Disaster Characteristics and Destructive Mechanism of Typical Loess Landslide Cases Triggered by Human Engineering Activities
-
摘要: 为了揭示人类工程活动诱发的黄土滑坡成灾机理,基于典型工程活动触发黄土滑坡案例分析,采用野外调查、物理模型试验和应力路径试验等方法,分析了堆载触发黄土滑坡剪切带形成过程、卸载触发黄土滑坡演化模式和灌溉诱发黄土滑坡的成灾过程。研究结果表明:堆载和卸载触发的黄土滑坡,垂直节理易演化成裂缝带,剪应力作用下剪切蠕变带逐渐由坡脚向坡体内部扩展,直至发展成贯通的剪切带,坡体整体变形破坏,堆载触发黄土滑坡具有典型浅层、深层双滑带特征;灌溉诱发黄土滑坡主要发育在黄土塬边,长期农田灌溉导致地下水抬升,坡体内形成饱和带,重力荷载作用下发生蠕动剪切破坏,滑坡开始启动,大规模的快速覆盖加载导致坡体前部浅层黄土液化,最终触发黄土泥流远程滑坡。Abstract: In order to reveal the mechanism of loess landslide hazards induced by human engineering activities, typical loess landslide cases were studied using field investigations, physical model tests, and stress path tests. Analyses were made for the formation of shear zones triggered by heap loading, the evolution patterns of loess landslides triggered by unloading, and the development process of loess landslides induced by irrigation. The results show that in loess landslides triggered by heap loading and unloading, vertical joints and cracks easily evolve into a fracture belt. Under the action of shear stresses, shear creep zones expand from the toe to the internal of a slope gradually and develop into shear zones that penetrate the slope, which leads to the overall deformation and failure of slopes. Physical model tests reveal that the loess landslides triggered by heap loading have a typical feature of two sliding zones in shallow and deep layers. The loess landslides triggered by irrigation mainly develop in the loess tableland edge. The long-term irrigation will uplift the groundwater and cause the formation of a saturated zone in the slope body. The creep shear failure then occurs to the slope under the gravity load, resulting in the start of a landslide. In addition, the large-scale fast loading process will cause the liquefaction of the shallow loess in the front section of the slope body, and eventually triggers long-range loess mud flow landslides.
-
Key words:
- engineering activities /
- loess landslide /
- heap loading /
- unloading /
- irrigation /
- disaster mechanism
-
雷祥义. 黄土高原地质灾害与人类活动[M]. 北京:地质出版社,2001: 30-35. WANG J J, LIANG Y, ZHANG H P, et al. A loess landslide induced by excavation and rainfall[J]. Landslides, 2014, 11(1): 141-152. DERBYSHIRE E, MENG X M, DIJKSTRA T A. Landslides in the thick loess terrain of north-west China[M]. London: John Wiley Sons Ltd., 2000: 4-39. LI T L, WANG C Y, LI P. Loess deposit and loess landslides on the Chinese loess plateau[C]//Progress of Geo-Disaster Mitigation Technology in Asia, Environmental Science and Engineering. : Springer-Verlag Berlin Heidelberg, 2013: 235-261. ZHUANG J Q, PENG J B. A coupled slope cutting-a prolonged rainfall-induced loess landslide: a 17 October 2011 case study[J]. Bulletin of Engineering Geology and the Environment, 2014, 73(4): 997-1011. DERBYSHIRE E, DIJKSTRA T A, SMALLEY I J, et al. Failure mechanisms in loess and the effects of moisture content changes on remolded strength[J]. Quaternary International, 1994, 24: 5-15. DIJKSTRA T A, ROGERS C D F, VAN ASCH T W J. Cut slope and terrace edge failures in Malan loess, Lanzhou, PR China[C]// Proceedings of the XI ECSMFE Conference. Copenhagen: , 1995: 61-67. MENG X M. Loess and loess instability in north China[D]. London: University of London, 1998. 李同录,龙建辉,李新生. 黄土滑坡发育类型及其空间预测方法[J]. 工程地质学报,2007,15(4): 500-506. LI Tonglu, LONG Jianhui, LI Xinsheng. Types of loess landslides and methods for their movement forecast[J]. Journal of Engineering Geology, 2007, 15(4): 500-506. WANG L M, LING H M. Laboratory study on the mechanism and behaviors of saturated loess liquefaction[J]. Chinese Journal of Geotechnical Engineering, 2000, 22(1): 89-94. WANG Z R, WU W J, ZHOU Z Q. Landslide induced by over-irrigation in loess platform areas in Gansu Province[J]. The Chinese Journal of Geological Hazard and Control, 2004, 15(3): 43-46. XU L, DAI F C, GONG Q M, et al. Irrigation-induced loess flow failure in Heifangtai Platform, north-west China. Environ[J]. Earth Sci., 2012, 66: 1707-1713. XU L, DAI F, TU X, et al. Landslides in a loess platform, north-west China[J]. Landslides, 2014, 11(6): 993-1005. ZHANG D, WANG G, LUO C, et al. A rapid loess flowslide triggered by irrigation in China[J]. Landslides, 2009, 6(1): 55-60. ZHANG M S, LIU J. Controlling factors of loess landslides in western China[J]. Environ. Earth Sci., 2010, 59: 1671-1680. ZHANG F Y, WANG G H, KAMAI T, et al. Undrained shear behavior of saturated loess at different concentrations of sodium chlorate solution[J]. Engineering Geology, 2013, 155(1): 69-79. 