土工基础

›› 2018, Vol. 32 ›› Issue (4): 455-460.

• 工程实录 • 上一篇    

含水量对软土无侧限变形影响的试验研究

刘 羊1，孙 茜1,2，阎长虹1   

  1. (1.南京大学地球科学与工程学院，南京 210046；2.南京理工大学紫金学院,南京 210046)
  • 收稿日期:2017-07-18 修回日期:2017-08-02 出版日期:2018-08-20 发布日期:2018-08-23
  • 通讯作者: 阎长虹(1959-)，男，教授，博导，研究方向为水文地质工程地质。
  • 作者简介:刘 羊(1993-)，男，在读硕士研究生，研究方向为软土的蠕变流变。 通讯作者：阎长虹(1959-)，男，教授，博导，研究方向为水文地质工程地质。
  • 基金资助:

    教育部博士点基金项目(20130091110020);江苏科技厅社会发展支撑项目(BE2015675)

Evaluation of Moisture Content on the Unconfined Compressive Strength of Soft Soils

LIU Yang1, SUN Qian1,2, YAN Changhong1   

  1. (1.School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046;
    2.Nanjing University of science & technology Zijin College, Nanjing 210023)
  • Received:2017-07-18 Revised:2017-08-02 Online:2018-08-20 Published:2018-08-23

摘要： 在基槽开挖、基坑的放坡开挖或隧道掘进过程中，临空面附近的土体将发生应力卸荷，其土体由此产生较大的侧向变形，软土表现尤为明显。为了研究此类无侧限条件下软土的变形问题，采用了由常规固结仪改装而成的无侧限压缩试验仪，对原状软土及重塑土进行无侧限压缩试验。试验结果表明，每级荷载施加后，试样均表现出衰减蠕变的特征；与侧限条件相比，无侧限条件下的压缩应变率大大增加；此外，含水量和轴向应力对软土的变形均有很大的影响。通过试验数据拟合，得出了软土应变随含水量和轴向应力的变化关系。

关键词: 无侧限压缩试验, 软土, 含水量, 轴向变形, 侧向变形

Abstract: The soil near the free face will experience the unloading stress in the excavation or tunneling, for which the soil mass will results in the lateral deformation, especially in soft soils. To study theadverse effect of soil deformation under the unconfined condition,a conventional consolidation test apparatus was modified to conduct the unconfined compression test for soft clays. A series of laboratory tests were conducted to investigate the characteristics of the unconfined compression of undisturbed samples as well as remodeling samples. The result shows that the samplespresentthe characteristics of attenuation creep under each loading stage. The strain rate under the unconfined condition is far greater than it under the unidirectional compression condition. Further, the water content and the axial stress have a great influence on the deformation of soft soil. The relationship between strain and water content and axial stress are obtained by statistically fitting test data.

Key words: Unconfined Compression test, Soft Soil, Moisture Content, Axial deformation, Lateral Deformation