Creep properties and stability of sliding zone soil in Gapa landslide
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摘要: 水库滑坡变形破坏受其岩土体蠕变特性及环境因素的影响。当滑坡进入加速变形阶段后，变形骤然增大，失稳概率增加。为了研究滑坡岩土体蠕变特性及其稳定性，选取锦屏一级水电站呷爬滑坡为研究对象，采用坡表位移监测曲线分析与室内三轴蠕变试验相结合的方法，建立了Burgers蠕变模型结合FLAC3D软件进行了滑坡稳定性研究。分析坡表位移-时间曲线发现，坡体变形特征与一般滑坡土体的蠕变特征具有相似性，滑带土室内三轴蠕变试验结果表明，滑带土变形可划分为瞬时蠕变、减速蠕变与稳定蠕变3个阶段，同时其瞬时变形量、稳定蠕变速率均随围压以及应力水平的增大而增大。基于滑带土蠕变特性的Burgers蠕变模型的计算结果，对比了常规强度折减法与考虑蠕变的强度折减法的滑坡稳定性系数，计算结果表明呷爬滑坡目前处于稳定状态，在一个计算周期内考虑蠕变的强度折减法较常规强度折减法的稳定性系数下降了0.04，因此，揭示滑坡土体蠕变特性并在此基础上研究其稳定性具有实际意义。Abstract: Deformation and failure of reservoir landslide are affected by creep properties and environmental factors ofits rock and soil.Therefore, it is of great significance to study the creep properties and stability of landslide.In order to study the creep characteristics and stability of landslide rock and soil, taking Gapa landslide near Jinping Hydropower Station as the research object, combining the analysis of slope surface displacement monitoring curve with indoor triaxial creep test, and the Burgers creep model was established and FLAC3D software was used to study the stability of landslide.Analysis of the slope surface displacement-time curve shows that the deformation characteristics of the slope are similar to the creep characteristics of the general landslide soil.The indoor triaxial creep test shows that the deformation of the sliding zone soil can be divided into three stages:instantaneous creep, decelerating creep and stable creep.And its instantaneous deformation and stable creep rate increase with the increase of confining pressure and stress level.Based on the calculation results of the Burgers creep model based on the creep characteristics of the sliding zone soil, the stability coefficients of the conventional strength reduction method and the strength reduction method considering creep are compared.In one calculation cycle, the strength reduction method considering creep is reduced by 0.04 compared with the conventional strength reduction method.Therefore, it is of practical significance to reveal the creep properties of landslide soil and study its stability.
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Key words:
- sliding zone soil /
- triaxial creep test /
- Burgers model /
- stability evaluation /
- Gapa landslide
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图 3 呷爬滑坡坡表GNSS1、GNSS2位移监测曲线
Figure 3. Displacement monitoring curves of GNSS1 and GNSS2 on Gapa landslide
图 4 蠕变试验中加载完成后滑带土典型试样
Figure 4. Typical sample of sliding soil after loading during the creep test
图 5 zk03-2滑带土试样在不同围压下εa-t关系曲线图
Figure 5. εa-t curves of zk03-2 sliding zone soil under different confining pressure
图 6 zk03-2滑带土试样轴向应变速率图(以σ3=100 kPa, SL=0.3为例)
Figure 6. Axial deformation rate of zk03-2 sliding zone soil(σ3=100 kPa, SL=0.3)
图 8 Burgers模型示意图