谢定义. 试论我国黄土力学研究中的若干新趋向[J]. 岩土工程学报,2001,23(1): 3-13. XIE Dingyi. Exploration of some new tendencies in research of loess soil mechanics[J]. Chinese Journal of Geotechnical, 2001, 23(1): 3-3. 邵生俊,周飞飞,龙吉勇. 原状黄土结构性及其定量化参数研究[J]. 岩土工程学报,2004,26(4): 531-536. SHAO Shengjun, ZHOU Feifei, LONG Jiyong. Structural properties of loess and its quantitative parameter[J]. Chinese Journal of Geotechnical, 2004, 26(4): 531-536. 徐张建,林在贯,张茂省. 中国黄土与黄土滑坡[J]. 岩石力学与工程学报,2007,26(7): 1297-1312. XU Zaijian, LIN Zaiguan, ZHAO Maosheng, Loess in China and loess landslides[J]. Chinese Journal of Rock Mechanics and Engineering, 2007, 26(7): 1297-1312. 周翠英. 土体微观结构研究与土力学的发展方向-若干进展与思考[J]. 地球科学-中国地质大学学报,2000,25(2): 215-220. ZHOU Cuiying. Research into soil mass microstructure and some progress on soil mechanics[J]. Earth Science- Journal of China University of Geosciences, 2000, 25(2): 215-220. 王念秦,张倬元. 黄土滑坡灾害研究[M]. 兰州:兰州大学出版社,2005: 36-99. LIN Z G, LIANG W M. Engineering properties and zoning of loess and loess-like soils in China[J]. Canadian Geotechnical Journal, 1982, 19(1): 76-91. GAO G R. Formation and development of the structure of collapsing loess in China[J]. Engineering Geology, 1988, 25: 235-245. ZHANG Dexuan, WANG Gonghui, LUO Chunyong, et al. A rapid loess flowslide triggered by irrigation in China[J]. Landslides, 2009, 6(1): 55-60. 王兰民,刘红玫,李兰,等. 饱和黄土液化机理与特性的试验研究[J]. 岩土工程学报,2000,22(1): 89-94. WANG Lanmin, LIU Hongmei, LI Lan, et al. Laboratory study on the mechanism and behaviorsof saturated loess liquefaction[J]. Chinese Journal of Geotechnical Engineering, 2000, 22(1): 89-94. 李广信,武世锋. 土的卸载体缩现象及其变形机理探讨[J]. 岩土工程学报,2002(1): 47 -50. LI Guangxin, WU Shifeng, Experimental research on volume-contraction of soil under unloadingand examination of its mechanism[J].Chinese Journal of Geotechnical Engineering, 2002(1): 47-50. HU R L, YEUNG M R, LEE C F, et al. Mechanical behavior and microstructural variation of loess under dynamic compaction[J]. Engineering Geology, 2001, 59: 203-217. 彭建兵,林鸿州,王启耀,等. 黄土地质灾害研究中的关键问题与创新思路[J].工程地质学报,2014,22(4): 684-691. PENG Jianbing, LIN Hongzhou, WANG Qiyao, et al. The critical issues and creative concepts in mitigation research of loess geological hazards[J]. Journal of Engineering Geology, 2014, 22(4): 684-691. LIU Y, HUANG QB. Test study for simulating soil deformation mechanism of loess slope under load condition[J]. Journal of Earth Sciences and Environment, 2007, 29(2): 183-187. 宋飞,李亚兰,陈志新. 考虑坡面稳定的黄土高切坡设计研究[J]. 水文地质工程地质,2008,2: 45-48. SONG Fei, LI Yalan, CHEN Zhixin, Design on high cutting loess slope considering slope surface stability[J]. Hydrogeology and Engineering Geology, 2008, 2: 45-48. AZAN J M, AZOR A, PREZ-PEA J V, et al . Late Quaternary large-scale rotational slides induced by river incision: The Arroyo de Gor area (Guadix basin, SE Spain)[J]. Geomorphology, 2005, 69: 152-168. HAO J M. Numerical calculation of rock slope stability induced by blasting cutting slope[J]. Mine Construction Technology, 2006, 24(6): 27-31. 中国航空研究院. 应力强度因子手册[M]. 北京:科学出版社,1981: 119-120. 沈珠江,邓刚. 黏土干湿循环中裂缝演变过程的数值模拟[J]. 岩土力学,2004,25(增刊2): 1-6. SHEN Zhujiang, DENG Gang, Numerical simulation of crack evolution in clay during drying and wetting cycle[J]. Rock and Soil Mechanics, 2004, 25(Sup.2): 1-6. 吴永,何思明,李新坡,等. 震后裂缝危岩体的失稳机理与诊断方法[J]. 四川大学学报:工程科学版, 2010,42(5): 185-190. WU Yong, HE Siming, LI Xinpo, et al. Failure mechanism and diagnosis method of dangerous crack rock after searthquake[J]. Journal of Sichuan University: Engineering Science Edition, 2010, 42(5): 185-190.
点击查看大图
计量
- 文章访问数: 750
- HTML全文浏览量: 90
- PDF下载量: 22
- 被引次数: 0