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CHARACTERISTICS OF SEISMIC WAVE VELOCITY OF POTENTIAL SLOPE FAILURE IN LISHI LOESS STRATA
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摘要: 崩塌是黄土高原地区最常见、致灾最为严重的地质灾害之一。本文通过野外钻探，采用原位地震波测试的方法，详细分析了离石黄土崩塌隐患体内部的波速结构特征。结果发现，在竖直方向上，地震波速整体随深度增加而增大；水平方向上，地震波速自边坡坡面向坡体内部逐渐增大。结合数值模拟，发现崩塌隐患体由于受到卸荷回弹作用的影响，产生了指向坡外的形变。形变增量的大小与距离边坡坡面的远近有关，距离坡面越近形变增量越大，致使对应土体的密实度减小。密实度的减小是隐患体内部波速存在差异的重要原因。研究表明，利用地震波速的变化规律可以宏观反映崩塌隐患体内部结构特征，进而指导黄土崩塌地质灾害的防治研究。Abstract: Collapse is one of the most common and serious geological disasters in the Loess Plateau of China. In this paper, the seismic wave velocity characteristics of the potential slope failure internal structure of Lishi loess are analysed in detail using the in-situ seismic wave testing through field drilling test. The results show that the seismic wave velocity in the vertical direction increases with the depth, while the seismic wave velocity in the horizontal direction gradually increases from slope surface to interior of the slope. Numerical simulation results indicate that the potential slope failure generates outward deformation due to the unloading rebound. The deformation increment is related to distance to the slope surface, the closer the distance, the greater the deformation increment. The decrease of density is an important reason for the difference of wave velocity in the potential failure. The study shows that the variation pattern of seismic wave velocity can reflect the internal structure characteristics of the potential slope failure, and thus can be a method in research on prevention and control of loess collapses.
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Key words:
- Lishi loess /
- Potential slope failure /
- Seismic wave velocity /
- Unloading rebound /
- Numerical simulation
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图 1 试验场地概况
a. 试验场地周边地形地貌；b. 试验场地地质剖面
Figure 1. Overview of the test site:(a)Landform; and (b)Geological profile of the test site
图 2 地震波速测试布置方案
a. 平面布置图；b. 三维布置图
Figure 2. Test layout for seismic wave velocity measurement:(a) The plane layout; and (b)3D view
图 4 不同地形边界关键检波点的时距曲线(a)和分层波速(b)
Figure 4. Difference in time-distance curves(a) and wave velocity in different directions(b)
图 5 5不同深度地层波速的各向异性：
(a). 1 m；(b). 10 m and (c). 20 m a.1 m；b.10 m；c.20 m
Figure 5. Anisotropy of wave velocity at different depths:
图 7 坡顶浅表土体天然密度与边坡距的关系
Figure 7. Relationship between natural density of shallow soil and the distance to slope surface
图 8 黄土崩塌隐患体崩塌卸荷变形分析
a. 水平位移增量等值线；b. 水平位移增量迹线
Figure 8. Deformation of loess slope due to horizontal unloading: (a)Contour map of horizontal displacement increment and(b)Vector graph of horizontal displacement increment
图 9 3个不同深度(1 m、10 m、20 m)剖面线位置处水平位移增量的变化趋势
Figure 9. Variation of horizontal displacement increment along profiles at different depths
表 1 模型边坡基础物理参数
Table 1. Physical parameters of Lishi loess in the test site
类型 弹性模量E/N·m-2 黏聚力c/kPa 内摩擦角φ/(°) 泊松比ν 重度γ/kN·m-3 天然重度 饱和重度 莫尔-库仑模型 2×104 8 29 0.33 17 19 
