• 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引(EI)收录期刊
  • Scopus数据库收录期刊
潘斌, 曾召田, 莫红艳, 刘兆强, 崔哲旗. 胀缩性土收缩特性的温度效应试验[J]. 岩土工程学报, 2022, 44(S1): 115-120. DOI: 10.11779/CJGE2022S1021
引用本文: 潘斌, 曾召田, 莫红艳, 刘兆强, 崔哲旗. 胀缩性土收缩特性的温度效应试验[J]. 岩土工程学报, 2022, 44(S1): 115-120. DOI: 10.11779/CJGE2022S1021
PAN Bin, ZENG Zhao-tian, MO Hong-yan, LIU Zhao-qiang, CUI Zhe-qi. Temperature effects on shrinkage properties of swell-shrink soils[J]. Chinese Journal of Geotechnical Engineering, 2022, 44(S1): 115-120. DOI: 10.11779/CJGE2022S1021
Citation: PAN Bin, ZENG Zhao-tian, MO Hong-yan, LIU Zhao-qiang, CUI Zhe-qi. Temperature effects on shrinkage properties of swell-shrink soils[J]. Chinese Journal of Geotechnical Engineering, 2022, 44(S1): 115-120. DOI: 10.11779/CJGE2022S1021

胀缩性土收缩特性的温度效应试验

Temperature effects on shrinkage properties of swell-shrink soils

  • 摘要: 胀缩性土中因含有较多亲水性黏土矿物,失水收缩开裂现象明显,对土体工程性质有显著影响。以广西地区两种典型的胀缩性土(桂林红黏土和南宁膨胀土)为研究对象,在5~45℃温度下开展了土体收缩试验,对比分析了温度对两种胀缩性土收缩特性的影响规律,阐释了胀缩性土收缩特性温度效应的作用机理。结果表明:①两种胀缩性土的收缩特性受温度影响显著,试样收缩变形随温度的升高均先增大后减小,存在“临界温度Tc=35℃”。②膨胀土比红黏土的收缩变形更大,温度效应更显著。③温度对土体胀缩特性的影响,其本质是土体微观结构的改变和土中水形态的变迁:升温促进了土体骨架由松散向紧密状态转变,宏观表现为收缩变形增大;而达到一定温度后高温引起土颗粒和孔隙水热膨胀、土-水作用加剧,使得土体骨架没有充足的时间向紧密状态转化,这是造成收缩变形减小的主要原因。

     

    Abstract: The swell-shrink soils are prone to water loss, shrinkage and cracking because they contain more hydrophilic clay minerals, which have a significant impact on the engineering properties of soils. Taking two typical expandable soils (Guilin red clay and Nanning expansive soil) in Guangxi as the research object, the soil shrinkage tests are carried out at the temperature of 5℃~45℃. The effects of temperature on the shrinkage characteristics of the two types of expandable soils are compared and analyzed, and the mechanism of temperature effects on the shrinkage characteristics of the expandable soils is explained. The results show that: (1) The shrinkage characteristics of the two kinds of swelling and shrinking soils are significantly affected by the temperature. The shrinkage deformation of the samples increases first and then decreases with the increase of the temperature. There is a critical temperature 35℃. (2) The shrinkage deformation of the expansive soil is larger than that of the red clay, and the temperature effects are more significant. (3) The essence of the effects of temperature on the soil expansion and shrinkage are the change of soil microstructure and the change of water form in the soil. After reaching a certain temperature, the thermal expansion of soil particles and pore water caused by high temperature and the intensification of soil-water interaction make the soil skeleton have no sufficient time to transform into a compact state, which is the main reason for the decrease of shrinkage deformation.

     

/

返回文章
返回