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EVOLUTION CHARACTERISTICS OF WEAK INTERCALATION IN MASSIVE LAYERED ROCKSLIDES-A CASE STUDY OF JIWEISHAN ROCKSLIDE IN WULONG, CHONGQING
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摘要: 软弱夹层经过长期地质历史演化，性质劣化后形成滑带，对大型层状基岩滑坡的稳定性起重要的控制作用。为了查清软弱夹层形成滑带的演化过程，以重庆武隆鸡尾山滑坡为例，对比研究了山体内软弱夹层的发育规律，将其划分为原生软岩、层间剪切带和滑带3个阶段，并通过岩矿组分含量、物理性质、微结构、物理化学性质和蠕变力学性质试验分析了3个阶段的演化特征。结果表明：从矿物成分演化过程来看，黏土矿物含量增加趋势明显，均值从4.4%增加到16.9%；从微结构演化过程来看，微结构由致密变得疏松，孔隙及节理裂隙增多，密度降低了5%~6%，孔隙率升高了108%；从物理化学性质演化过程来看，交换性盐基总含量在原岩中最高，其次是滑带，层间剪切带最低，有机质含量逐渐增大，整个演化环境呈弱碱性。从蠕变剪切强度演化过程来看，软弱夹层的内摩擦角由57.58°降低到29.63°，黏聚力由585 kPa降低到96 kPa。在此基础上，对鸡尾山滑坡驱动块体最大主剖面的下滑推力进行分析，下滑推力随着长期剪切强度参数的降低而增大，当内摩擦角φ < 25°，黏聚力c < 129 kPa时，下滑推力大于0，驱动块体失稳。该研究对受软弱夹层控制的层状基岩滑坡的发育发展过程、失稳机理研究提供了重要的借鉴意义。Abstract: The weak intercalation forms a sliding zone after long-term geological evolution and plays an important role in controlling the stability of massive layered rockslides. In order to determine the formation process of the sliding zone, we take the Jiweishan Landslide as an example and analyze the developmental regularities of the weak intercalation. The weak intercalation can be divided into three stages including the original soft rock, the interlayer shear zone and the sliding zone. In addition, we have comparatively studied the evolutionary characteristics of weak intercalation through the laboratory test of the physical properties, physicochemical properties, and physical mechanics properties. As a result, from the view of the mineral composition, the mean value of the clay mineral content is increased from 4.4% to 16.9%. From the view of the physical properties and the microstructure, the density is decreased from 5% to 6%, and the porosity is increased by 108%. It reflects the decreased density and loose structure due to long-term evolution. From the view of the physicochemical properties, the total content of exchangeable salt is the highest in the original soft rock, followed by the sliding zone, whereas the interlayer shear zone exhibited the lowest value. The organic matter content is gradually increased in the alkalescence evolutionary environment. From the view of the shear creep strength, the internal friction angle is decreased from 57.58°to 29.63°, and the cohesion decreased from 585 kPa to 96 kPa. Based on these data, we analyze the change of the residual sliding thrust of the main section of the Jiweishan Landslide driving block. The residual sliding thrust increases with a decrease in the long-term strength parameter. When the internal friction angle φ < 25° and cohesion c < 129 kPa, the residual sliding thrust of the driving block is greater than zero, and then the driving block is sliding. The conclusions provide an important reference for the study of the development and mechanism of layered rockslides controlled by weak intercalations.