E1.马克斯维尔体剪切模量；E2.开尔文体剪切模量；η1.马克斯维尔体黏滞系数；η2.开尔文体黏滞系数
Figure 8. Schematic diagram of Burgers model
图 9 zk03-2滑带土试样在不同围压(σ3)下蠕变曲线拟合
Figure 9. Fitting curves of zk03-2 sliding zone soil under different confining pressure
图 11 不同折减系数下监测点的位移
Figure 11. Monitoring point displacement under different reduction factors
图 12 不同折减系数下监测点位移-历时曲线
Figure 12. Monitoring point displacement-duration curve under different reduction factors
图 13 不同折减系数下剪应变增量图
Figure 13. Shear strain increment under different reduction factors
表 1 不同围压(σ3)、SL下zk03-2滑土样试样瞬时应变与稳定变形速率
Table 1. Transient deformation and steady creep speed under different confining pressure and stress level of zk03-2 sliding zone soil
围压σ3/kPa SL 0.30 0.45 0.60 0.75 瞬时应变 稳定变形速率/min-1 瞬时应变 稳定变形速率/min-1 瞬时应变 稳定变形速率/min-1 瞬时应变 稳定变形速率/min-1 100 0.004 58 1.60×10-7 0.009 18 3.08×10-7 0.018 18 5.50×10-7 0.028 66 8.91×10-7 200 0.005 41 2.78×10-7 0.010 73 4.77×10-7 0.016 67 7.66×10-7 0.031 01 1.03×10-6 300 0.005 98 3.57×10-7 0.011 81 6.20×10-7 0.016 51 8.60×10-7 0.030 90 1.28×10-6 400 0.008 12 3.58×10-7 0.013 65 6.06×10-7 0.022 22 1.01×10-6 0.035 53 1.54×10-6 
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表 2 拟合参数列表
Table 2. Fitting parameters
围压/kPa E1/MPa η1/(MPa·h-1) E2/MPa η2/(MPa·h-1) R2 100 20 157.897 00 19 591 400.000 54 608.033 00 326 203.593 0 0.984 73 17 159.254 07 1.43×107 42 258.768 44 227 175.942 7 0.977 43 11 097.550 15 1.15×107 32 030.466 25 198 310.954 8 0.985 46 9 141.695 65 8.66×106 24 845.012 94 148 786.078 2 0.983 48 200 25 836.852 62 1.55×107 49 118.586 90 326 490.067 3 0.988 28 19 978.666 10 1.30×107 41 221.297 17 254 029.300 4 0.985 29 16 740.971 64 1.11×107 36 158.216 02 238 143.437 3 0.984 94 11 636.111 63 1.08×107 31 093.727 70 210 060.380 8 0.989 58 300 28 659.285 41 1.10×107 76 439.008 25 468 256.890 1 0.973 82 22 197.039 11 1.32×107 39 880.660 78 222 172.353 6 0.983 21 20 595.783 21 1.26×107 38 466.849 77 225 903.365 3 0.989 09 14 856.919 12 1.08×107 31 683.157 55 193 088.289 2 0.986 53 400 27 210.916 94 2.03×107 57 110.154 52 400 494.822 5 0.988 67 24 259.076 69 1.74×107 51 340.454 75 354 264.185 4 0.987 88 19 871.911 70 1.35×107 42 253.295 25 289 869.722 9 0.986 05 15 827.433 53 1.10×107 32 718.215 79 203 406.816 0 0.985 27
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表 3 呷爬滑坡滑带土常规强度参数
Table 3. Routine strength parameters of sliding zone soil of Gapa landslide
E/MPa μ c/MPa φ/(°) γ/(g·cm-3) 堆积层 1 600 0.30 0.12 35 2.17 滑带 600 0.35 0.07 26 1.86 次级滑带 600 0.35 0.05 24 1.85 基岩 10 000 0.27 1.00 40 2.50 注：E.弹性模量；μ.泊松比；c.内聚力；φ.内摩擦角；γ.密度
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表 4 呷爬滑坡滑带土蠕变参数
Table 4. Creep parameters of sliding zone soil of Gapa landslide
E1/MPa η4/(MPa·h-1) E2/ MPa η2/(MPa·h-1) 滑带土 2.00×105 1.30×107 4.12×104 2.54×105
