Triggering factor analysis of deposit slope under rainfall infiltration based on laboratory experiments
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摘要:
堆积体边坡稳定性判别和分析是地质灾害防治重点,分别以密实细颗粒边坡和松散碎石体边坡为例,开展了降雨入渗作用下坡体失稳室内模型试验,系统分析了密实度、物质组成、坡度以及植被覆盖度对边坡稳定性和降雨阈值的影响。结果表明,降雨入渗作用下,物质组成较均匀、密实度高的细颗粒边坡稳定性较好,坡体失稳降雨阈值高,致灾性较低;物质组成不均、松散碎石体边坡相较于密实细颗粒边坡更容易失稳破坏,含石量对坡体稳定性的影响要大于坡体坡度;坡体失稳临界降雨量随植被覆盖度的增大先升高后降低,即当降雨入渗致使边坡土体过饱和时,较高的植被覆盖度反而会由于植被根系的强发育,触发坡体和植被整体破坏,并加大坡体致灾能力。研究成果可以为堆积体边坡失稳机理研究及其稳定性评价提供理论依据。
Abstract:The identification and analysis of the deposit slope stability is the focus of geological disaster prevention and control. Taking dense-fine grained slopes and loose gravel slopes as examples, a series of flume tests under rainfall infiltration were carried out. The effects of density, material composition, slope angle and vegetation coverage on slope stability and rainfall threshold were systematically analyzed. The results show that under rainfall infiltration, the dense-fine grained slope with uniform material composition and high density was more stable, resulting in a higher rainfall threshold and a lower catastrophability. The slope with non-uniformmaterial composition and loose gravel was more likely to fail than the slope with dense fine particles. The influence of the stone content on the stability of the slope is greater than that of the slope gradient. The critical rainfall of landslides increases first and then decreases with an increasing vegetation coverage; that is, when rainfall infiltration causes the slope soil to be supersaturated, the higher vegetation coverage will trigger the whole deformation of slope and vegetation due to the strong development of vegetation roots, which increases the catastrophability of the slope.The research results can provide a theoretical basis for the instability mechanism and stability evaluation of deposit slopes.
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表 1 松散堆积体室内试验设计
Table 1. Experimental design of the loose accumulation slope
序号 坡度/(°) 碎石比/% 1 50 50 2 60 20 3 40 0 4 40 50 5 40 20 6 50 0 7 60 50 8 50 20 9 60 0 -
[1] 魏玉杰, 夏金文, 蔡崇法. 松散堆积体侵蚀特性研究概述[C]//佚名. 海峡两岸红壤区水土保持学术研讨会. [S. l.]: [s. n.], 2015: 283-288.Wei Y J, Xia J W, Cai C F. Overview of research on erosion characteristics of loose deposits[C]//Anon. Symposium on Soil and Water Conservation in Red Soil Regions Across the Straits. [S. l.]: [s. n.], 2015: 283-288(in Chinese with English abstract). [2] 杨登芳, 胡新丽, 徐楚, 等. 基于物理模型试验的多层滑带滑坡变形演化特征[J]. 地质科技通报, 2022, 41(2): 300-308. doi: 10.19509/j.cnki.dzkq.2021.0069Yang D F, Hu X L, Xu C, et al. Deformation and evolution characteristics of landslides with multiple sliding zones based on physical model test[J]. Bulletin of Geological Science and Technology, 2022, 41(2): 300-308(in Chinese with English abstract). doi: 10.19509/j.cnki.dzkq.2021.0069 [3] 董辉, 李智飞, 蒋秀姿, 等. 强降雨作用下碎石土斜坡室内模型试验研究[J]. 安全与环境学报, 2016, 16(4): 236-241. https://www.cnki.com.cn/Article/CJFDTOTAL-AQHJ201604050.htmDong H, Li Z F, Jiang X Z, et al. Model test research on the gravel-cluttered soil slope under the heavy artificial rainfall condition[J]. Journal of Safety and Environment, 2016, 16(4): 236-241(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-AQHJ201604050.htm [4] 石振明, 赵思奕, 苏越. 降雨作用下堆积层滑坡的模型试验研究[J]. 水文地质工程地质, 2016, 43(4): 135-141. https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG201604024.htmShi Z M, Zhao S Y, Su Y. An experimental study of the deposit slope failure caused by rainfall[J]. Hydrogeological & Engineering Geology, 2016, 43(4): 135-141(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG201604024.htm [5] 李继兴, 严松, 杨春健, 等. 泥质砂岩残积土边坡降雨冲刷特性[J]. 地质科技通报, 2022, 41(2): 26-33. doi: 10.19509/j.cnki.dzkq.2022.0051Li J X, Yan S, Yang C J, et al. Rainfall erosion characteristics of argillaceous sandstone residual soil slope[J]. Bulletin of Geological Science and Technology, 2022, 41(2): 26-33(in Chinese with English abstract). doi: 10.19509/j.cnki.dzkq.2022.0051 [6] 梁润娥. 降雨入渗堆积层滑坡的稳定性分析与评价[J]. 地质灾害与环境保护, 2020, 31(2): 14-18. https://www.cnki.com.cn/Article/CJFDTOTAL-DZHB202002003.htmLang R E. Analysis and evaluation of rainfall infiltration accumulation layer landslide[J]. Journal of Geological Hazards and Environment Preservation, 2020, 31(2): 14-18(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZHB202002003.htm [7] 谭明健, 周春梅, 孙东, 等. 