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Cai Y Q, Li B Q, Xu C J. 2010. Characteristics of retaining structures of deep foundation pits under different excavation depths[J]. Chinese Journal of Geotechnical Engineering, 32 (S1): 28-31. Chen Y M, Wang L M, Liu H M. 2003. Prediction method of seismic subsidence of loess ground with shear wave velocity[J]. Chinese Journal of Rock Mechanics and Engineering, 22 (S2): 2834-2839. Feng L C, Zheng Y W. 1982. Collapsible loess in China[M]. Beijing: China Railway Publishing House. Fu X J, Lin Z Z. 2010. Elastoplastic finite element numerical calculation and analysis of ultra-deep foundation pit excavation based on PLAXIS[J]. China Water Transport, 10 (4): 190-192. doi: 10.3969/j.issn.1006-7973-C.2010.04.097 Hou Y L. 2007. Research on correlation between shear wave volecity and engineering properties of soil in Xi'an area loess[D]. Xi'an: Chang'an University. Jiang H B, Lü Y Q, Zhu J. 2010. Deformation analysis of loess high slope in Shuiliandong coal mine industrial site[J]. Coal Engineering, (11): 42-45. doi: 10.3969/j.issn.1671-0959.2010.11.018 Jin M. 2006. Application of vertical and horizontal wave velocities in determining collapsibility of loess[J]. West China Exploration Engineering, (1): 20-21. Li Y R, Shi W H, Aydin A, et al. 2020. Loess genesis and worldwide distribution[J]. Earth-Science Reviews, 201: 102947. doi: 10.1016/j.earscirev.2019.102947 Liu C Z. 2019. Analysis methods on the risk identification of landslide disasters[J]. Journal of Engineering Geology, 27 (1): 88-97. Liu H J, Zhou T H. 2001. Study on the collapsibility of Q2 loess from several engineering practices[R]. Lanzhou: China Engineering Construction Standardization Association. Liu X Y. 2019. Failure modes and early identiffcation of typical loess collapse in Shanxi[J]. Journal of Yangtze River Scientific Research Institute, 36 (11): 69-75. doi: 10.11988/ckyyb.20181280 Liu X, Wang L M, Bai Y M. 2004. Experimental study on loess reinforced cohesion by elastic wave velocity[J]. Northwestern Seismological Journal, 26 (3): 218-222. Ni J, Li S S, Han Y Q, et al. 2019. Experimental study on creep behavior of saturated soft clays under loading and unloading conditions[J]. Journal of Engineering Geology, 27 (6): 1262-1269. Qu Y X, Zhang Y S, Chen Q L. 2001. Preliminary study on loess slumping in the area between northern Shaanxi and western Shanxi-Taking the pipeline for transporting GAS from west to east in China[J]. Journal of Engineering Geology, 9 (3): 233-240. doi: 10.3969/j.issn.1004-9665.2001.03.002 Wang G L, Zhang M S, Su T M, et al. 2011. Collapse failure modes and dem numerical simulation for loess slopes[J]. Journal of Engineering Geology, 19 (4): 541-549. doi: 10.3969/j.issn.1004-9665.2011.04.015 Wang L M, Yuan Z X, Wang J, et al. 2000. Laboratory study of effect of dry density on seismic settlement of compacted loess[J]. Earthquake Engineering and Engineering Vibration, 20 (1): 75-80. Wang P, Wang L M, Wang Q, et al. 2012. Study on critical shear wave velocity of saturated loess foundation soil liquefaction under different seismic magnitudes action[J]. Advanced Materials Research, 594/597 : 1720-1726. doi: 10.4028/www.scientific.net/AMR.594-597.1720 Wang Q. 