压实黄土土水特征对其孔隙结构的响应

doi:10.13722/j.cnki.jrme.2021.0820

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Abstract Dry density and moulding water content are two key factors affecting the soil-water characteristic curve of compacted loess. This paper aims to study the influence of the dry density and the moulding water content on the macroscopic soil-water characteristics of compacted loess from microscopic perspective. For this purpose，the filled loess of Yan'an was collected，and two sets of samples were made by static pressure method. The moulding water content of group A with different dry densities of 1.40 g/cm3，1.60 g/cm3 and 1.80 g/cm3 is 10%，and the dry density of group B with different moulding water contents of 10%，16%(optimal water content) and 18% is the maximum(equal to 1.79 g/cm3). In the study，the contact filter paper method was used to measure the full range of wetting soil-water characteristic curves，the SEM images were obtained using polished slices of epoxy-filling soil samples，and the pore distribution curves were measured by the mercury intrusion method. The test results show that the soil-water characteristic curves of the soil samples with different dry densities in group A basically overlap in the residual stage but present regular changes in the near saturated stage and the transition stage. The soil-water characteristic curves of group B also basically overlap in the residual stage，but that，with increasing the moulding water content，the air occlusion value decreases and the suction range of the transition zone widens，resulting in a change from a single wetting mode to a dual wetting mode in the transition stage. Through micro-structure analysis，it is found that the soil-water characteristics of the two sets of samples are essentially controlled by the pore size distribution and that there is a corresponding relationship between the coincident point and the intersection point of soil-water characteristic curves and pore distribution curves. The distribution range of the dominant pores determines the suction range of the transition stage，and the size of the dominant pores determines the wetting rate in the transition stage. The number of peaks(single or double peak) of the pore distribution curve determines the wetting mode(single or double dual wetting mode) of soil-water characteristics，and the coincident pore area curves determine the similar soil-water characteristic curves.

Key words： soil mechanics compacted loess soil dry density moulding water content soil water characteristics pore structure

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	WANG Yu1
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	LI Tonglu1
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	LEI Yulu1
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	LI Yan1
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Cite this article:

WANG Yu1,2,LI Tonglu1, et al. Responding of soil-water characteristics of compacted loess soil to its pore structure[J]. , 2022, 41(6): 1246-1255.

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https://rockmech.whrsm.ac.cn/EN/10.13722/j.cnki.jrme.2021.0820 OR https://rockmech.whrsm.ac.cn/EN/Y2022/V41/I6/1246

