降雨–蒸发条件下膨胀土裂隙演化特征试验研究

doi:10.13722/j.cnki.jrme.2015.0028

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摘要为了解裂隙演化规律，在实验室模拟降雨–蒸发条件，开展一系列干湿循环作用下的膨胀土裂隙演化试验，记录土样干缩开裂、湿化愈合的动态演化过程。利用裂隙图像识别程序对裂隙面积率等参数进行定量分析；采用灌蜡法，观察裂隙最终形态并测量了裂隙的体积。试验结果表明：脱湿过程中裂隙发育分为缓慢→快速→缓滞增长3个阶段，其中，快速增长II阶段可完成整个裂隙发育的80%～90%；当土样基质吸力接近进气值时，土体开始出现裂隙，当含水率w接近缩限值时，裂隙发育接近停滞；干湿循环过程中，新生裂隙并不一定会在原裂隙处产生；干湿循环效应表现为：裂隙在干湿循环的作用下会逐步发育，主要体现在裂隙面积率与裂隙条数的增加，但随着裂隙发育的反复开裂、愈合使得膨胀土体结构趋于松散，拉应力势能储备逐渐降低，后期的干湿循环过程中，裂隙率、裂隙分维等形态参数会趋于稳定。灌蜡法测得裂隙体积167.8 cm3，约占试样总体积的4.8%，这一方法具有设备简单、操作性强的优势，为测量裂隙体积、观测裂隙三维形态提供了新的思路。

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关键词 ：土力学, 脱湿过程, 降雨, 蒸发, 膨胀土, 裂隙, 图像识别

Abstract：To better understand the cracking process of expansive soil，rainfall-evaporation tests in laboratory were conducted to expansive soil. The specimen was weighed and photographed regularly during the test process in order to record the development of cracks. The image processing technique was employed to quantitatively extract the parameters of crack features，such as the crack ratio. In addition，the method of wax filling was used to observe the ultimate shape and measure the volume of cracks. It was found that the cracking process consisted of phases of slow→rapid→slow growth. 80%–90% of cracks appeared in the 2nd phase. The cracks appeared when the matric suction approached to the air-entry pressure and the development almost stopped when the water content was close to the shrinkage limit. During the drying-wetting cycles，the new cracks did not always grow along the old tracks. In the drying-wetting cycle，the cracks of expansive soil developed gradually，the crack ratio and the total number of cracks were increased. The development of cracks ceased when it reached a certain stage. The iterative presence and healing of cracks significantly weakened the soil structure that resulted in the reduction of tensile energy. The volume of the cracks is 167.8 cm3 and about 4.8% of the total volume of the sample.

Key words： soil mechanics drying process rainfall evaporation expansive soil crack image recognition technique

引用本文:

曹玲1，2，王志俭2，张振华2. 降雨–蒸发条件下膨胀土裂隙演化特征试验研究[J]. 岩石力学与工程学报, 2016, 35(2): 413-421.
CAO Ling1，2，WANG Zhijian2，ZHANG Zhenhua2. Experimental research of cracking process of expansive soil under rainfall infiltration and evaporation. , 2016, 35(2): 413-421.

链接本文:

http://www.rockmech.org/CN/10.13722/j.cnki.jrme.2015.0028 或 http://www.rockmech.org/CN/Y2016/V35/I2/413

