A STUDY OF THE INFLUENCE OF RAINFALL ON SLOPE STABILITY ALONG THE TENDENCY OF COAL MEASURE STRATA
-
摘要: 煤系地层具有岩层软硬不均，层间胶结较差，风化速度快，遇水易软化，结构易破坏导致强度丧失等特点，特别是夹层中炭质泥岩或页岩具有强度低、易活化、易变性和渗透系数相对较小的特点，这决定了其对整体边坡的稳定性具有控制作用。文章分析了煤系地层边坡饱和、非饱和渗流降雨条件（降雨强度）、土性参数（夹层饱和渗透系数）以及边坡形状尺寸（坡脚、夹层倾角、夹层埋深）等因素对边坡渗流特点及稳定性的影响，发现软弱夹层与上下岩体渗透性差异性对边坡稳定性影响明显；软弱夹层埋置越浅，边坡越易失稳；降雨强度越大，边坡越易沿软弱夹层发生滑坡；并非坡脚越大降雨之后边坡的安全系数降低幅度就大，而是随着夹层倾角的增大，边坡的安全系数逐渐降低，边坡越易沿软弱夹层发生滑坡，这些认识对煤系地层边坡的设计和治理有重要的参考意义。Abstract: Coal strata are characterized by uneven soft and hard strata, poor interlaminar cementation, rapid weathering, being easy to soften when exposed to water, loss of strength due to structural damage and so on. In particular, the carbonaceous mudstone or shale in the interlayer has the characteristics of low strength, easy activation, volatility and relatively small permeability coefficient, which determines that it has a control effect on the stability of the overall slope. In this paper, the effects of saturated and unsaturated seepage rainfall conditions (rainfall intensity), soil property parameters (saturation permeability coefficient of interlayer) and slope shape and size (slope foot, dip angle and buried depth of interlayer) on the seepage characteristics and stability of the slope are analyzed. The results show that the difference of permeability between soft interlayer and upper and lower rock mass has obvious influence on the slope stability. The shallower the soft interlayer is, the more unstable the slope is; the higher the rainfall intensity, the easier the slope along the soft interlayer landslide. It is not that the slope safety factor decreases greatly with the increase of slope inclination, but that the slope safety factor decreases gradually with the increase of interlayer inclination, and the slope is more prone to landslide along the weak interlayer. These findings are significance reference for the design and control of coal measure stratum slope.
-
Key words:
- coal measure strata /
- soft interlayer /
- slope /
- rainfall /
- safety factor
-
图 1 模型的边界条件和降雨入渗初始条件
Figure 1. The model's boundary conditions and initial rainfall infiltration conditions
图 2 材料的土水特征曲线及渗透系数函数
Figure 2. Materials of soil water characteristic curves and permeability coefficient functions
图 3 孔隙水压力随渗透系数变化(72小时)
Figure 3. Pore water pressure changing with the permeability coefficient (72 hours)
图 4 孔隙水压力随渗透系数变化(360小时)
Figure 4. Pore water pressure changing with the permeability coefficient (360 hours)
图 5 夹层与1-1断面交点处孔隙水压力随渗透系数的变化
Figure 5. Pore water pressure at the intersection of interlayer and section 1-1 changing with the permeability coefficient
图 7 夹层不同埋深位置及观测点的设置示意图(A、B、C、D为观测点)
Figure 7. Schematic diagram of different buried depths of the interlayer and the positions of the observation points (A, B, C and D are the observation points)
图 8 1-1截面不同埋深位置降雨过程中孔隙水压力的变化
Figure 8. The change of pore water pressure under rainful at different buried depths on section 1-1
图 9 夹层不同埋深位置观测点的孔隙水压力变化
Figure 9. The change of pore water pressure at the observation points of different buried depth in the interlayer
图 10 夹层不同埋深位置降雨过程中安全系数的变化曲线图
Figure 10. The variation curves of the safety factors under the rainful at different buried depths in the interlayer
图 11 不同降雨强度在降雨结束时刻1-1断面的孔隙水压力和体积含水率变化曲线
Figure 11. The variation curves of pore pressure and volumetric water content on the section 1-1 at the end of rainfalls with different rainfall intensities
图 12 不同降雨强度在降雨结束288 h时1-1断面的孔隙水压力和体积含水率变化曲线
