-
摘要:
黏土的抗拉强度是决定土质边坡稳定的重要因素之一。由于土体的碎散性，使得黏土抗拉强度的研究一直进展较为缓慢。基于自行设计研发的直接拉伸试验装置对重塑黏土进行单轴拉伸试验，开展含水率和拉伸速率对重塑黏土抗拉强度影响规律的研究，并使用离散元方法对试验结果进行了验证。试验结果表明：（1）当拉伸速率等其他条件不变时，随着含水率的增加，重塑黏土的抗拉强度呈现出先增大再减小的趋势，峰值抗拉强度出现在最优含水率附近；（2）当含水率等其他条件不变时，随着拉伸速率的增加，重塑黏土的抗拉强度逐渐增大；（3）在试验含水率范围（18%～24%）内，重塑黏土在试验过程中发生塑性变形，并在达到峰值拉伸强度后表现出软化的破坏规律；（4）使用离散元模拟方法对上述试验得到的结果进行对比分析，重塑黏土的抗拉强度变化与试验结果一致，验证了本文方法的正确性。研究成果可用于土质边坡的稳定性分析以及边坡防护的计算和设计。
Abstract:The tensile strength of clay is an important factor in determining the stability of soil slope. Due to the fragmentation of soil, the understanding of the tensile strength of clay is not clear. In this study, the uniaxial tensile test of remolded clay is carried out to analyze the influence of water content and tensile rate on the tensile strength of remolded clay based on the self-designed direct tensile test device. The test results show that: (1) The tensile strength of remolded clay increases first and then decreases with the increase of water content, as the other conditions (such as tensile rate) remain stable. The peak tensile strength occurs near the optimal water content. (2) The tensile strength of remolded clay increases with the increase of tensile rate, as other conditions such as water content remain unchanged. (3) In the water content range (18%–24%) of this study, the remolded clay undergoes plastic deformation under uniaxial tension, and shows softening failure law after reaching the peak tensile strength. (4) The discrete element simulation method is used to analyze and verify the results obtained from the above experiments. The results of this study can be used for the stability analysis of soil slope and the calculation and design of slope protection.
-
Key words:
- remolded clay /
- uniaxial tensile test /
- tensile strength /
- water content /
- tensile rate /
- discrete element
-
-
表 1 重塑黏土基本参数
Table 1. Basic parameters of the remolded clay
参数 土粒相对
密度最大干密度
/（g·cm−3）最优含水率
/%塑限
/%液限
/%塑性
指数取值 2.76 1.73 19 18.49 35.48 16.99 
下载: 导出CSV
表 2 试验方案
Table 2. Test schemes
组数 拉伸速率/（mm·min−1） 含水率/% 1 10.8 18 2 10.8 19 3 10.8 20 4 10.8 21 5 10.8 22 6 10.8 24 7 7.2 20 8 5.4 20 9 3.6 20
下载: 导出CSV
表 3 同一拉伸速率下不同含水率重塑黏土的单轴拉伸试验结果
Table 3. Uniaxial tensile test results of the remolded clay with different water contents at the same tensile rate
拉伸速率/
（mm·min−1）含水率/% 抗拉强度/kPa 峰值拉应变/% 10.8 18 11.18 0.59 10.8 19 13.64 0.75 10.8 20 13.20 0.92 10.8 21 12.64 0.97 10.8 22 12.14 1.02 10.8 24 11.08 1.14
下载: 导出CSV
表 4 20%含水率下不同拉伸速率重塑黏土的单轴拉伸试验结果
Table 4. Uniaxial tensile test results of the remolded clay with different tensile rates when the water content is 20%
含水率/% 拉伸速率/
（mm·min−1）抗拉强度/kPa 峰值拉应变/% 20 3.6 10.06 1.03 20 5.4 11.24 0.99 20 7.2 12.55 0.96 20 10.8 13.20 0.92
下载: 导出CSV
表 5 颗粒基本计算参数
Table 5. Basic calculation parameters of particles
参数项目 参数取值 颗粒切向刚度/（N·m−1） 1×105 颗粒法向刚度/（N·m−1） 1×105 黏结强度/kPa 24.09 颗粒密度/（kg·m−3） 2760 摩擦系数 0.35，0.45，0.55，0.65
下载: 导出CSV
-
[1] 陈林万,张晓超,裴向军,等. 降雨诱发直线型黄土填方边坡失稳模型试验[J]. 水文地质工程地质,2021,48(6):151 − 160. [CHEN Linwan,ZHANG Xiaochao,PEI Xiangjun,et al,Model test of the linear loess fill slope instability induced by rainfall[J]. Hydrogeology & Engineering Geology,2021,48(6):151 − 160. (in Chinese with English abstract)]