[7]	张家俊，龚壁卫，胡波，等. 干湿循环作用下膨胀土裂隙演化规律试验研究[J]. 岩土力学，2011，32(9)：2 729–2 734.(ZHANG Jiajun，GONG Biwei，HU Bo，et al. Study of evolution law of fissures of expansive clay under wetting and drying cycles[J]. Rock and Soil Mechanics，2011，32(9)：2 729–2 734.(in Chinese))
[8]	施斌，唐朝生，王宝军，等. 黏性土在不同温度下龟裂的发展及其机制讨论[J]. 高校地质学报，2009，15(2)：192–198.(SHI Bin，TANG Chaosheng，WANG Baojun，et al. Development and mechanism of desiccation cracking of clay soil under different temperatures[J]. Geological Journal of China Universities，2009，15(2)：192–198.(in Chinese)) " target="_blank">
[9]	VENKATARAMANA K，HANUMANTHA R B，SINGH D N，et al. Some investigations on cracking characteristics of soils[C]// Proceedings of the 12th IACMAG：Geomechanics in the Emerging Social and Technological Age. Goa，India：IACMAG，2008：1 532– 1 538. " target="_blank">
[15]	徐永福，黄寅春. 分形理论在研究非饱和土力学性质中的应用[J]. 岩土工程学报，2006，28(5)：635–638.(XU Yongfu，HUANG Yinchuan. Fractal-textured soils and their unsaturated mechanical properties[J]. Chinese Journal of Geotechnical Engineering，2006，28(5)：635–638.(in Chinese))
[2]	孔令伟，陈建斌，郭爱国，等. 大气作用下膨胀土边坡现场响应试验研究[J]. 岩土工程学报，2007，29(7)：1 065–1 073.(KONG Lingwei，CHEN Jianbin，GUO Aiguo，et al. Field response tests on expansive soil slopes under atmosphere[J]. Chinese Journal of Geotechnical Engineering，2007，29(7)：1 065–1 073.(in Chinese)) " target="_blank">
[6]	袁俊平，殷宗泽，包承纲. 膨胀土裂隙的量化手段与度量指标研究[J]. 长江科学院院报，2003，20(6)：27–30.(YUAN Junping，YIN Zongze，BAO Chenggang. Quantitative description method and index for fissures in expansive soils[J]. Journal of Yangtze River Scientific Research Institute，2003，20(6)：27–30.(in Chinese))
[17]	冉龙洲，宋翔东，唐朝生. 干燥过程中膨胀土抗拉强度特性研究[J]. 工程地质学报，2011，19(4)：620–625.(RAN Longzhou，SONG Xiangdong，TANG Chaosheng. Laboratorial investigation on tensile strength of expansive soil during drying[J]. Journal of Engineering Geology，2011，19(4)：620–625.(in Chinese))
[20]	FREDLUND D G，XING A Q. Equations for the soil-water characteristic curve[J]. Canadian Geotechnical Journal，1994，31(4)：521–532. " target="_blank">
[1]	包承刚. 非饱和土的性状及膨胀土边坡稳定问题[J]. 岩土工程学报，2004，26(1)：1–15.(BAO Chenggang. Behavior of unsaturated soil and stability of expansive soil slope[J]. Chinese Journal of Geotechnical Engineering，2004，26(1)：1–15.(in Chinese))
[3]	TERZAGHI K. Stability of slopes of natural clay[C]// Proceedings of the First International Conference on Soil Mechanics and Foundation Engineering. Cambridge：Harvard University，1936：161–165. " target="_blank">
[4]	GREGORY C H. On railway cutting and embankments：with an account of some slips in the London clay，on the line of the London and Croydon railway[J]. Minutes of the Proceedings，1844，3(1)：135–145. " target="_blank">
[5]	易顺民，黎志恒，张延中. 膨胀土裂隙结构的分形特征及其意义[J]. 岩土工程学报，1999，21(3)：294–298.(YI Shunmin，LI Zhiheng，ZHANG Yanzhong. The fractal characteristics of fractures in expansion soil and its significance[J]. Chinese Journal of Geotechnical Engineering，1999，21(3)：294–298.(in Chinese))
[10]	李雄威，冯欣，张勇. 膨胀土裂隙的平面描述分析[J]. 水文地质工程地质，2009，(1)：96–99.(LI Xiongwei，FENG Xin，ZHANG Yong. Depicting and analysis of expansive soil fissure in view of plane[J]. Hydrogeology and Engineering Geology，2009，(1)：96–99.(in Chinese))
[11]	卢再华，陈正汉，蒲毅彬. 原状膨胀土损伤演化的三轴CT试验研究[J]. 水利学报，2002，33(6)：106–112.(LU Zaihua，CHEN Zhenghan，PU Yibin. Study on damage evolution of natural expansive soil with computerized tomography during triaxial shear test[J]. Shuili Xuebao，2002，33(6)：106–112.(in Chinese))
[13]	石北啸，韩华强，宿辉. 膨胀土裂隙问题研究现状及展望[J]. 人民黄河，2014，36(2)：118–123.(SHI Beixiao，HAN Huaqiang，SU Hui. Research status and prospect of expansive soil crack problems[J]. Yellow River，2014，36(2)：118–123.(in Chinese))
[14]	曹玲，王志俭. 土体表面干缩裂隙的形态参数定量分析方法[J]. 长江科学院院报，2014，31(4)：63–67.(CAO Ling，WANG Zhijian. A quantitative analysis method for morphological parameter of the surface cracking in clay[J]. Journal of Yangtz River Scientific Research Institute，2014，31(4)：63–67.(in Chinese))
[18]	PERON H，HUECKEL T，LALOUI L，et al. Fundamentals of desiccation cracking of fine-grained soils：experimental characterization and mechanisms identification[J]. Canadian Geotechnical Journal，2009，46：1 177–1 201. " target="_blank">
[19]	栾茂田，汪东林，杨庆，等. 非饱和重塑土的干燥收缩试验研究[J]. 岩土工程学报，2008，30(1)：118–122.(LUAN Maotian，WANG Donglin，YANG Qing，et al. Experimental study on drying shrinkage of unsaturated compacted soils[J]. Chinese Journal of Geotechnical Engineering，2008，30(1)：118–122.(in Chinese))
[12]	赵明阶，徐蓉. 岩石损伤特性与强度的超声波速研究[J]. 岩土工程学报，2000，22(6)：720–722.(ZHAO Mingjie，XU Rong. The rock damage and strength study based on ultrasonic velocity[J]. Chinese Journal of Geotechnical Engineering，2000，22(6)：720–722.(in Chinese))
[16]	TRABELSI H，JAMEI M，ZENZRI H，et al. Crack patterns in clayey soils：experiments and modeling[J]. International Journal for Numerical and Analytical Methods in Geomechanics，2012，36(11)：1 410– 1 433. " target="_blank">