干湿循环作用下古土壤细微观结构及宏观力学性能变化规律研究

doi:10.13722/j.cnki.jrme.2019.0291

摘要
图/表
参考文献
相关文章 (15)

全文: PDF (846 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要为了明确天然及干湿循环状态古土壤的细微观特性及力学性质变化情况，揭示细微观结构变化与宏观力学性质的相关关系，并区分古土壤与黄土间存在的差异性。基于此，从银西高铁早胜三号隧道取古土壤试样，分别利用X射线衍射、扫描电镜及核磁共振技术，从矿物成分、孔隙特征、接触形式及弛豫时间等几方面对不同条件下古土壤的细微观特征及力学特性进行了系统研究，并同黄土的已有研究成果进行了对比。认为：古土壤主要以石英、长石、方解石等矿物为主，在微观层面表现出凝块、集粒发育，以间接接触、面–面接触为主，微小孔隙占比较大，颗粒趋于类圆形，分布相对集中的特点。而在细观层面核磁共振结果表现为反演良好、三峰分布、一主两次的T2谱分布形式；但随着干湿循环的进行，粒间接触形式由面–面接触逐渐过渡为边–面接触，最后发展为边–边或点–面的形式。同时，微小孔隙所占比例逐渐减少，大中孔隙含量逐渐增加，颗粒丰度值不断增加，分形维数逐渐减小。在细观尺度上，T2谱主峰仍占到绝大多数，且随着循环次数增加，图谱峰值大致增加，谱图不断右移，谱面积逐渐增大，与循环次数呈现良好的相关关系。同时，微、细、宏观相互作用使得土体黏聚力、内摩擦角随干湿循环的进行表现出负相关关系，而无荷膨胀率则表现出一定的正相关；将试验结果与黄土试验结果对比，发现古土壤中石英含量较少，伊利石含量较多，方解石含量最多；微孔隙所占比例较大，小孔隙比例较小，大中孔隙含量相当；颗粒分布相对集中，形状趋于圆形。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	叶万军1
	2
	吴云涛1
	杨更社1
	景宏君1
	2
	常帅斌3
	陈明3

关键词 ：土力学, 古土壤, 干湿循环, X射线衍射, 扫描电镜, 核磁共振, 尺寸效应

Abstract：In order to make clear microscopic characteristics and mechanical property of natural paleosol and dry-wet cyclical paleosol，to reveal the correlation between microstructure change and macro-mechanical property and to distinguish the difference between paleosol and loess，the microscopic characteristics and mechanical properties of paleosol samples taken from Zaosheng tunnel No.3 of Yinchuan-Xi?an high-speed railway were systematically investigated under different conditions from the aspects of mineral component，porosity characters，contact form and relaxation time，adopting X-ray diffraction，scanning electron microscope and nuclear magnetic resonance，and comparisons were made with the existing research results on loess. Paleosol mainly containing quartz，feldspar and calcite shows some microscopic characteristics including coagulum and graining developing，indirect contact and surface-surface contact，a large proportion of tiny holes，quasi-circular grains and relative concentration of distribution. On the mesoscopic scale，the results of MRI show that paleosol has a T2 spectral distribution form with good inversions as well as one primary and two secondary peaks. With the proceeding of dry-wet circulation，intergranular contact form is gradually transited from surface-surface to side-surface and finally side-side or spot-surface Meanwhile，the proportion of micro holes gradually reduces accompanying with medium and large holes gradually increasing，the granular abundance value constantly increases and fractal dimension gradually decreases. On the mesoscopic scale，the main peak of T2 spectrum still takes a large proportion，and with increasing cycle number，the peak value of the spectrogram roughly increases and constantly moves right accompanying with the spectrum area gradually increasing. Due to the interaction of micro，fine and macro levels，both the cohesion and internal friction angle have a negative correlation with the number of dry-wet circulation，while the non-loading expansion rate has certain positive respondence. compared with loess，the content of quartz in paleosol is less，followed by illite and calcite，and the proportions of micro，small，and medium and large holes are respectively larger，smaller and same. The granular distribution of paleosol is relatively centralized and the shape tends to be round.