[1] 袁胜洋，刘先峰，潘高峰，等. 压实膨胀土压实特性试验研究[J]. 岩石力学与工程学报，2021，40(增1)：2 913–2 922.(YU Shengyang，LIU Xianfeng，PAN Gaofeng，et al. Compaction behavior of compacted Maryland expansive soil considering micro structure effect[J]. Chinese Journal of Rock Mechanics and Engineering，2021，40(Supp.1)：2 913–2 922.(in Chinese)) [2] 张茂省，谭新平，董英. 黄土高原平山造地工程环境效应浅析—以延安新区为例[J]. 地质论评，2019，65(6)：1 409–1 421.(ZHANG Maosheng，TAN Xinping，DONG Ying. Initial analysis on environmental effect of cutting hills to backfill ditch project on Loess Plateau—Take Yan'an New District as an example[J]. Geological Review，2019，65(6)：1 409–1 421.(in Chinese)) [3] WEN B，YAN Y. Influence of structure on shear characteristics of the unsaturated loess in Lanzhou，China[J]. Engineering Geology，2014，168：46–58. [4] LU N，LIKOS W J. Suction stress characteristic curve for unsaturated soil[J]. Journal of Geotechnical and Geoenvironmental Engineering，2006，132(2)：131–142. [5] FREDLUND D G. Unsaturated soil mechanics in engineering practice[J]. Journal of Geotechnical and Geoenvironmental Engineering，2006，132(3)：286–321. [6] VANAPALLI S K，FREDLUND D G，PUFAHL D E. Influence of soil structure and stress history on the soil-water characteristics of a compacted till[J]. Géotechnique，2001，51(6)：573–576. [7] 王铁行，郝延周，汪朝，等. 干湿循环作用下压实黄土动强度性质试验研究[J]. 岩石力学与工程学报，2020，39(6)：167–176. (WANG Tiehang，HAO Yanzhou，WANG Zhao，et al. Experimental study on dynamic strength properties of compacted loess under wetting-drying cycles[J]. Chinese Journal of Rock Mechanics and Engineering，2020，39(6)：167–176.(in Chinese)) [8] 高游，孙德安，张俊然，等. 考虑孔隙比和水力路径影响的非饱和土土水特性研究[J]. 岩土工程学报，2019，41(12)：25–30.(GAO You，SUN Dean，ZHANG Junran，et al. Soil-water characteristics of unsaturated soils considering initial void ratio and hydraulic path[J]. Chinese Journal of Geotechnical Engineering，2019，41(12)：25–30.(in Chinese)) [9] 郑方，刘奉银，王磊. 粒度对非饱和土土水特征曲线滞回特性的影响[J]. 水利与建筑工程学报，2019，17(5)：19–24.(ZHENG Fang，LIU Fengyin，WANG Lei. Influence of unsaturated soil granularity on hysteretic behavior of soil-water characteristic curve[J]. Journal of Water Resources and Architectural Engineering，2019，17(5)：19–24.(in Chinese)) [10] HOU X，VANAPALLI S K，LI T. Water infiltration characteristics in loess associated with irrigation activities and its influence on the slope stability in Heifangtai loess highland，China[J]. Engineering Geology，2017，234：27–37. [11] BHARAT T V，GAPAK Y. Soil water characteristics curve of bentonites in isochoric conditions during wetting：measurement and prediction[J]. Canadian Geotechnical Journal，2020，58(5)：711–721. [12] 李华，李同录，江睿君，等. 基于滤纸法的非饱和渗透性曲线测试[J]. 岩土力学，2020，41(3)：895–904.(LI Hua，LI Tonglu，JIANG Ruijun，et al. Measurement of unsaturated permeability curve using filter paper method[J]. Rock and Soil Mechanics，2020，41(3)：895–904. (in Chinese)) [13] AL-KHAFAF S，HANKS R J. Evaluation of the filter paper method for estimating soil water potential[J]. Soil Science，1974，117(4)：194–199. [14] JIANG Y，CHEN W，WANG G，et al. Influence of initial dry density and water content on the soil-water characteristic curve and suction stress of a reconstituted loess soil[J]. Bulletin of Engineering Geology and the Environment，2017，76(3)：1 085–1 095. [15] 刘小文，常立君，胡小荣. 非饱和红土基质吸力与含水率及密度关系试验研究[J]. 岩土力学，2009，30(11)：3 302–3 306.(LIU Xiaowen，CHANG Lijun，HU Xiaorong. Experimental research of matric suction with water content and dry density of unsaturated laterite[J]. Rock and Soil Mechanics，2009，30(11)：3 302–3 306.(in Chinese)) [16] 李云丽，卜书文，李婕，等. 干密度对非饱和压实黄土状粉土土水特征曲线的影响[J]. 科技通报，2021，37(4)：94–98.(LI Yunli，BU Shuwen，LI Jie，et al. Effect of dry density on soil water characteristic curve of unsaturated compacted loessial silt[J]. Bulletin of Science and Technology，2021，37(4)：94–98.(in Chinese)) [17] 蔡国庆，张策，李舰. 考虑初始干密度影响的SWCC预测方法研究[J]. 岩土工程学报，2018，40(增2)：27–31.(CAI Guoqing，ZHANG Ce，LI Jian. Prediction method for SWCC considering initial dry density[J]. Chinese Journal of Geotechnical Engineering，2018，40(Supp.2)：27–31.(in Chinese)) [18] MIGUEL M G，BONDER B H. Soil-water characteristic curves obtained for a colluvial and lateritic soil profile considering the macro and micro Porosity[J]. Geotechnical and Geological Engineering，2012，30(6)：1 405–1 420. [19] 刘奉银，张昭，周冬. 密度和干湿循环对黄土土–水特征曲线的影响[J]. 岩土力学，2011，32(增2)：132–136.