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图 3 软弱夹层分布剖面图(Ⅰ-Ⅰ′)
Figure 3. Longitudinal profile Ⅰ-Ⅰ′ showing the distribution of the weak intercalations
图 8 鸡尾山型软弱夹层演化模式图
Figure 8. Pattern of the evolutionary stages in the Jiweishan weak intercalations
图 12 软弱夹层的蠕变剪切位移-时间曲线(σ=1.5 MPa)
a.原生软岩; b.层间剪切带; c.滑带
Figure 12. Creep curves of the weak intercalations(σ=1.5 MPa)
图 14 驱动块体主剖面的力学模型
Figure 14. Mechanics model of the main section for the driving block
图 15 驱动块体最大主剖面的下滑推力趋势图
Figure 15. Image showing the trend of the residual sliding thrust of the main section of the driving block
表 1 软弱夹层的矿物成分及含量演化过程
Table 1. Evolutionary process of mineral components and contents
演化阶段 矿物含量/% 石英 方解石 白云石 黄铁矿 黄钾铁矾 滑石 蒙脱石 绿泥石 原生软岩 14.9 47.7 32.9 0.2 — 2.3 0.9 1.2 层间剪切带 14.7 61.7 14.6 0.6 — 3.6 3.2 1.5 滑带 15.3 53.5 5.6 0.5 8.2 5.8 7.3 3.8 
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表 2 软弱夹层物理化学性质演化过程
Table 2. Evolutionary process of physicochemical property
演化阶段 交换盐基总量/meq·100g-1 阳离子/meq·100g-1 有机质/% pH K+ Ca2+ Na+ Mg2+ Al3+ Fe3+ 原生软岩 3.403 0.052 2.343 0.082 0.911 0.012 0.003 1.31 9.21 层间剪切带 2.294 0.109 1.437 0.089 0.633 0.017 0.009 1.38 9.03 滑带 2.804 0.051 1.833 0.084 0.818 0.014 0.004 2.33 8.65 meq为毫克当量
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表 3 软弱夹层的剪切蠕变试验方案
Table 3. Scheme of the weak intercalations shear creep test
演化阶段 正应力σ/MPa 剪切面积A/cm2 分级剪应力q/MPa 1 2 3 4 5 6 原生软岩 0.7 359 0.489 0.869 1.307 1.722 2.173 — 1.5 320 0.669 1.513 2.262 2.909 3.835 — 2.3 538 0.839 1.732 2.436 3.351 4.221 4.952 层间剪切带 0.7 312 0.221 0.424 0.655 0.858 1.079 1.301 1.5 291 0.500 1.000 1.375 1.468 — — 2.3 347 0.839 1.257 1.691 2.009 2.518 2.922 滑带 0.5 272 0.112 0.187 0.284 0.385 0.586 — 1.0 251 0.247 0.488 0.738 0.899 — — 1.5 298 0.330 0.680 1.020 1.330 — —
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表 4 软弱夹层长期剪切强度参数
Table 4. Parameters of long term shear strength
演化阶段 正应力σ /MPa 长期剪切强度/MPa φ /(°) c /MPa 原生软岩 0.7 1.725 57.6 0.585 1.5 2.909 2.3 4.218 层间剪切带 0.7 1.080 42.0 0.318 1.5 1.375 2.3 2.500 滑带 0.5 0.423 29.6 0.096 1.0 0.651 1.5 0.964
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Broili L. 1967. New knowledge on the geomorphology of the vajont slide slipe surface[J]. Felsmechanik und Ingenieurgeologie, 5(1):38-88. Feng Z, Yin Y P, Li B, et al. 2012. Mechanism analysis of apparent dip landslide of Jiweishan in Wulong, Chongqing[J]. Rock and Soil Mechanics, 33(9):2704-2712. http://en.cnki.com.cn/Article_en/CJFDTOTAL-YTLX201209027.htm Fleming R W, Ellen S D, Algus M A. 1989. Transformation of dilative and contractive landslide debris into debris flows-an example from Marin County, California[J]. Engineering Geology, 27(1-4):201-223. doi: 10.1016/0013-7952(89)90034-3 Gao Y, Li B, Wang G Z. 2016. Motion feature and numerical simulation analysis of Jiweishan landslide with rapid and long run-out[J]. Journal of Engineering Geology, 24(3):425-434. http://www.en.cnki.com.cn/Article_en/CJFDTotal-GCDZ201603013.htm Lan H X, Chen J H, Wu Y M. 2018. Spatial