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膨胀土收缩开裂过程及其温度效应

唐朝生, 崔玉军, Anh-minhTang, 施斌

唐朝生, 崔玉军, Anh-minhTang, 施斌. 膨胀土收缩开裂过程及其温度效应[J]. 岩土工程学报, 2012, 34(12): 2181-2187.
引用本文: 唐朝生, 崔玉军, Anh-minhTang, 施斌. 膨胀土收缩开裂过程及其温度效应[J]. 岩土工程学报, 2012, 34(12): 2181-2187.
TANG Chao-sheng, CUI Yu-jun, Anh-minh Tang, SHI Bin. Shrinkage and desiccation cracking process of expansive soil and its temperature-dependent behaviour[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(12): 2181-2187.
Citation: TANG Chao-sheng, CUI Yu-jun, Anh-minh Tang, SHI Bin. Shrinkage and desiccation cracking process of expansive soil and its temperature-dependent behaviour[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(12): 2181-2187.

膨胀土收缩开裂过程及其温度效应  English Version

详细信息
    作者简介:

    唐朝生(1980- ),男,湖南衡阳人,博士,主要从事环境岩土工程和工程地质方面的教学和研究工作。E-mail: tangchaosheng@nju.edu.cn。

  • 中图分类号: TU43

Shrinkage and desiccation cracking process of expansive soil and its temperature-dependent behaviour