Key words： soil mechanics paleosol drying and wetting cycle X-ray diffraction scanning electron microscope nuclear magnetic resonance size effect

引用本文:

叶万军1，2，吴云涛1，杨更社1，景宏君1，2，常帅斌3，陈明3. 干湿循环作用下古土壤细微观结构及宏观力学性能变化规律研究[J]. 岩石力学与工程学报, 2019, 38(10): 2126-2137.
YE Wanjun1，2，WU Yuntao1，YANG Gengshe1，JING Hongjun1，2，CHANG Shuaibin3，CHEN Ming3. Study on microstructure and macro-mechanical properties of paleosol under dry-wet cycles. , 2019, 38(10): 2126-2137.

链接本文:

http://www.rockmech.org/CN/10.13722/j.cnki.jrme.2019.0291 或 http://www.rockmech.org/CN/Y2019/V38/I10/2126

[7]	李丽，张坤，张青龙，等. 干湿和冻融循环作用下黄土强度劣化特性试验研究[J]. 冰川冻土，2016，38(4)：1 142-1 149.(LI Li，ZHANG Kun，ZHANG Qinglong，et al. Experimental study on the loess strength degradation characteristics under the action of dry-wet and freeze-thaw cycles[J]. Journal of Glaciology and Geocryology，2016，38(4)：1 142-1 149.(in Chinese))
[16]	蒋明镜，李志远，黄贺鹏，等. 南海软土微观结构与力学特性试验研究[J]. 岩土工程学报，2017，39(增2)：17-20.(JIANG Mingjing，LI Zhiyuan，HUANG Hepeng，et al. Experimental study on microstructure and mechanical properties of seabed soft from South China sea[J]. Chinese Journal of Geotechnical Engineering，2017，39(Supp.2)：17-20.(in Chinese))
[17]	沈建华，汪稔，郑郧，等. 湛江组结构性黏土区域微观结构特性研究[J]. 岩土力学，2013，34(7)：1 931-1 936.(SHEN Jianhua，WANG Ren，ZHENG Yun，et al. Research on regional microstructure characteristics of structural clay of Zhanjiang formation[J]. Rock and Soil Mechanics，2013，34(7)：1 931-1 936.(in Chinese))
[20]	周科平，胡振襄，高峰，等. 基于核磁共振技术的大理岩三轴压缩损伤规律研究[J]. 岩土力学，2014，35(11)：3 117-3 122. (ZHOU Keping，HU Zhenxiang，GAO Feng，et al. Study of marble damage laws under triaxial compression condition based on nuclear magnetic resonance technique[J]. Rock and Soil Mechanics，2014，35(11)：3 117-3 122.(in Chinese))
[22]	周科平，胡振襄，李杰林，等. 基于核磁共振技术的大理岩卸荷损伤演化规律研究[J]. 岩石力学与工程学报，2014，33(增2)：3 523-3 530.(ZHOU Keping，HU Zhenxiang，LI Jielin，et al. Experimental research into nuclear magnetic resonance in marble with different initial damages under unloading conditions[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(Supp.2)：3 523-3 530.(in Chinese))
[24]	雷祥义. 中国黄土的孔隙类型与湿陷性[J]. 中国科学(B辑)，1987，12：1 309-1 316.(LIE Xiangyi. Pore types and collapsibility of loess in China[J]. Science in China Series B，1987，12：1 309-1 316.(in Chinese))
[4]	段涛. 干湿循环情况下黄土强度劣化特性研究[硕士学位论文][D]. 杨凌：西北农林科技大学，2009.(DUAN Tang. The research of alternating wet and dry on thedeterioration of loess strength[M. S. Thesis][D]. Yangling：Northwest A&F University，2009.(in Chinese))
[6]	李凌芸. 基于干湿循环的膨胀土工程特性试验研究[硕士学位论文][D]. 杨凌：西北农林科技大学，2015.(LI Linyun. Experimental study on the engineering characteristics of experimental study on the engineering characteristics of expansive soil under wetting-drying cycle[M. S. Thesis][D]. Yangling：Northwest A&F University，2015.(in Chinese))
