STUDY ON SLOPE STABILITY UNDER COUPLING LOADING CONDITION BY LIMIT ANALYSIS METHOD
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摘要: 边坡失稳产生的灾害不仅会给工农业生产带来巨大损失,也会对人民的生命财产安全造成巨大威胁。目前,滑坡灾害已与地震、火山并列成为全球3大地质灾害之一,其中由水库水位变化诱发的滑坡近来得到重视。因此,建立合理的边坡稳定性分析方法对预测以及防控滑坡灾害十分重要。实际中的边坡失稳过程往往在多种荷载因素的耦合作用下发生,但现有边坡极限分析等稳定性解析方法偏重于考虑单一荷载因素,难以合理考虑多类荷载耦合作用条件,缺乏对边坡稳定性依赖加载过程这一现象的合理解释。本文在极限分析原理的基础上,将水库区边坡所受荷载凝练为水位上升与坡顶加载的耦合作用。将水位荷载简化为水位线以下土体受到浮力以及黏聚力的减小,建立了一个土坡稳定性分析方法,编写了相应的数值计算程序,通过与离心模型试验结果进行对比验证了方法的有效性。该方法计算结果表明,边坡稳定性随坡顶荷载增加单调下降,而随水位上升表现出先降低后增加的非单调变化。因此,坡顶荷载与水位上升耦合加载过程中,边坡稳定性对于加载过程具有显著的依赖性。Abstract: Slope instability will not only bring huge losses to industrial and agricultural production, but also pose a great threat to the safety of people's lives. At present, landslides have become one of the three major geological disasters in the world, together with earthquakes and volcanoes. Landslides are caused by a variety of factors such as reservoir water level change. The reservoir water level change induced landslides are particularly concerned. Therefore, it is of great importance to establish a reasonable slope stability analysis method for predicting and preventing landslide hazards. The actual slope instability process often occurs under the coupling effect of various loading factors. However, previous analytical methods such as the limit analysis method focus on the influence of single factor on slope stability and are difficult to reasonably consider coupling application of various factors. Accordingly, they cannot capture the path dependence of the slope stability. In this paper, we establish a model of a soil slope under the combination of top loading and water level change on the basis of the limit analysis method. We assume that the soil below the water level is subject to buoyancy and reduction of cohesion. The effectiveness of the model is verified by the centrifuge test results. The model predictions reveal that the slope stability monotonically decreases with increasing top load, and non-monotonically changes with increasing water level. Therefore, the slope stability is significantly dependent on the coupled loading process.
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Key words:
- Slope /
- Stability /
- Limit analysis /
- Path dependency /
- Centrifuge model tests
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图 1 物体A绕物体B的刚体运动(陈惠发,1995)
Figure 1. Rigid body rotation of object A around B(Chen, 1995)
表 1 4种离心模型试验结果与本文方法预测结果
Table 1. Centrifugal model test results and predictions
荷载条件 方法预测 试验结果 误差/% 仅坡顶加载 294 kPa 320 kPa 8.84 仅水位加载 5.31 m 5.5 m 3.58 先蓄水,后加载 12.5 m,108.24 kPa 12.5 m,100 kPa 7.61 先加载,后蓄水 98.66 kPa,7.5m 100 kPa,7.5 m 1.36 -
Chen C H. 2012. Stability analysis of building slope under external loads[J]. Journal of Hunan City University(Natural Sciences), 21(1): 22-24. http://en.cnki.com.cn/Article_en/CJFDTotal-HNCG201201008.htm Chen H F. 1995. Limit analysis and soil plasticity[M]. Beijing: China Communications Press. Deng H F, Li J L. 2014. Research on the influence mechanism of water level fluctuation on the bank landslide deformation and stability[J]. Journal of Hydraulic Engineering, 45 (S2): 45-51. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=9291175 Griffiths D V, Lane P A. 1999. Slope stability analysis by finite elements[J]. Géotechnique, 49(3): 387-403. http://d.old.wanfangdata.com.cn/Periodical/cjkxyyb201901018 Huang L J. 2008. Research on effect of rock slope stability under load of building[J]. Journal of Hebei North University(Natural Sciences Edition), 24(6): 56-59. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hbbfxyxb-z200806018 Jia G W, Zhan L T, Chen Y M. 2009. Model test study of slope instability induced by rapid drawdown of water level[J]. Chinese Journal of Rock Mechanics and Engineering, 28(9): 1798-1803. http://d.old.wanfangdata.com.cn/Periodical/gckc201211005 Jiang Q Q, Liu L L, Jiao Y Y, et al. 2019. Strength properties and microstructure characteristics of slip zone soil subjected to wetting-drying cycles[J]. Rock and Soil Mechanics, 40 (3): 1005-1012, 1022. http://d.old.wanfangdata.com.cn/Periodical/ytlx201903021 Lane P A, Griffiths D V. 2000. Assessment of stability of slopes under drawdownconditions[J]. Journal of Geotechnical and Geoenviromental Engineering, 126(5): 443-450. https://www.researchgate.net/publication/239388886_Assessment_of_Stability_of_Slopes_under_Drawdown_Conditions Li R J, Yu Y Z, Deng L J. 2007. Discussion on stability analysis of unsaturated soil slope[J]. Rock and Soil Mechanics, 28(10): 2060-2064. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=HANS201910240208 Li S L, Xu Q, Tang M G, et al. 2017. Response patterns of old landslides with different slip-surface shapes triggered by fluctuation of reservoir water level[J]. Journal of Engineering Geology, 25(3): 841-852. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=gcdzxb201703032 Liu C H, Chen C X, Feng X T. 2005. Study on mechanism of slope instability due to reservoir water level rise[J]. Rock and Soil Mechanics, 26(5): 769-773. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytlx200505018 Luo X H, Li J Y. 2003. Analysis of reservoir impoundment influence on reservoir bank slide[J]. Design of Hydroelectric Power Station, 19 (3): 61-64, 69. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=sdzsj200303017 Mao C X. 2003. Seepage computation analysis & control[M]. Beijing: China Water & Power Press. Miao F S, Wu Y P, Xie Y H, et al. 2018. Centrifugal test on retrogressive landslide influenced by rising and falling reservoir water level[J]. Rock and Soil Mechanics, 39(2): 605-613. http://d.old.wanfangdata.com.cn/Periodical/ytlx201802025 Shi W M, Zheng Y R, Tang B M. 2003. Discussion on stability analysis method for landslides[J]. Rock and Soil Mechanics, 24 (4): 545-548, 552. http://cn.bing.com/academic/profile?id=24fd54f412150f19f2a06a6ca64cddb2&encoded=0&v=paper_preview&mkt=zh-cn Su Y H, Li S, Fang Y B, et al. 2019. Reliability evaluation of slope stability based on upper bound analysis[J]. Journal of Engineering Geology, 27(2): 451-458. http://d.old.wanfangdata.com.cn/Periodical/gcdzxb201902027 Tao Z G, Zhao J K, Zhang H J, et al. 2017. Research on stability influence law of gently inclined bedding slope under condition of peakload[J]. Coal Technology, 36(3): 64-67. http://en.cnki.com.cn/Article_en/CJFDTotal-MTJS201703024.htm Travis Q B, Houston S L, Marinho F A M, et al. 2010. Unsaturated infinite slope stability considering surface fluxconditions[J]. Journal of Geotechnical and Geoenvironmental Engineering, 136(7): 963-974. https://www.researchgate.net/publication/245294784_Unsaturated_Infinite_Slope_Stability_Considering_Surface_Flux_Conditions Wang G L, Wu F Q, Men Y M. 2006. Analysis of reliability index calculation on the basis of plasticity limit analysis and slice method of soil slope[J]. Journal of Engineering Geology, 14(6): 835-840. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=gcdzxb200606020 Wulandari S N, Li A J, Wahyudi H. 2019. Effects of pore water pressure on cohesive-frictional slope stability by limitanalysis[J]. IOP Conference Series: Earth and Environmental Science, 351(1): 012015. Xu W J, Wang L C, Hu R L. 2009. Fluid-solid coupling characteristics and stability analysis of soil-rock mixture slope in rising and drawdown of reservoir water levels[J]. Chinese Journal of Rock Mechanics and Engineering, 28(7): 1491-1498. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yslxygcxb200907024 Yang F, Xu Q, Fan X M, et al. 2019. Prediction of landslide displacement time series based on Support Vector Regression Machine with Artificial Bee Colony algorithm[J]. Journal of Engineering Geology, 27(4): 880-889. http://d.old.wanfangdata.com.cn/Periodical/gcdzxb201904022 Yang J H, Wang J M, Dong J Y, et al. 2011. Analysis of transient stability of deposits slope in process of reservoir impounding[J]. Rock and Soil Mechanics, 32 (S1): 464-470. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=8823179 Zhou J W, Chen M L, Li H B, et al. 2019. Formation and movement mechanisms of water-induced landslides and hazard prevention and mitigation technologies[J]. Journal of Engineering Geology, 27(5): 1131-1145. 陈朝辉. 2012.建筑边坡在外荷载作用下的稳定性分析[J].湖南城市学院学报(自然科学版), 21(1): 22-24. http://d.old.wanfangdata.com.cn/Periodical/huncjgdzkxxxb201201009 陈惠发. 1995.极限分析与土体塑性[M].北京:人民交通出版社. 邓华锋, 李建林. 2014.库水位变化对库岸边坡变形稳定的影响机理研究[J].水利学报, 45 (S2): 45-51. http://www.cnki.com.cn/Article/CJFDTotal-SLXB2014S2008.htm 黄丽娟. 2008.建筑荷载对岩质边坡稳定性影响研究[J].河北北方学院学报(自然科学版), 24(6): 56-59. http://d.old.wanfangdata.com.cn/Periodical/hbbfxyxb-z200806018 贾官伟, 詹良通, 陈云敏. 2009.水位骤降对边坡稳定性影响的模型试验研究[J].岩石力学与工程学报, 28(9): 1798-1803. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb200909009 江强强, 刘路路, 焦玉勇, 等. 2019.干湿循环下滑带土强度特性与微观结构试验研究[J].岩土力学, 40 (3): 1005-1012, 1022. http://d.old.wanfangdata.com.cn/Periodical/ytlx201903021 李荣建, 于玉贞, 邓丽军, 等. 2007.非饱和土边坡稳定分析方法探讨[J].岩土力学, 28(10): 2060-2064. http://d.old.wanfangdata.com.cn/Periodical/ytlx200710010 李松林, 许强, 汤明高, 等. 2017.库水位升降作用下不同滑面形态老滑坡响应规律[J].工程地质学报, 25(3): 841-852. doi: 10.13544/j.cnki.jeg.2017.03.032 刘才华, 陈从新, 冯夏庭. 2005.库水位上升诱发边坡失稳机理研究[J].岩土力学, 26(5): 769-773. http://d.old.wanfangdata.com.cn/Periodical/ytlx200505018 罗晓红, 李进元. 2003.水库蓄水对库岸滑坡影响分析[J].水电站设计, 19 (3): 61-64, 69. http://d.old.wanfangdata.com.cn/Periodical/sdzsj200303017 毛昶熙. 2003.渗流计算分析与控制[M].北京:中国水利水电出版社. 苗发盛, 吴益平, 谢媛华, 等. 2018.水位升降条件下牵引式滑坡离心模型试验[J].岩土力学, 39(2): 605-613. http://d.old.wanfangdata.com.cn/Periodical/ytlx201802025 时卫民, 郑颖人, 唐伯明. 2003.滑坡稳定性评价方法的探讨[J].岩土力学, 24 (4): 545-548, 552. http://d.old.wanfangdata.com.cn/Periodical/ytlx200304011 苏永华, 李帅, 方砚兵, 等. 2019.基于上限分析的边坡稳定可靠性评估[J].工程地质学报, 27(2): 451-458. doi: 10.13544/j.cnki.jeg.2017-339 陶志刚, 赵俊凯, 张海江, 等. 2017.坡顶加载对缓倾顺层边坡稳定性影响规律研究[J].煤炭技术, 36(3): 64-67. http://d.old.wanfangdata.com.cn/Periodical/mtjs201703024 王根龙, 伍法权, 门玉明. 2006.基于土质边坡塑性极限分析条分法的可靠度计算方法研究[J].工程地质学报, 14(6): 835-840. http://www.gcdz.org/article/id/9068 徐文杰, 王立朝, 胡瑞林. 2009.库水位升降作用下大型土石混合体边坡流-固耦合特性及其稳定性分析[J].岩石力学与工程学报, 28(7): 1491-1498. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb200907024 杨帆, 许强, 范宣梅, 等. 2019.基于时间序列与人工蜂群支持向量机的滑坡位移预测研究[J].工程地质学报, 27(4): 880-889. doi: 10.13544/j.cnki.jeg.2017-256 杨继红, 王俊梅, 董金玉, 等. 2011.水库蓄水过程中堆积体边坡瞬态稳定性分析[J].岩土力学, 32 (S1): 464-470. http://d.old.wanfangdata.com.cn/Conference/8823179 周家文, 陈明亮, 李海波, 等. 2019.水动力型滑坡形成运动机理与防控减灾技术[J].工程地质学报, 27(5): 1131-1145. doi: 10.13544/j.cnki.jeg.2019130 -