CHEN Linwan, ZHANG Xiaochao, PEI Xiangjun, et al, Model test of the linear loess fill slope instability induced by rainfall[J]. Hydrogeology & Engineering Geology, 2021, 48（6）: 151 − 160. （in Chinese with English abstract）
[2] 王磊,李荣建,杨正午,等. 强降雨作用下黄土陡坡开裂特性测试[J]. 吉林大学学报(地球科学版),2021,51(5):1338 − 1346. [WANG Lei,LI Rongjian,YANG Zhengwu,et al. Experimental study on cracking characteristics of loess steep slope under intensive rainfall[J]. Journal of Jilin University (Earth Science Edition),2021,51(5):1338 − 1346. (in Chinese with English abstract)]
WANG Lei, LI Rongjian, YANG Zhengwu, et al. Experimental study on cracking characteristics of loess steep slope under intensive rainfall[J]. Journal of Jilin University （Earth Science Edition）, 2021, 51（5）: 1338 − 1346. （in Chinese with English abstract）
[3] 孙萍萍,张茂省,江睿君,等. 降雨诱发浅层黄土滑坡变形破坏机制[J]. 地质通报,2021,40(10):1617 − 1625. [SUN Pingping,ZHANG Maosheng,JIANG Ruijun,et al. Deformation and failure mechanism of rainfall-induced shallow loess landslide
J]. Geological Bulletin of China,2021,40(10):1617 − 1625. (in Chinese with English abstract)
[4] 杨志华,郭长宝,吴瑞安,等. 青藏高原巴塘断裂带地震滑坡危险性预测研究[J]. 水文地质工程地质,2021,48(5):91 − 101. [YANG Zhihua,GUO Changbao,WU Ruian,et al. Predicting seismic landslide hazard in the Batang fault zone of the Qinghai-Tibet Plateau[J]. Hydrogeology & Engineering Geology,2021,48(5):91 − 101. (in Chinese with English abstract)]
YANG Zhihua, GUO Changbao, WU Ruian, et al. Predicting seismic landslide hazard in the Batang fault zone of the Qinghai-Tibet Plateau[J]. Hydrogeology & Engineering Geology, 2021, 48（5）: 91 − 101. （in Chinese with English abstract）
[5] 李彩虹,李雪,郭长宝,等. 青藏高原东部鲜水河断裂带地震滑坡危险性评价[J]. 地质通报,2022,41(8):1473 − 1486. [LI Caihong,LI Xue,GUO Changbao,et al. Seismic landslide hazards assessment along the Xianshuihe fault zone,Tibetan Plateau,China[J]. Geological Bulletin of China,2022,41(8):1473 − 1486. (in Chinese with English abstract)]
LI Caihong, LI Xue, GUO Changbao, et al. Seismic landslide hazards assessment along the Xianshuihe fault zone, Tibetan Plateau, China[J]. Geological Bulletin of China, 2022, 41（8）: 1473 − 1486. （in Chinese with English abstract）
[6] 王涛,刘甲美,栗泽桐,等. 中国地震滑坡危险性评估及其对国土空间规划的影响研究[J]. 中国地质,2021,48(1):21 − 39. [WANG Tao,LIU Jiamei,LI Zetong,et al. Seismic landslide hazard assessment of China and its impact on national territory spatial planning[J]. Geology in China,2021,48(1):21 − 39. (in Chinese with English abstract)]
WANG Tao, LIU Jiamei, LI Zetong, et al. Seismic landslide hazard assessment of China and its impact on national territory spatial planning[J]. Geology in China, 2021, 48（1）: 21 − 39. （in Chinese with English abstract）
[7] 成永刚,吴六政,赵晓彦. 高速公路路堤滑坡成因及治理方案研究[J]. 铁道工程学报,2015,32(9):25 − 29. [CHENG Yonggang,WU Liuzheng,ZHAO Xiaoyan. Research on the cause of expressway embankment landslides and their treatment scheme[J]. Journal of Railway Engineering Society,2015,32(9):25 − 29. (in Chinese with English abstract)]
CHENG Yonggang, WU Liuzheng, ZHAO Xiaoyan. Research on the cause of expressway embankment landslides and their treatment scheme[J]. Journal of Railway Engineering Society, 2015, 32（9）: 25 − 29. （in Chinese with English abstract）
