波. 全吸力范围南阳膨胀土的土水特征曲线[J]. 岩土力学, 2013, 34(7): 1839-1846.
[11] Wheeler S J, Sharma R S, Buisson M S R. Coupling of hydraulic hysteresis and stress-strain behavior in unsaturated soils [J]. Geotechnique, 2003, 53(1): 41-54.
/
| 〈 |
|
〉 |
