土工基础

›› 2017, Vol. 31 ›› Issue (4): 465-467.

• 工程实录 • 上一篇    下一篇

昆明地区压实红黏土抗剪强度特征研究

孙希望1，徐运龙2，杨果岳2，李良吉2   

  1. (1.中铁二院昆明勘察设计研究院有限公司，昆明 650000；2.湘潭大学土木工程与力学学院，湖南湘潭 411100)
  • 收稿日期:2016-09-18 修回日期:2016-10-10 出版日期:2017-08-20 发布日期:2017-08-22
  • 通讯作者: 徐运龙（1992-），男，硕士研究生，研究方向为岩土体变形。
  • 作者简介:孙希望（1976-），男，高级工程师，研究方向为特殊土的力学特性。 
  • 基金资助:

    国家自然科学基金资助项目(51508489);昆明市科技计划资助项目（201401AG023049）

Shear Strength Characteristics of a Compacted Red Clay in Kunming Area

SUN Xiwang1, XU Yunlong2, YANG Guoyue2, LI Liangji2   

  1. (1.CREEC Kunming Survey and Design Institute Co. Ltd., Kunming 650000;
    2.College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan Hunan 411100)
  • Received:2016-09-18 Revised:2016-10-10 Online:2017-08-20 Published:2017-08-22

摘要： 对昆明地区压实红黏土开展直剪与三轴试验，研究了压实红黏土在不同含水率与压实度状态下的抗剪强度特征。结果表明：压实红黏土的抗剪强度随着含水率的增加而降低，随着压实度的增大而增大；黏聚力跟内摩擦角均随着含水率的增大而减小、随压实度增大而增大；含水率小于最优含水率时，含水率的变化对黏聚力影响较大，当含水率大于最优含水率时对黏聚力影响相对较小；压实红黏土的抗剪强度跟含水率以及压实度成线性关系。两种试验结果得到的抗剪强度参数变化趋势相同，但数值差别较大,直剪试验得到的黏聚力为三轴试验的0.58倍，内摩擦角为三轴试验的1.34倍。

关键词: 压实红黏土, 直剪试验, 抗剪强度, 黏聚力, 内摩擦角, 含水率, 压实度

Abstract: Red clay is widely distributed in Southwest China. It has practical engineering importance to study the stressstrain characteristics of the compacted red clay. Both direct shear tests and triaxial shear tests were performed on a series of the compacted red clay samples with different moisture contents and degrees of compaction. Direct shear test results and triaxial shear test results on soils with the samples having the same degree of compaction were compared. The following conclusion can be summarized: The shear strength parameters increase with the degree of compaction and reduce with the moisture contents. Higher tested cohesion are occurred at higher moisture contents or higher degree of compaction. When the moisture content is lower than the optimum moisture content in the Proctor Test, it has more impact on the cohesion; whereas, when moisture content is higher than the optimum moisture content, it only has minor impact on the cohesion value. The shear strength of the compacted red clay is linearly proportional to the moisture content and the degree of compaction. Both direct shear test and triaxial shear test demonstrate similar trends with moisture content as well as the degree of compaction but the shear strength magnitudes are different. The cohesion value obtained from direction shear test is only 0.58 of the value obtained from triaxial shear test. The internal friction angle obtained from the direct shear test is 1.34 times of the value from the triaxial shear test.

Key words: Compacted Red Clay, Direct Shear Tests, Shear Strength, Cohesion, Internal Friction Angle, Moisture Content, Degree of Compact