characterization of micro-and nanoscale micro-cracks in gas shale before and after triaxial compression test[J]. Journal of Engineering Geology, 26(1):24-35. http://d.old.wanfangdata.com.cn/Periodical/gcdzxb201801004 Lan Z Y, Zhao J J, Zhai C, et al. 2014. Failure mechanism of slopes with soft base from numerical simulation[J]. Journal of Engineering Geology, 22(3):421-427. http://en.cnki.com.cn/Article_en/CJFDTOTAL-GCDZ201403013.htm Müller L. 1964. The rock slide in the Vajont Valley[J]. Rock Mechanics and Engineering Geology, 2(3-4):148-212. Müller L. 1968. New considerations on the Vaiont slide[J]. Rock Mechanics and Engineering Geology, 6(1-2):1-91. https://trid.trb.org/view.aspx?id=127263 Müller L. 1987. The vajont catastrophe-a personal review[J]. Engineering Geology, 24(1-4):423-444. https://www.sciencedirect.com/science/article/pii/0013795287900780 Li S D, Li X, Zhang N X, et al. 2006. Water-rock interaction of clay gouged intercalation sludging process of baota landslides in Three Gorges reservoir area[J]. Rock and Soil Mechanics, 27(10):1841-1846. http://d.wanfangdata.com.cn/Periodical/ytlx200610041 Li X, Li S D, Chen J, et al. 2008. Coupling effect mechanism of endogenic and exogenic geological processes of geological hazards evolution[J]. Chinese Journal of Rock Mechanics and Engineering, 27(9):1792-1806. http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSLX200809008.htm Liao Q L, Li X, Li S D, et al. 2005. Occurrence, geology and geomorphy characteristics and origin of Qianjiangping landslide in three gorges reservoir area and study on ancient landslide criterion[J]. Chinese Journal of Rock Mechanics and Engineering, 24(17):3146-3153. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb200517023 Shuzui H. 2001. Process of slip-surface development and formation of slip-surface clay in landslides in Tertiary volcanic rocks, Japan[J]. Engineering Geology, 61(4):199-219. doi: 10.1016/S0013-7952(01)00025-4 Sun J. 1999. Rheological properties of geomaterials and its application to engineering[M]. Beijing:China Architecture and Building Press. Sun J. 2007. Rock rheological mechanics and its advance in engineering applications[J]. Chinese Journal of Rock Mechanics and Engineering, 26(6):1081-1106. https://www.researchgate.net/publication/281563287_Rock_rheological_mechanics_and_its_advance_in_engineering_applications Tan T K, Li K R. 1981. Relaxation and creep properties of thin interbedded clayey seams and their fundamental role in the stability of dams[C]//Proceeding of ISRM International Symposium. Tokyo, Japan: ISRM: 369-374. https://www.onepetro.org/conference-paper/ISRM-IS-1981-059 Voight B, Faust C. 1982. Frictional heat and strength loss in same rapid slides[J]. Géotechnique, 32(1):43-54. doi: 10.1680/geot.1982.32.1.43 Wang B J, Wang T, Sun J Z, et al. 2017. Shearing characteristic of sliding zone soil from ring shear tests for large scale mudstone landslides in Huangshui river basin[J]. Journal of Engineering Geology, 