[8] 赵海军,马凤山,李志清,等. 喜马拉雅山区公路边坡崩滑灾害与防护措施破坏规律分析[J]. 工程地质学报,2022,30(3):656 − 671. [ZHAO Haijun,MA Fengshan,LI Zhiqing,et al. Geological hazards and protective measures of road slope in Himalayas Mountain Area[J]. Journal of Engineering Geology,2022,30(3):656 − 671. (in Chinese with English abstract)]
ZHAO Haijun, MA Fengshan, LI Zhiqing, et al. Geological hazards and protective measures of road slope in Himalayas Mountain Area[J]. Journal of Engineering Geology, 2022, 30（3）: 656 − 671. （in Chinese with English abstract）
[9] 汤连生,桑海涛,罗珍贵,等. 土体抗拉张力学特性研究进展[J]. 地球科学进展,2015,30(3):297 − 309. [TANG Liansheng,SANG Haitao,LUO Zhengui,et al. Advances in research on the mechanical behavior of the tensile strength of soils[J]. Advances in Earth Science,2015,30(3):297 − 309. (in Chinese with English abstract)]
TANG Liansheng, SANG Haitao, LUO Zhengui, et al. Advances in research on the mechanical behavior of the tensile strength of soils[J]. Advances in Earth Science, 2015, 30（3）: 297 − 309. （in Chinese with English abstract）
[10] THUSYANTHAN N I,TAKE W A,MADABHUSHI S P G,et al. Crack initiation in clay observed in beam bending[J]. Géotechnique,2007,57(7):581 − 594.
[11] VISWANADHAM B,JHA B,PAWAR S. Influence of geofibers on the flexural behavior of compacted soil beams[J]. Geosynthetics International,2010,17(2):86 − 99. doi: 10.1680/gein.2010.17.2.86
[12] AZMATCH T F,SEGO D C,ARENSON L U,et al. Tensile strength and stress–strain behaviour of Devon silt under frozen fringe conditions[J]. Cold Regions Science and Technology,2011,68(1/2):85 − 90.
[13] 李春清,梁庆国,吴旭阳,等. 重塑黄土抗拉强度试验研究[J]. 地震工程学报,2014,36(2):233 − 238. [LI Chunqing,LIANG Qingguo,WU Xuyang,et al. Study on the test of tensile strength of remolded loess[J]. China Earthquake Engineering Journal,2014,36(2):233 − 238. (in Chinese with English abstract)]
LI Chunqing, LIANG Qingguo, WU Xuyang, et al. Study on the test of tensile strength of remolded loess[J]. China Earthquake Engineering Journal, 2014, 36（2）: 233 − 238. （in Chinese with English abstract）
[14] 黄珂,姜冲,陈庆,等. 压实膨胀土抗拉强度试验研究[J]. 长江科学院院报,2017,34(6):93 − 96. [HUANG Ke,JIANG Chong,CHEN Qing,et al. Experimental study on tensile strength of compacted expansive soil[J]. Journal of Yangtze River Scientific Research Institute,2017,34(6):93 − 96. (in Chinese with English abstract)]
HUANG Ke, JIANG Chong, CHEN Qing, et al. Experimental study on tensile strength of compacted expansive soil[J]. Journal of Yangtze River Scientific Research Institute, 2017, 34（6）: 93 − 96. （in Chinese with English abstract）
[15] SHLOIDO G A. Determining the tensile strength of frozen ground[J]. Hydrotechnical Construction,1968,2(3):238 − 240. doi: 10.1007/BF02377405
[16] SOBHAN K,MASHNAD M. Tensile strength and toughness of soil-cement-fly-ash composite reinforced with recycled high-density polyethylene strips[J]. Journal of Materials in Civil Engineering,2002,14(2):177 − 184. doi: 10.1061/(ASCE)0899-1561(2002)14:2(177)
[17] ZHOU Guoqing,HU Kun,ZHAO Xiaodong,et al. Laboratory investigation on tensile strength characteristics of warm frozen soils[J]. Cold Regions Science and Technology,2015,113:81 − 90. doi: 10.1016/j.coldregions.2015.02.003
[18] AKIN I D,LIKOS W J. Brazilian tensile strength testing of compacted clay[J]. Geotechnical Testing Journal,2017,40:608 − 617. doi: 10.1520/GTJ20160180