软硬互层顺层岩质边坡破坏试验[J]. 地质科技通报, 2022, 41(2): 274-281. doi: 10.19509/j.cnki.dzkq.2021.0096Tan M J, Zhou C M, Sun D, et al. Failure experiment of soft-hard interlayer bedding rock slope[J]. Bulletin of Geological Science and Technology, 2022, 41(2): 274-281(in Chinese with English abstract). doi: 10.19509/j.cnki.dzkq.2021.0096 [8] 贺可强. 大型堆积层滑坡的多层滑移规律分析[J]. 金属矿山, 1998, 26(7): 15-18. https://www.cnki.com.cn/Article/CJFDTOTAL-JSKS807.004.htmHe K Q. An analysis on the multilayered slide law of the large scale accumulative landslides[J]. Metal Mine, 1998, 26(7): 15-18(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-JSKS807.004.htm [9] Lee K, Suk J, Kim H, et al. Modeling of rainfall-induced landslides using a full-scale flume test[J]. Landslides, 2021, 18: 1153-1162. [10] Cogan J, Gratchev I. A study on the effect of rainfall and slope characteristics on landslide initiation by means of flume tests[J]. Landslides, 2019, 16: 2369-2379. http://www.xueshufan.com/publication/2969313895 [11] Macciotta R, Hendry M, Martin C D. Developing an early warning system for a very slow landslide based on displacement monitoring[J]. Natural Hazards, 2015, 81(2): 887-907. http://www.onacademic.com/detail/journal_1000038583245910_440a.html [12] Iverson R M, Reid M E, Iverson N R, et al. Acute sensitivity of landslide rates to initial soil porosity[J]. Science, 2000, 290: 513-516. doi: 10.1126/science.290.5491.513 [13] Huang C C, Ju Y J, Hu L K, et al. Internal soil moisture and piezometric responses to rainfall-induced shallow slope failures[J]. J. Hydrol., 2009, 370: 39-51. http://www.sciencedirect.com/science/article/pii/S0022169409001401/ [14] Cui Y, Guo C, Zhou X. Experimental study on the moving characteristics of fine grains in wide grading unconsolidated soil under heavy rainfall[J]. J. Mt. Sci., 2017, 14(3): 417-431. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=sdkxxb-e201703001 [15] Zhang S, Xu Q, Zhang Q. Failure characteristics of gently inclined shallow landslides in Nanjiang, southwest of China[J]. Eng. Geol., 2017, 217: 1-11. http://www.sciencedirect.com/science?_ob=ShoppingCartURL&_method=add&_eid=1-s2.0-S0013795216307062&originContentFamily=serial&_origin=article&_ts=1490492112&md5=c68f08a343871aaa0b9caf9b19e0fbb0 [16] Wang G, Sassa K. Pore-pressure generation and movement of rainfall-induced landslides: Effects of grain size and fine-particle content[J]. Eng. Geol., 2003, 69: 109-125. http://cyber.sci-hub.se/MTAuMTAxNi9zMDAxMy03OTUyKDAyKTAwMjY4LTU=/wang2003.pdf?download=true [17] 李焕强, 孙红月, 孙新民, 等. 降雨入渗对边坡性状影响的模型实验研究[J]. 岩土工程学报, 2009, 31(3): 589-594. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200904020.htmLi H Q, Sun H Y, Sun X M, et al. Influence of rainfall infiltration on slopes by physical model test[J]. Chinese Journal of Geotechnical Engineering, 2009, 31(3): 589-594(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200904020.htm [18] 林鸿州, 于玉贞, 李广信, 等. 降雨特性对土质边坡失稳的影响[J]. 岩石力学与工程学报, 2009, 28(1): 198-204. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200901030.htmLin H Z, Yu Y Z, Li G X, et al. Influence of rainfall characteristics on soil slope failure[J]. Chinese Journal of Rock Mechanics and Engineering, 2009, 28(1): 198-204(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200901030.htm [19] 陈天健, 蔡和伦, 黄彦荣, 等. 人工降雨模型试验研究降雨入渗对滑坡类型之影响[J]. 水土保持研究, 2012, 19(1): 254-257. https://www.cnki.com.cn/Article/CJFDTOTAL-STBY201201055.htmChen T J, Cai H L, Huang Y R, et al. Slope failure mode related to soil infiltration-laboratory rainfall model test[J]. Research of Soil and Water Conservation, 2012, 19(1): 254-257(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-STBY201201055.htm [20] Zhou Z, Wang H G, Fu H L. Influences of rainfall infiltration on stability of accumulation slope by in-situ monitoring test[J]. Journal of Central South University of Technology, 2009, 16(2): 297-302. http://www.zndxzk.com.cn/down/paperDown.aspx?id=59475 [21] 许建聪, 尚岳全. 碎石土滑坡的因素敏感性计算分析[J]. 岩土力学, 2007, 28(10): 2046-2051. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX200710006.htmXu J C, Shang Y Q. Sensitivity analysis of influencing factors of debris landslide[J]. Rock and Soil Mechanics, 2007, 28(10): 2046-2051(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX200710006.htm