[9]	刘文化，杨庆，唐小微，等. 干湿循环条件下不同初始干密度土体的力学行为[J]. 水利学报，2014，45(3)：261-268.(LIU Wenhua，YANG Qing，TANG Xiaowei，et al. Mechanical behaviors of soils with different initial dry densities under drying-wetting cycle[J]. Journal of Hydraulic Engineering，2014，45(3)：261-268.(in Chinese))
[10]	杨和平，张锐，郑健龙，等. 有荷条件下膨胀土的干湿循环胀缩变形及强度变化规律[J]. 岩土工程学报，2006，28(11)：1 936-1 941. (YANG Heping，ZHANG Rui，ZHENG Jianlong，et al. Variation of deformation and strength of expansive soil during cyclic wetting and drying under loading condition[J]. Chinese Journal of Geotechnical Engineering，2006，28(11)：1 936-1 941.(in Chinese))
[12]	曹玲，王志俭，张振华，等. 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 Ling，WANG Zhijian，ZHANG Zhenhua，et al. Experimental research of cracking process of expansive soil under rainfall infiltration and evaporation[J]. Chinese Journal of Rock Mechanics and Engineering，2016，35(2)：413-421.(in Chinese))
[14]	刘文化，杨庆，唐小微，等. 干湿循环条件下粉质黏土在循环荷载作用下的动力特性试验研究[J]. 水利学报，2015，46(4)：425-432.(LIU Wenhua，YANG Qing，TANG Xiaowei，et al. Experimental study on the dynamic characteristics of silt clay subjected to drying- wetting cycles under cyclic loading[J]. Journal of Hydraulic Engineering，2015，46(4)：425-432.(in Chinese))
[1]	陈留凤，彭华. 干湿循环对硬黏土的土水特性影响规律研究[J]. 岩石力学与工程学报，2016，35(11)：2 337-2 344.(CHEN Liufeng，PENG Hua. Experimental study on the water retention properties of the hard clay under cyclic suction conditions[J]. Chinese Journal of Rock Mechanics and Engineering，2016，35(11)：2 337-2 344.(in Chinese))
[2]	孙德安，黄丁俊. 干湿循环下南阳膨胀土的土水和变形特征[J]. 岩土力学，2015，36(增1)：115-119.(SUN De?an，HUANG Dingjun. Soilwater and deformations characteristics of Nanyang expansive soil after wetting-drying cycles[J]. Rock and Soil Mechanics，2015，36(Supp.1)：115-119.(in Chinese))
[3]	袁志辉. 干湿循环下黄土的强度及微结构变化机理研究[博士学位论文][D]. 西安：长安大学，2015.(YUAN Zhihui. Research on change mechanism of strength and microstructure of loess under wetting-drying cycle[Ph. D. Thesis][D]. Xi?an：Chang?an University，2015.(in Chinese))
[8]	孔令伟，周葆春，白颢. 荆门非饱和膨胀土的变形与强度特性试验研究[J]. 岩土力学，2010，31(10)：3 036-3 042.(KONG Lingwei，ZHOU Baochun，BAI Hao. Experimental study of deformation and strength characteristics of Jinmen unsaturated expansive soil[J]. Rock and Soil Mechanics，2010，31(10)：3 036-3 042.(in Chinese))
[18]	方祥位，申春妮，李春海，等. 陕西蒲城黄土微观结构特征及定量分析[J]. 岩石力学与工程学报，2013，32(9)：1 917-1 925.(FANG Xiangwei，SHEN Chunni，LI Chunhai，et al. Quantitative analysis of microstructure characteristics of pucheng loess in shaanxi province[J]. Chinese Journal of Rock Mechanics and Engineering，2013，32(9)： 1 917-1 925.(in Chinese))
[27]	叶万军，李长清，杨更社，等. 冻融环境下黄土体结构损伤的尺度效应[J]. 岩土力学，2018，39(7)：2 336-2 343.(YE Wanjun，LI Changqing，YANG Gengshe，et al. Scale effects of damage to loess structure under freezing and thawing conditions[J]. Rock and Soil Mechanics，2018，39(7)：2 336-2 343.(in Chinese))