[19] 李昊达,唐朝生,徐其良,等. 土体抗拉强度试验研究方法的进展[J]. 岩土力学,2016,37(增刊2):175 − 186. [LI Haoda,TANG Chaosheng,XU Qiliang,et al. Advances in experimental testing methods of soil tensile strength[J]. Rock and Soil Mechanics,2016,37(Sup 2):175 − 186. (in Chinese with English abstract)]
LI Haoda, TANG Chaosheng, XU Qiliang, et al. Advances in experimental testing methods of soil tensile strength[J]. Rock and Soil Mechanics, 2016, 37（Sup 2）: 175 − 186. （in Chinese with English abstract）
[20] 张辉,朱俊高,王俊杰,等. 击实砾质土抗拉强度试验研究[J]. 岩石力学与工程学报,2006,25(增刊2):4186 − 4190. [ZHANG Hui,ZHU Jungao,WANG Junjie,et al. Experimental study on tensile strength of compacted gravel soil[J]. Chinese Journal of Rock Mechanics and Engineering,2006,25(Sup 2):4186 − 4190. ( in Chinese with English abstract)]
ZHANG Hui, ZHU Jungao, WANG Junjie, et al. Experimental study on tensile strength of compacted gravel soil[J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25（Sup 2）: 4186 − 4190. （ in Chinese with English abstract）
[21] LU Ning,WU Bailin,TAN C P. Tensile strength characteristics of unsaturated sands[J]. Journal of Geotechnical and Geoenvironmental Engineering,2007,133(2):144 − 154. doi: 10.1061/(ASCE)1090-0241(2007)133:2(144)
[22] TAMRAKAR S B,MITACHI T,TOYOSAWA Y. Measurement of soil tensile strength and factors affecting its measurements[J]. Soils and Foundations,2007,47(5):911 − 918. doi: 10.3208/sandf.47.911
[23] 李建,唐朝生,王德银,等. 纤维加筋土的抗拉强度试验研究[J]. 工程地质学报,2012,20(增刊1):655 − 660. [LI Jian,TANG Chaosheng,WANG Deyin,et al. Experimental study on the tensile strength of fiber reinforced soil[J]. Journal of Engineering Geology,2012,20(Sup 1):655 − 660. (in Chinese with English abstract)]
LI Jian, TANG Chaosheng, WANG Deyin, et al. Experimental study on the tensile strength of fiber reinforced soil[J]. Journal of Engineering Geology, 2012, 20（Sup 1）: 655 − 660. （in Chinese with English abstract）
[24] 路立娜,樊恒辉,陈华,等. 分散性土单轴抗拉强度影响因素试验研究[J]. 岩土工程学报,2014,36(6):1160 − 1166. [LU Li’na,FAN Henghui,CHEN Hua,et al. Influencing factors for uniaxial tensile strength of dispersive soils[J]. Chinese Journal of Geotechnical Engineering,2014,36(6):1160 − 1166. (in Chinese with English abstract)]
LU Li’na, FAN Henghui, CHEN Hua, et al. Influencing factors for uniaxial tensile strength of dispersive soils[J]. Chinese Journal of Geotechnical Engineering, 2014, 36（6）: 1160 − 1166. （in Chinese with English abstract）
[25] 张绪涛,张强勇,高强,等. 土工直接拉伸试验装置的研制及应用[J]. 岩土工程学报,2014,36(7):1309 − 1315. [ZHANG Xutao,ZHANG Qiangyong,GAO Qiang,et al. Development and application of geotechnical direct tension test devices[J]. Chinese Journal of Geotechnical Engineering,2014,36(7):1309 − 1315. (in Chinese with English abstract)]
ZHANG Xutao, ZHANG Qiangyong, GAO Qiang, et al. Development and application of geotechnical direct tension test devices[J]. Chinese Journal of Geotechnical Engineering, 2014, 36（7）: 1309 − 1315. （in Chinese with English abstract）
[26] 张云,陈梦芸. 击实黏土抗拉强度研究[J]. 水文地质工程地质,2015,42(4):56 − 60. [ZHANG Yun,CHEN Mengyun. Tensile strength of compacted clay[J]. Hydrogeology & Engineering Geology,2015,42(4):56 − 60. (in Chinese with English abstract)]
ZHANG Yun, CHEN Mengyun. Tensile strength of compacted clay[J]. Hydrogeology & Engineering Geology, 2015, 42（4）: 56 − 60. （in Chinese with English abstract）
