Evolution of fissures and bivariate-bimodal soil-water characteristic curves of expansive soil under drying-wetting cycles

被引：0
|
作者：
Wang S.-J. [1 ,2 ]
Wang X.-Q. [1 ]
Li D. [1 ]
Li X. [1 ]
Liang G.-C. [1 ]
Muhammad Q.H. [1 ]
机构：
[1] College of Engineering and Technology, Southwest University, Chongqing
[2] Chongqing Engineering Research Center for Structure Full-Life-Cycle Health Detection and Disaster Prevention, Chongqing
来源：
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | 2021年 / 43卷
关键词：
Bivariate-bimodal soil-water characteristic curve model; Drying-wetting cycle; Expansive soil; Fracture; Quantitative analysis;
D O I：
10.11779/CJGE2021S1011
中图分类号：
学科分类号：
摘要：
Periodical evaporation and rainfall cause the development of fractured soil, and the fracture has a strong influence on the hydraulic and strength characteristics of the soil. To study the crack development law and soil-water characteristics of expansive soil under the action of drying-wetting cycles, the CT scanning technique and image processing program are used to analyze the evolution process of fissures. The pressure plate instrument is used to test the soil-water characteristic curves of Hefei expansive soil and to study the effect of drying-wetting cycles. The results show that the CT scan combining with the image processing program can obtain the two-dimensional and three-dimensional structures of the internal crack of the sample and its quantitative analysis index, and the fracture development process of each fracture index can be described by the growth curve of the logistic function. The crack has a strong influence on the soil-water characteristic curve of expansive soil, and the one with cracks is in the form of "double peaks." With the increase of the number of drying-wetting cycles, the water-holding capacity of expansive soil is reduced, and the difference of soil-water characteristic curves of samples with different cycles is evident. At the high-suction stage, the soil-water characteristic curves of the expansive soil with different cycles gradually become consistent. The influence of drying-wetting cycles on the SWCC1 and SWCC2 feature points (intake value, residual value) is different. It is found that the average fracture width, internal surface area, average fracture length, fissure development degree of volume and fissure development degree of area are significantly correlated with the water-holding capacity of the expansive soil with cracks. The bivariate-bimodal soil-water characteristic curves are established with the number of drying-wetting cycles and the matrix suction as variables. The test data of soil-water characteristic curves of Hefei expansive soil is used to verify the accuracy and reliability of the model. The saturated water content and fitting parameters are well correlated with the number of drying-wetting cycles. © 2021, Editorial Office of Chinese Journal of Geotechnical Engineering. All right reserved.
引用
收藏
页码：58 / 63
页数：5
相关论文
共 8 条
  • [1] LU Zai-hua, CHEN Zheng-han, PU Yi-bin, A CT study on the crack evolution of expansive soil during drying and wetting cycles, Rock and Soil Mechanics, 23, 4, pp. 417-422, (2002)
  • [2] SUN De-an, HUANG Ding-jun, Soil-water and deformation characteristics of Nanyang expansive soil after wetting-drying cycles, Rock and Soil Mechanics, 36, S1, pp. 115-119, (2015)
  • [3] LI Jin-hui, GUO Ling-bo, ZHANG Li-min, Prediction of SWCC for unsaturated cracked soil considering development process of cracks, Chinese Journal of Rock Mechanics and Engineering, 32, 6, pp. 1288-1296, (2013)
  • [4] ZHANG Jun-ran, XU Qiang, SUN De-an, Simulation of soil-water characteristic curves during drying and wetting cycles, Rock and Soil Mechanics, 35, 3, pp. 689-695, (2014)
  • [5] CHEN Liu-feng, PENG Hua, Experimental study on the water retention properties of the hard clay under cyclic suction conditions, Chinese Journal of Rock Mechanics and Engineering, 35, 11, pp. 2337-2344, (2016)
  • [6] WEI Bing-xu, HUANG Zhen, GAO Bing, Research on the relationship between fracture development rules and strength of the compacted expansive soil, Hydrogeology & Engineering Geology, 42, 1, pp. 100-105, (2015)
  • [7] CHENG Ming-shu, LI Xian, WANG Shi-ji, Et al., Verification of generalized soil-water characteristic curve model considering two stress state variables for unsaturated soils[J], Transactions of the Chinese Society of Agricultural Engineering, 33, 6, pp. 8-17, (2017)
  • [8] BURGER C A, SHACKELFORD C D., Evaluating dual porosity of pelletized diatomaceous earth using bimodal soil-water characteristic curve functions, Canadian Geotechnical Journal, 38, 1, pp. 53-66, (2001)
1