  • 摘要: 温度作为主要的外部环境因素之一,对膨胀土水-力学性质有重要影响。为了了解膨胀土在不同温度条件下的干缩开裂特性,开展了一系列干燥试验。试验中共配制了9组初始饱和的泥浆试样,干燥环境温度分别为22℃,60℃和105℃。在干燥过程中,实时监测试样的含水率变化及表面裂隙的演化过程,利用数字图像处理技术,对裂隙图像进行了定量分析,获得了表面裂隙率Rsc;采用填充法,测量了裂隙的体积。结果表明:在干燥初期,试样中水分蒸发速率为常数,且随温度的增加而增加,试样达到残余含水率所需时间随温度的增加而减小;裂隙出现时对应的临界含水率wIC受温度的影响非常明显,当温度从22℃增加到105℃时,wIC从38.0%增加到90.9%;在裂隙发展前期,Rsc增速较缓,随后进入快速发展期,较小的含水率变化可导致Rsc迅速增加;当含水率接近终期临界含水率wFC或缩限时,裂隙发展趋于稳定,且wFC基本不受温度的影响;在高温环境下,膨胀土的裂隙发育程度较低温环境高,存在明显的温度效应。
    Abstract: During drying, expansive soil shrinks and induces desiccation cracks on surface due to water evaporation. The presence of cracks significantly weakens soil structure and stability, and results in various engineering problems. Better understanding the processes of shrinkage and desiccation cracking is essential in analyzing drought effects on buildings constructed on expansive soil. As temperature is one of the most important external factors that control the hydro-mechanical behaviour, desiccation tests are therefore conducted on initially saturated expansive soil slurry to investigate the temperature effects on shrinkage and cracking characteristics. Nine specimens are prepared and dried under 22°C, 60°C and 105°C respectively. Water loss and surface crack evolution are monitored during the whole drying period. The image processing technique is employed to quantitatively characterize the crack pattern, and surface crack ratio Rsc is determined to describe surface cracking extent. In addition, the filling method is used to measure the crack volume by using pure sands. It is found that the initial evaporation rate of soil water is constant and increases with increasing temperature; the drying period that needs to reach the residual water content decreases with increasing temperature; and the initial critical water content wIC at the onset of cracking is significantly influenced by temperature as temperature increases from 22 to 105 °C, wIC increases from 38.0 to 90.9%. After crack initiation, it is found that the ratio Rsc increases slowly at the beginning stage, and then increases quickly even when water content decreases slightly. However, as the water content reaches the final critical water content wFC or shrinkage limit, Rsc gradually reaches stabilization, and the effect of temperature on wFC is insignificant. The experimental results also show that the desiccation cracking behaviour of expansive soil significantly depends on environmental temperature; in general, the higher the temperature, the more the development of cracks on specimen surface.
  • [1] MORRIS P H, GRAHAM J, WILIAMS D J. Cracking in drying soils[J]. Canadian Geotechnical Journal, 1992,29:263-267
    [2] NELSON J D, MILLER D J. Expansive soils: problems and practice in foundation and pavement engineering[M]. New York: John Wiley, 1992.
    [3] ALBRECHT B A. BENSON C H. Effect of desiccation on compacted natural clays[J]. ASCE J of Geotech and Geoenvir Engrg, 2001,1271:67-75
    [4] MILLER C J, MI H, YESILLER N. Experimental analysis of desiccation crack propagation in clay liners[J]. Journal of the American Water Resources Association, 1998,34(3):677-686
    [5] 姚海林,郑少河,陈守义. 考虑裂隙及雨水入渗影响的膨胀土边坡稳定性分析[J]. 岩土工程学报, 2001,23(5):606-609
    YAO Hai-lin, ZHENG Shao-he, CHEN Shou-yi. Analysis on the slope stability of expansive soils considering cracks and infiltration of rain[J]. Chinese Journal of Geotechnical Engineering, 2001,23(5):606-609. (in Chinese))
    [6] 孔令伟,陈建斌,郭爱国,等. 大气作用下膨胀土边坡的现场响应试验研究[J]. 岩土工程学报, 2007,29(7):1065-1073
    KONG Ling-wei, CHEN Jian-bin, GUO Ai-guo,et al. Field response tests on expansive soil slopes under atmosphere[J]. Chinese Journal of Geotechnical Engineering, 2007,29(7):1065-1073. (in Chinese))
    [7] SILVESTRI V, SARKIS G, BEKKOUCHE N,et al. Evapotranspiration, trees and damage to foundations in sensitive clays[C]// Canadian Geotechnical Conference, 1992, Vol. II: 533-538.
    [8] MILLER C J, MI H, YESILLER N. Experimental analysis of desiccation crack propagation in clay liners[J]. Journal of the American Water Resources Association, 1998,34(3):677-686
    [9] VOGEL H J, HOFMANN H, ROTH K. Studies of crack dynamics in clay soil: experimental methods, results, and morphological quantification[J]. Geoderma, 2005,125:203-211
    [10] 唐朝生,施 斌,刘 春,等. 黏性土在不同温度下干缩裂缝的发展规律及形态学定量分析[J]. 岩土工程学报, 2007,29(5):743-749
    TANG Chao-Sheng, SHI Bin, LIU Chun,et al. Developing law and morphological analysis of shrinkage cracks of clay soil at different temperature[J]. Chinese Journal of Geotechnical Engineering, 2007,29(5):743-749. (in Chinese))
    [11] 唐朝生,施 斌,刘 春,等. 影响黏性土表面干缩裂缝结构形态的因素及定量分析[J]. 水利学报, 2007,38(10):1186-1193
    TANG Chao-sheng, SHI Bin, LIU Chun,et al. Factors affecting of the surface shrinkage cracks’ structure and morphology of clay soil and quantitative analysis[J]. Journal of Hydraulic Engineering, 2007,38(10):1186-1193. (in Chinese))
    [12] 刘 春,王宝军,施 斌,等. 基于数字图像识别的岩土体裂隙形态参数分析方法[J]. 岩土工程学报, 2008,30(9):1383-1388
    LIU Chun, WANG Bao-jun, SHI Bin,et al. The analysis method of Morphological parameters of rock and soil crack based on image processing and recognition[J]. Chinese Journal of Geotechnical Engineering, 2008,30(9):1383-1388. (in Chinese))
    [13] TANG C, SHI B, LIU C,et al. Influencing factors of geometrical structure of surface shrinkage cracks in clayey soils[J]. Engineering Geology, 2008,101(3/4):204-217
    [14] TANG C S, CUI Y J, TANG A M,et al. Experiment evidence on the temperature dependence of desiccation cracking behavior of clayey soils[J]. Engineering Geology, 2010,114:261-266
    [15] KAYYAL M K. Effect of the moisture evaporative stages on the development of shrinkage cracks in soil[C]// Proceedings of First International Conference on Unsaturated Soils, 1995: 373-379.
    [16] PRAT P C, LEDESMA A, LAKSHMIKANTHA M R. Size effect in the cracking of drying soil[C]// Proceedings of the 16th European Conference of Fracture. Springer, 2006.
    [17] RODRÍGUEZ R, SÁNCHEZ M, LEDESMA A,et al. Experimental and numerical analysis of desiccation of a mining waste[J]. Canadian Geotechnical Journal, 2007,44:644-658
    [18] HILLEL D. Introduction to soil physical[M]. New York: Academic Press, 1982.
    [19] TANG A M, CUI Y J. Controlling suction by the vapour equilibrium technique at different temperatures and its application in determining the water retention properties of MX80 clay[J]. Canadian Geotechnical Journal, 2005,42:1-10
    [20] VILLAR M V, LLORE A. Influence of temperature on the hydro-mechanical behaviour of a compacted bentonite[J]. Applied Clay Science, 2004,26:337-350
    [21] CORTE A, HIGASHI A. Experimental research on desiccation cracks in soil[R]. Research report 66, U.S. Army Snow Ice and Permafrost Research Estabilishment,Wilmette, Illinois, 1960
    [22] MITCHELL J K. Shearing resistance of soils as a rate process[J]. ASCE Journal of Soil Mechanics and Foundation, Engineering Division, 1964, 90(1): 231–251.
    [23] HUECKEL T, BALDI G. Thermoplasticity of saturated clays: Experimental constitute study[J]. ASCE Journal of Geotechnical Engineering, 1990, 116(12): 1178–1769.
    [24] BRONSWIJK J J B. Modeling of water balance, cracking and subsidence of clay soils[J]. J Hydrol (Amsterdam), 1988, 97: 199–212.
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出版历程
  • 收稿日期:  2010-12-17
  • 发布日期:  2012-12-24

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