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[1] 蒋树, 王义锋, 唐川, 等.基于环剪试验的复活型低速滑坡活动机理[J].地质科技情报, 2019, 38(2):262-267. http://www.cnki.com.cn/Article/CJFDTotal-DZKQ201902030.htm [2] 孙淼军, 唐辉明, 王潇弘, 等.蠕动型滑坡滑带土蠕变特性研究[J].岩土力学, 2017, 38(2):385-391, 399. http://www.cnki.com.cn/Article/CJFDTotal-YTLX201702012.htm [3] 胡新丽, 孙淼军, 唐辉明, 等.三峡库区马家沟滑坡滑体粗粒土蠕变试验研究[J].岩土力学, 2014, 35(11):3163-3169, 3190. http://www.cnki.com.cn/Article/CJFDTotal-YTLX201411019.htm [4] 王琛, 胡德金, 刘浩吾, 等.三峡泄滩滑坡体滑动带土的蠕变试验研究[J].岩土力学, 2003, 24(6):1007-1010. http://d.wanfangdata.com.cn/Periodical/ytlx200503015 [5] 朱鸿鹄, 陈晓平, 程小俊, 等.考虑排水条件的软土蠕变特性及模型研究[J].岩土力学, 2006, 27(5):694-698. http://www.cnki.com.cn/Article/CJFDTotal-YTLX200605002.htm [6] 王志俭, 殷坤龙, 简文星, 等.三峡库区万州红层砂岩流变特性试验研究[J].岩石力学与工程学报, 2008, 28(4):840-847. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yslxygcxb200804026 [7] 卢萍珍, 曾静, 盛谦.软黏土蠕变试验及其经验模型研究[J].岩土力学, 2008, 29(4):1041-1044. http://www.cnki.com.cn/Article/CJFDTotal-YTLX200804038.htm [8] 蒋昱州, 张明鸣, 李良权.岩石非线性黏弹塑性蠕变模型研究及其参数识别[J].岩石力学与工程学报, 2007, 27(4):832-839. http://www.cqvip.com/QK/96026X/20084/27489209.html [9] 蔡煜, 曹平.基于Burgers模型考虑损伤的非定常岩石蠕变模型[J].岩土力学, 2016, 37(增刊2):369-374. http://www.cnki.com.cn/Article/CJFDTotal-YTLX2016S2047.htm [10] 唐佳, 彭振斌, 何忠明.基于岩体蠕变试验的Burgers改进模型[J].中南大学学报:自然科学版, 2017, 48(9):2414-2424. http://d.wanfangdata.com.cn/Periodical/zngydxxb201709021 [11] 刘俊来.岩石变形机制与流变学研究的近期发展:显微构造、变形机制与流变学国际会议简介[J].地质科技情报, 1999, 18(3):3-5. http://www.cqvip.com/Main/Detail.aspx?id=3766567 [12] 罗文强, 张倬元, 黄润秋.边坡系统稳定性的可靠性研究[J].地质科技情报, 1999, 18(2):62-64. http://d.wanfangdata.com.cn/Periodical/dzkjqb199902015 [13] 魏学勇, 欧阳祖熙, 董东林, 等.库水位涨落条件下滑坡渗流场特征及稳定性分析[J].地质科技情报, 2011, 30(6):128-132. http://d.wanfangdata.com.cn/Periodical/dzkjqb201106019 [14] 张俞, 殷坤龙, 郭子正, 等.库水位变动联合降雨作用下麻柳林滑坡稳定性评价[J].地质科技情报, 2019, 38(6):198-205. http://www.cnki.com.cn/Article/CJFDTotal-DZKQ201906024.htm [15] Cong L, Hu X.Triaxial rheological property of sandstone under low confining pressure[J/OL].Engineering Geology, 2017, 231: 45-55. [16] 张志沛, 王芝银, 彭惠.陕南泥岩三轴压缩蠕变试验及其数值模拟研究[J].水文地质工程地质, 2011, 38(1):53-58. http://d.wanfangdata.com.cn/Periodical/swdzgcdz201101010 [17] 丁秀丽, 付敬, 刘建, 等.软硬互层边坡岩体的蠕变特性研究及稳定性分析[J].岩石力学与工程学报, 2005, 25(19):12-20. http://www.cnki.com.cn/Article/CJFDTotal-YSLX200519001.htm [18] 谭红霞, 杨宇.考虑土流变的土坡稳定性分析方法研究[J].湘潭大学自科学报, 2005, 27(2):77-79, 97. http://d.wanfangdata.com.cn/Periodical/xtdx200502017 [19] 张岩岩, 文海家, 麻超超, 等.基于多源数据的蔡家坝特大型滑坡成因机制研究及稳定性评价[J].岩石力学与工程学报, 2018, 37(9):2048-2063. http://www.cnki.com.cn/Article/CJFDTotal-YSLX201809005.htm [20] 范志强, 唐辉明, 谭钦文, 等.滑带土环剪试验及其对水库滑坡临滑强度的启示[J].岩土工程学报, 2019, 41(9):1698-1706. http://www.cnki.com.cn/Article/CJFDTotal-YTGC201909016.htm [21] 丛璐.侏罗系砂泥岩互层岩体流变特性及其对抗滑桩嵌固效果影响研究[D].武汉: 中国地质大学(武汉), 2018 [22] 陈卫兵, 郑颖人, 冯夏庭, 等.考虑岩土体流变特性的强度折减法研究[J].岩土力学, 2008, 29(1):101-105. http://www.cnki.com.cn/Article/CJFDTotal-YTLX200801021.htm -
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