[28]	杨更社，申艳军，贾海梁，等. 冻融环境下岩体损伤力学特性多尺度研究及进展[J]. 岩石力学与工程学报，2018，37(3)：545-563.(YANG Gengshe，SHEN Yanjun，JIA Hailiang，et al. Research progress and tendency in characteristics of multi-scale damage mechanics of rock under freezing-thawing[J]. Chinese Journal of Rock Mechanics and Engineering，2018，37(3)：545-563.(in Chinese))
[5]	王晓亮. 干湿循环对黄土抗剪强度和结构性及边坡稳定性影响的研究[硕士学位论文][D]. 西安：西安理工大学，2017.(WANG Xiaoliang. Research on the effect of shear strength and structural property and slope stability of loess under dry-wet cycle[M. S. Thesis][D]. Xi?an：Xi?an University of Technology，2017.(in Chinese))
[11]	王飞，李国玉，穆彦虎，等. 干湿循环条件下压实黄土变形特性试验研究[J]. 岩土力学，2016，37(8)：2 306-2 320.(WANG Fei，LI Guoyu，MU Yanhu，et al. Experimental study of deformation characteristics of compacted loess subjected to drying-wetting cycle[J]. Rock and Soil Mechanics，2016，37(8)：2 306-2 320.(in Chinese))
[13]	万勇，薛强，赵立业，等. 干湿循环对填埋压实黏土盖层渗透系数影响研究[J]. 岩土力学，2015，36(3)：679-693.(WAN Yong，XUE Qiang，ZHAO Liye，et al. Effects of wetting-drying cycles on permeability compacted clay cover at landfill site[J]. Rock and Soil Mechanics，2015，36(3)：679-693.(in Chinese))
[15]	王德银，唐朝生，李建，等. 干湿循环作用下膨胀土的贯入特性试验研究[J]. 岩土力学，2016，37(1)：57-75.(WANG Deyin，TANG Chaosheng，LI Jian，et al. An experimental study of penetration characteristics of expansive soil under wetting-drying cycles[J]. Rock and Soil Mechanics，2016，37(1)：57-75.(in Chinese))
[21]	周科平，苏淑华，胡振襄，等. 不同初始损伤下大理岩卸荷的核磁共振试验研究[J]. 岩土力学，2015，36(8)：2 144-2 150.(ZHOU Keping，SU Shuhua，HU Zhenxiang，et al. Experimental research into nuclear magnetic resonance in marble with different initial damages under unloading conditions[J]. Rock and Soil Mechanics，2015，36(8)：2 144-2 150.(in Chinese))
[23]	侯鑫，马巍，李国玉，等. 木质素磺酸盐对兰州黄土力学性质的影响[J]. 岩土力学，2017，38(增2)：18-26.(HOU Xin，MA Wei，LI Guoyu，et al. Influence of lignosulfonate on mechanical properties of Lanzhou loess[J]. Rock and Soil Mechanics，2017，38(Supp.2)：18-26.(in Chinese))
[25]	李秀娟. 裂缝及古土壤影响下黄土包气带水-气运移规律研究[硕士学位论文][D]. 西安：长安大学，2018.(LI Xiujuan. Study on water-air migration of loess aeration zone under the influence of cracks and paleosols[M. S. Thesis][D]. Xi?an：Chang?an university，2018.(in Chinese))
[19]	周科平，张亚民，李杰林，等. 冻融花岗岩细观损伤演化的核磁共振[J]. 中南大学学报：自然科学版，2013，44(8)：3 384-3 389. (ZHOU Keping，ZHANG Yamin，LI Jielin，et al. Granite microstructure deterioration characteristic under condition of freezing-thawing based on NMR technology[J]. Journal of Central South University：Science and Technology，2013，44(8)：3 384-3 389.(in Chinese))
[26]	钱程. 冻融作用下黑方台黄土力学特性及微细观结构变化研究[博士学位论文][D]. 北京：中国地质大学(北京)，2018.(QIAN Cheng. Study on the mechanical properties and structure changes in microscale and mesoscale of loess in Heifangtai under freeze-thaw action[Ph. D. Thesis][D]. Beijing：China University of Geosciences (Beijing)，2018.(in Chinese))