2011. Study on loess liquefaction evaluation based on physical indexes and depth limit[D]. Lanzhou: Lanzhou Institute of Seismology, China Earthquake Administration. Wang Z H. 2007. Testing study on relationship among P-Wave Velocity and Physico-Mechanical in Xiashu loess[D]. Nanjing: Hohai University. Ye W J, Wang P, Yang G S, et al. 2013. Formation factors of loess collapse and method for determining its influence range[J]. Journal of Engineering Geology, 21 (6): 920-925. doi: 10.3969/j.issn.1004-9665.2013.06.021 Ye W J, Yang G S, Chang Z H, et al. 2011. Characteristics of development state of spalling hazard in loess slope and its evaluation method[J]. Journal of Engineering Geology, 19 (1): 37-42. Yuan S F. 2007. Discussion on determining the lithology of loess strata by using the conclusion of wave velocity measurement[J]. Geological Hazards and Environmental Protection, 126-129. Yuan W F. 1998. Application and research of wave velocity measurement in engineering[J]. Inland Earthquake, 12 (1): 50-57. 蔡袁强, 李碧青, 徐长节. 2010. 挖深不同情况下基坑支护结构性状研究[J]. 岩土工程学报, 32 (S1): 28-31. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2010S1007.htm 陈永明, 王兰民, 刘红玫. 2003. 剪切波速预测黄土场地震陷量的方法[J]. 岩石力学与工程学报, 22(增2): 2834-2839. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2003S2061.htm 冯连昌, 郑晏武. 1982. 中国湿陷性黄土[M]. 北京: 中国铁道出版社. 付先进, 林作忠. 2010. 基于PLAXIS的超深基坑开挖弹塑性有限元数值计算与分析[J]. 中国水运, 10 (4): 190-192. https://www.cnki.com.cn/Article/CJFDTOTAL-ZSUX201004102.htm 侯云亮. 2007. 西安地区黄土地基剪切波速与工程特性相关性的研究[D]. 西安: 长安大学. 姜海波, 吕远强, 祝建. 2010. 水帘洞煤矿工业场地黄土高边坡变形分析[J]. 煤炭工程, (11): 42-45. https://www.cnki.com.cn/Article/CJFDTOTAL-MKSJ201011018.htm 金敏. 2006. 纵横波速在判定黄土湿陷性方面的应用[J]. 西部探矿工程, (1): 20-21. https://www.cnki.com.cn/Article/CJFDTOTAL-XBTK200601009.htm 刘传正. 2019. 崩塌滑坡灾害风险识别方法初步研究[J]. 工程地质学报, 27 (1): 88-97. doi: 10.13544/j.cnki.jeg.2019-009 刘旭, 王兰民, 白耀明. 2004. 弹性波速反映黄土加固凝聚力变化的试验研究[J]. 西北地震学报, 26 (3): 218-222. https://www.cnki.com.cn/Article/CJFDTOTAL-ZBDZ200403018.htm 刘厚健, 周天红. 2001. 从多个工程实践看Q2黄土的湿陷性[R]. 兰州: 中国工程建设标准化协会. 刘向御. 2019. 山西典型黄土崩塌破坏模式及其早期辨识[J]. 长江科学院院报, 36 (11): 69-75. https://www.cnki.com.cn/Article/CJFDTOTAL-CJKB201911017.htm 倪静, 李杉杉, 韩玉琪, 等. 2019. 加卸荷条件下饱和软黏土蠕变特性试验研究[J]. 工程地质学报, 27 (6): 1262-1269. doi: 10.13544/j.cnki.jeg.2017-625 曲永新, 张永双, 陈情来. 2001. 陕北晋西黄土滑塌灾害的初步研究——以西气东输工程为例[J]. 工程地质学报, 9 (3): 233-240. http://www.gcdz.org/article/id/9375 王谦. 2011. 饱和黄土液化势的物性指标评价和深度下限研究[D]. 兰州: 中国地震局兰州地震研究所. 王根龙, 张茂省, 苏天明, 等. 2011. 黄土崩塌破坏模式及离散元数值模拟分析[J]. 工程地质学报, 19 (4): 541-549. http://www.gcdz.org/article/id/10052 王兰民, 袁中夏, 王峻, 等. 2000. 干密度对击实黄土震陷性影响的试验研究[J]. 地震工程与工程振动, 20 (1): 75-80. https://www.cnki.com.cn/Article/CJFDTOTAL-DGGC200001011.htm 王峥辉. 2007. 下蜀黄土超声波波速与物理力学性质试验研究[D]. 南京: 河海大学. 叶万军, 王鹏, 杨更社, 等. 2013. 黄土崩塌的形成因素及其影响范围的确定方法[J]. 工程地质学报, 21 (6): 920-925. http://www.gcdz.org/article/id/11366 叶万军, 杨更社, 常中华, 等. 2011. 黄土边坡剥落病害的发育特征及其发育程度评价[J]. 工程地质学报, 19 (1): 37-42. http://www.gcdz.org/article/id/8788 袁素凤. 2007. 运用波速测定结论确定黄土地层岩性探讨[J]. 地质灾害与环境保护: 126-129. 袁文福. 1998. 波速测试在工程中的应用与研究[J]. 内陆地震, 12 (1): 50-57. https://www.cnki.com.cn/Article/CJFDTOTAL-LLDZ199801007.htm -
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