25(1):123-131. http://www.en.cnki.com.cn/Article_en/CJFDTotal-GCDZ201701017.htm Wang H J, Liu D A, Huang Z Q, et al. 2017. Mechanical properties and brittleness evaluation of layered shale rock[J]. Journal of Engineering Geology, 25(6):1414-1423. http://d.old.wanfangdata.com.cn/Periodical/gcdzxb201706004 Wang S J. 1990. Engineering geomechanics of rock mass in dam foundations[M]. Beijing:Science Press. Xu D P, Feng X T, Cui Y J, et al. 2012. On failure mode and shear behavior of rock mass with Interlayer staggered zone[J]. Rock and Soil Mechanics, 33(1):129-136. http://en.cnki.com.cn/Article_en/CJFDTotal-YTLX201201021.htm Xu Q, Fan X M, Huang R Q, et al. 2010. A catastrophic rockslide-debris flow in Wulong, Chongqing, China in 2009:background, characterization, and causes[J]. Landslides, 7(1):75-81. doi: 10.1007/s10346-009-0179-y Xu R C, Zhou J J. 2010. Red stratum and dam[M]. Beijing:China University of Georsciences Press. Yin Y P. 2004. Major geologic harzards and the prevention on relocation sites of the Three Gorges Reservoir, the Yangtze River[M]. Beijing:Geological Publishing House. Yin Y P. 2010. Mechanism of apparent dip slide of inclined bedding rockslide-a case study of Jiweishan rockslide in Wulong, Chongqing[J]. Chinese Journal of Rock Mechanics and Engineering, 19(2):217-226. http://d.wanfangdata.com.cn/Periodical/yslxygcxb201002001 冯振, 殷跃平, 李滨, 等. 2012.重庆武隆鸡尾山滑坡视向滑动机制分析[J].岩土力学, 33(9):2704-2712. http://d.old.wanfangdata.com.cn/Periodical/ytlx201209023 高杨, 李滨, 王国章. 2016.鸡尾山高速远程滑坡运动特征及数值模拟分析[J].工程地质学报, 24(3):425-434. http://www.gcdz.org/CN/abstract/abstract11989.shtml 兰恒星, 陈俊辉, 伍宇明. 2018.三轴压缩试验前后含气页岩微纳尺度裂隙空间分布特征研究[J].工程地质学报, 26(1):24-35. http://www.gcdz.org/CN/abstract/abstract12630.shtml 兰志勇, 赵建军, 翟崇, 等. 2014.软弱基座型斜坡变形破坏机制模拟研究[J].工程地质学报, 22(3):421-427. http://www.gcdz.org/CN/abstract/abstract11435.shtml 李守定, 李晓, 张年学, 等. 2006.三峡库区宝塔滑坡泥化夹层泥化过程的水岩作用[J].岩土力学, 27(10):1841-1846. doi: 10.3969/j.issn.1000-7598.2006.10.041 李晓, 李守定, 陈剑, 等. 2008.地质灾害形成的内外动力耦合作用机制[J].岩石力学与工程学报, 27(9):1792-1806. doi: 10.3321/j.issn:1000-6915.2008.09.006 廖秋林, 李晓, 李守定, 等. 2005.三峡库区千将坪滑坡的发生、地质地貌特征、成因及滑坡判据研究[J].岩石力学与工程学报, 24(17):3146-3153. doi: 10.3321/j.issn:1000-6915.2005.17.023 孙钧. 1999.岩土材料流变及其工程应用[M].北京:中国建筑工业出版社. 孙钧. 2007.岩石流变力学及其工程应用研究的若干进展[J].岩石力学与工程学报, 26(6):1081-1106. doi: 10.3321/j.issn:1000-6915.2007.06.001 王玢佳, 王涛, 孙进忠, 等. 2017.基于环剪试验的湟水河流域大型泥岩滑坡滑带剪切特征初探[J].工程地质学报, 25(1):123-131. http://www.gcdz.org/CN/abstract/abstract12332.shtml 王洪建, 刘大安, 黄志全, 等. 2017.层状页岩岩石力学特性及其脆性评价[J].工程地质学报, 25(6):1414-1423. http://www.gcdz.org/CN/abstract/abstract12601.shtml 王思敬. 1990.坝基岩体工程地质力学分析[M].北京:科学出版社. 徐鼎平, 冯夏庭, 崔玉军, 等. 2012.含层间错动带岩体的破坏模式及其剪切特性研究方法探讨[J].岩土力学, 33(1):129-136. doi: 10.3969/j.issn.1000-7598.2012.01.021 徐瑞春, 周建军. 2010.红层与大坝[M].北京:中国地质大学出版社. 殷跃平. 2004.长江三峡库区移民迁建新址重大地质灾害及防治研究[M].北京:地质出版社. 殷跃平. 2010.斜倾厚层山体滑坡视向滑动机制研究——以重庆武隆鸡尾山滑坡为例[J].岩石力学与工程学报, 19 (2):217-226. http://d.wanfangdata.com.cn/Periodical/yslxygcxb201002001 -
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