土工基础

土工基础 ›› 2021, Vol. 35 ›› Issue (5): 645-648.

• 测试技术 • 上一篇    

有机质对水泥改良红黏土的力学特性影响及微观机理分析

刘海桃1，徐志豪2，邵朝阳3   

  1. （1.湖北建科科技集团，武汉 430000；2.武汉大学 土木建筑工程学院，武汉 430072；3.南华大学 资源环境与安全工程学院，湖南衡阳 421001)
  • 收稿日期:2021-08-12 修回日期:2021-09-01 出版日期:2021-10-31 发布日期:2021-10-22
  • 通讯作者: 徐志豪（1997-），男，博士研究生，研究方向为岩土工程。〖HT〗〖HJ〗〖FQ)〗
  • 作者简介:刘海桃（1982-），男，高级工程师，研究方向为土木工程。

Effect of Organic Matters on Mechanical Properties of Cement Treated Red Clay and its Micro-mechanism

LIU Haitao1, XU Zhihao2, SHAO Zhaoyang3   

  1. (1.Hubei Jianke Technology Group, Wuhan 430000；
    2.School of Civil Engineering, Wuhan University, Wuhan 430072；
    3.School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001)
  • Received:2021-08-12 Revised:2021-09-01 Online:2021-10-31 Published:2021-10-22

摘要： 红黏土中有机质含量是影响水泥土力学特性的重要因素。通过开展不同有机质含量下水泥改良红黏土的强度试验，探究了水泥红黏土中有机质对其变形及力学特性的影响效应；此外，结合SEM与XRD微观测试试验，探析了水泥改良红黏土中有机质的内在影响机理。结果显示，在一定含量范围内试样的粘聚力随有机质含量的增加有所提升，而试样的无侧限抗压强度与内摩擦角均持续减小直至接近影响临界值；在微观层面上，有机质通过抑制试样中水化产物的生成以及诱导其结构形态的转变，进而影响水泥红黏土的宏观力学特性。

关键词: 红黏土, 水泥土, 有机质, 力学特性, 微观结构

Abstract: The organic content in the red clay is an important factor affecting the engineering performance of cement treated soils. By testing the mechanical strength of the treated red clay with different organic content, the effect of organic matter on the deformation and strength properties of the treated red clay was evaluated. The mechanism of organic matter in the cement-treated red clay was analyzed by the Scanning Electronic Microscope (SEM) and X-Ray Diffraction tests. The results show that, within the organic content studied, the tested sample cohesion increases with the organic content, while the unconfined compressive strength and internal friction angle of the sample continue to decrease until close to the critical value of organic content. At the microscopic level, the organic content affects the mechanical properties of the cement treated red clay by inhibiting the formation of hydration products and inducing the transformation of its structure and morphology.

Key words: red clay, cement treated soil, organic matter, mechanical property, microstructure

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