(LIU Fengyin，ZHANG Zhao，ZHOU Dong，et al. Effects of initial density and drying-wetting cycle on soil water characteristic curve of unsaturated loess[J]. Rock and Soil Mechanics，2011，32(Supp.2)：132–136.(in Chinese)) [20] 陶高梁，孔令伟. 不同初始孔隙比土体进气值及土–水特征曲线预测[J]. 岩土工程学报，2018，40(增1)：34–38.(TAO Gaoliang，KONG Lingwei. Prediction of air-entry value and soil-water characteristic curve of soils with different initial void ratios[J]. Chinese Journal of Geotechnical Engineering，2018，40(Supp.1)：34–38.(in Chinese)) [21] BIRLE E. Effect of initial water content and dry density on the pore structure and the soil-water retention curve of compacted clay[C]// Unsaturated Soils：Research and Applications. Berlin，Heidelberg：Springer，2012：145–152. [22] ZHANG X，MAVROULIDOU M，GUNN M J. A study of the water retention curve of lime-treated London Clay[J]. Acta Geotechnica，2017，12(1)：23–45. [23] 刘丽，吴羊，李旭，等. 压实度对宽级配土水力特性的影响研究[J]. 岩土力学，2021，42(9)：2 545–2 555.(LIU Li，WU Yang，LI Xu，et al. Influence of compaction on hydraulic properties of widely-graded soil[J]. Rock and Soil Mechanics，2021，42(9)：2 545–2 555.(in Chinese)) [24] 庄心善，彭伟珂. 不同干密度下土水特征曲线模型参数确定简化方法[J]. 长江科学院院报，2019，36(3)：64–67.(ZHUANG Xingshan，PENG Weike. A simplified method for determining the model parameters of soil-water characteristic curve under different dry densities[J]. Journal of Yangtze River Scientific Research Institute，2019，36(3)：64–67.(in Chinese)) [25] WANG Y，LI T，LI P，et al. Measurement and uniform formulation of soil-water characteristic curve for compacted loess soil with different dry densities[J]. Advances in Civil Engineering，2021，21(6)：680–689. [26] 王娟娟，郝延周，王铁行. 非饱和压实黄土结构特性试验研究[J]. 岩土力学，2019，40(4)：1 351–1 357.(WANG Juanjuan，HAO Yanzhou，WANG Tiexing. Experimental study of structural characteristics of unsaturated compacted loess[J]. Rock and Soil Mechanics，2019，40(4)：1 351–1 357.(in Chinese)) [27] 任克彬，王博，李新明. 制样方法对粉土力学特性及孔隙特征的影响[J]. 岩石力学与工程学报，2019，38(4)：842–851.(REN Kebin，WANG Bo，LI Xingming，et al. Influence of the compaction procedure on mechanical behaviors and pore characteristics of silts[J]. Chinese Journal of Rock Mechanics and Engineering，2019，38(4)：842–851.(in Chinese)) [28] 高凌霞，栾茂田，杨庆. 非饱和重塑黏土渗透性试验研究[J]. 岩土力学，2008，29(8)：2 267–2 270.(GAO Lingxia，LUAN Maotian， YANG Qing. Experimental study of permeability of unsaturated remoulded clays[J]. Rock and Soil Mechanics，2008，29(8)：2 267– 2 270.(in Chinese)) [29] HOU X K，QI S W，LI T L，et al. Microstructure and soil-water retention behavior of compacted and intact silt loess[J]. Engineering Geology，2020，277：105814. [30] LI X A，LI L C，SONG Y X，et al. Characterization of the mechanisms underlying loess collapsibility for land-creation project in Shaanxi Province，China-a study from a micro perspective[J]. Engineering Geology，2019，249：77–88. [31] 丁自伟，李小菲，唐青豹，等. 砂岩颗粒孔隙分布分形特征与强度相关性研究[J]. 岩石力学与工程学报，2020，39(9)：64–73.(DING Ziwei，LI Xiaofei，TANG Qingbao，et al. Study on correlation between fractal characteristics of pore distribution and strength of sandstone particles[J]. Chinese Journal of Rock Mechanics and Engineering，2020，39(9)：64–73.(in Chinese)) [32] 李华，李同录，张亚国. 不同干密度压实黄土的非饱和渗透性曲线特征及其与孔隙分布的关系[J]. 水利学报，2020，51(8)：101–108.(LI Hua，LI Tonglu，ZHANG Yaguo，et al. Relationship between unsaturated permeability curve and pore-size distribution of compacted loess with different dry density[J]. Journal of Hydraulic Engineering，2020，51(8)：101–108.(in Chinese)) [33] 李燕，李同录，侯晓坤，等. 用孔隙分布曲线预测压实黄土非饱和渗透曲线及其适用范围的探讨[J]. 岩土力学，2021，42(9)：2 395–2 404.(LI Yan，LI Tonglu，HOU Xiaokun，et al. Prediction of unsaturated permeability curve of compaction loess with pore-size distribution curve and its application scope[J]. Rock and Soil Mechanics，2021，42(9)：2 395–2 404.(in Chinese)) [34] OUALMAKRAN M，MERCATORIS B，FRAN?OIS B. Pore size distribution of a compacted silty soil after compaction，saturation and loading[J]. Canadian Geotechnical Journal，2016，53(12)：1 902–1 909. [35] SHEPARD F P. Nomenclature based on sand-silt-clay ratios[J]. Journal of Sedimentary Research，1954，24(3)：151–158. [36] ASTM. Standard test method for measurement of soil potential (Suction) using filter paper. ASTM standard D5298–10[S]. [S. l.]：American Society For Testing And Materials W C P，2011. [37] FREDLUND D G，XING A，HUANG S. Predicting the permeability function for unsaturated soils using the soil-water characteristic curve[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1994，32(4)：159A.