[27] 崔猛,韩尚宇,洪宝宁. 新型土工单轴拉伸试验装置的研制及应用[J]. 岩土力学,2017,38(6):1832 − 1840. [CUI Meng,HAN Shangyu,HONG Baoning. Development and application of a new geotechnical device for direct tension test[J]. Rock and Soil Mechanics,2017,38(6):1832 − 1840. (in Chinese with English abstract)]
CUI Meng, HAN Shangyu, HONG Baoning. Development and application of a new geotechnical device for direct tension test[J]. Rock and Soil Mechanics, 2017, 38（6）: 1832 − 1840. （in Chinese with English abstract）
[28] 胡磊,张云,史卜涛,等. 重塑黏土抗拉特性试验研究[J]. 水文地质工程地质,2017,44(4):98 − 104. [HU Lei,ZHANG Yun,SHI Butao,et al. Test research on the tensile properties of remoulded clay[J]. Hydrogeology & Engineering Geology,2017,44(4):98 − 104. (in Chinese with English abstract)]
HU Lei, ZHANG Yun, SHI Butao, et al. Test research on the tensile properties of remoulded clay[J]. Hydrogeology & Engineering Geology, 2017, 44（4）: 98 − 104. （in Chinese with English abstract）
[29] 蔡国庆,车睿杰,孔小昂,等. 非饱和砂土抗拉强度的试验研究[J]. 水利学报,2017,48(5):623 − 630. [CAI Guoqing,CHE Ruijie,KONG Xiaoang,et al. Experimental investigation on tensile strength of unsaturated fine sands[J]. Journal of Hydraulic Engineering,2017,48(5):623 − 630. (in Chinese with English abstract)]
CAI Guoqing, CHE Ruijie, KONG Xiaoang, et al. Experimental investigation on tensile strength of unsaturated fine sands[J]. Journal of Hydraulic Engineering, 2017, 48（5）: 623 − 630. （in Chinese with English abstract）
[30] 李梓月. 非饱和黏性土抗拉强度试验研究[D]. 武汉:湖北工业大学,2021. [LI Ziyue. Experimental study on tensile strength of unsaturated cohesive soil[D]. Wuhan:Hubei University of Technology,2021. (in Chinese with English abstract)]
LI Ziyue. Experimental study on tensile strength of unsaturated cohesive soil[D]. Wuhan: Hubei University of Technology, 2021. （in Chinese with English abstract）
[31] 张国华. 压实膨胀土的抗拉强度及拉-剪联合强度公式[J]. 铁道标准设计,2022,66(5):68 − 72. [ZHANG Guohua. Tensile strength and tensile-shear combined strength formula for compacted expansive soil[J]. Railway Standard Design,2022,66(5):68 − 72. (in Chinese with English abstract)]
ZHANG Guohua. Tensile strength and tensile-shear combined strength formula for compacted expansive soil[J]. Railway Standard Design, 2022, 66（5）: 68 − 72. （in Chinese with English abstract）
[32] 魏洪山,王伟志,徐永福,等. 水泥改良土的拉伸强度特性及其计算方法[J]. 水文地质工程地质,2022,49(6):81 − 89. [WEI Hongshan,WANG Weizhi,XU Yongfu,et al. Tensile strength characteristics and calculation methods of the cement stabilized soil[J]. Hydrogeology & Engineering Geology,2022,49(6):81 − 89. (in Chinese with English abstract)]
WEI Hongshan, WANG Weizhi, XU Yongfu, et al. Tensile strength characteristics and calculation methods of the cement stabilized soil[J]. Hydrogeology & Engineering Geology, 2022, 49（6）: 81 − 89. （in Chinese with English abstract）
[33] 中华人民共和国住房和城乡建设部. 土工试验方法标准:GB/T 50123—2019[S]. 北京:中国计划出版社,2019. [Ministry of Housing and Urban-Rural Development of the People’s Republic of China. Standard for geotechnical testing method:GB/T 50123—2019[S]. Beijing:China Planning Press,2019. (in Chinese)]
Ministry of Housing and Urban-Rural Development of the People’s Republic of China. Standard for geotechnical testing method: GB/T 50123—2019[S]. Beijing: China Planning Press, 2019. （in Chinese）
-
图(9)
表(5)
计量
- 文章访问数: 56
- PDF下载数: 0
- 施引文献: 0