Figure 12. The variation curves of pore water pressure and volumetric water content on the section 1-1 288 hours after rainfalls with different rainfall intersities
图 13 不同降雨强度下边坡安全系数随时间变化曲线
Figure 13. Variation curves of slope safety factors with time under different rainfall intensities
图 14 不同开挖坡脚在降雨结束时刻1-1断面孔隙水压力和体积含水率变化曲线
Figure 14. The variation curves of pore water pressure and volumetric water content on the section 1-1 at the end of rainfalls with different excavation slope toes
图 15 不同开挖坡脚在降雨结束288 h时1-1断面孔隙水压力和体积含水率变化曲线
Figure 15. The variation curves of pore water pressure and volumetric water content on the section 1-1 288 hours after rainfalls with different excavation slope toes
图 16 降雨过程中不同开挖坡脚的边坡安全系数变化曲线
Figure 16. The varication curves of slope safety factors with different excavation slope toes under rainfalls
图 17 1-1截面降雨过程中孔隙水压力的变化
Figure 17. The variation of pore water pressure on section 1-1 under rainfall
图 18 1-1截面降雨过程中体积含水率的变化
Figure 18. The variation of volumetric moisture content on section 1-1 under rainfall
图 19 不同夹层倾角边坡降雨过程中安全系数的变化
Figure 19. The variation of slope safety factors with different interlayer inclination under rainfall
表 1 各种材料的计算参数
Table 1. The calculation parameters of various materials
材料 天然密度/(kg/m3) 有效粘聚力/kPa 有效内摩擦角/(°) 饱和渗透系数/(m/s) 岩土体 2200 75 30 5×10-6 软弱夹层 1800 20 15 1×10-7 
下载: 导出CSV
表 2 夹层饱和渗透系数对边坡渗流稳定性影响分析
Table 2. Influence of interlayer saturation permeability coefficient on seepage stability of slope
计算方案 夹层饱和渗透系数/(m/s) 岩体饱和渗透系数/(m/s) 降雨强度/(m/h) 降雨类型 计算时间 方案1 1×10-5 降雨时间:72 h 方案2 5×10-6 5×10-6 0.015 等强模型 雨后时间:288 h 方案3 1×10-7 计算时间:360 h
下载: 导出CSV
表 3 夹层不同埋深位置对边坡稳定性的影响
Table 3. Influence of different buried depths of the interlayer on the slope stability
计算方案 夹层出口距坡顶的垂直距离 降雨强度 降雨类型 计算时间 方案1 10 m 0.015 m/h 等强模型 降雨时间：72 h
雨后时间：288 h
计算时间：360 h方案2 15 m 方案3 20 m 方案4 25 m
下载: 导出CSV
表 4 降雨强度对边坡稳定性的影响
Table 4. The influence of rainfall intensity on the slope stability
计算方案 降雨强度/(m/h) 夹层饱和渗透系数/(m/s) 降雨类型 计算时间 方案1 0.005 降雨时间：72 h 方案2 0.010 1×10-7 等强模型 雨后时间：288 h 方案3 0.015 计算时间：360 h
下载: 导出CSV
表 5 不同坡脚对边坡稳定性的影响
Table 5. The influence of different slope toes on the slope stability
计算方案 坡脚 降雨强度 降雨类型 计算时间 方案1 30° 0.015 m/h 等强模型 降雨时间：72 h
雨后时间：288 h
计算时间：360 h方案2 40° 方案3 50° 方案4 60°
下载: 导出CSV
表 6 不同夹层倾角对边坡稳定性的影响
Table 6. Influence of different inclinations on the slope stability
计算方案 岩层倾角 坡角 降雨强度 降雨类型 计算时间 方案1 10° 降雨时间：72 h 方案2 20° 45° 0.015 m/h 等强模型 雨后时间：288 h 方案3 30° 计算时间：360 h
下载: 导出CSV
-
[1] 聂德新, 符文熹, 任光明, 等.天然围压下软弱层带的工程特性及当前研究中存在的问题分析[J].工程地质学报, 1999, 7(4):298~302. doi: 10.3969/j.issn.1004-9665.1999.04.002NIE Dexin, FU Wenxi, REN Guangming, et al. Analysis of engineering proerties of weak layerzone under natural confining pressure and the existing problems in present studies[J]. Journal of Engineering Geology, 1999, 7(4):298~302. (in Chinese with English abstract) doi: 10.3969/j.issn.1004-9665.1999.04.002 [2] 李育枢, 李天斌.煤系地层中炭质泥岩滑带土的初步研究[J].岩土工程技术, 2006, 20(2):88~90, 93. doi: 10.3969/j.issn.1007-2993.2006.02.010LI Yushu, LI Tianbin. Study on slip band of carbon mudstone landslide in coal measure strata[J]. Geotechnical Engineering Technique, 2006, 20(2):88~90, 93. (in Chinese with English abstract) doi: 10.3969/j.issn.1007-2993.2006.02.010 [3] 李玉寿, 马占国, 贺耀龙, 等.煤系地层岩石渗透特性试验研究[J].实验力学, 2006, 21(2):129~134. doi: 10.3969/j.issn.1001-4888.2006.02.003LI Yushou, MA Zhanguo, HE Yaolong, et al. Experimental research on permeability of rocks of coal-bearing strata[J]. Journal of Experimental Mechanics, 2006, 21(2):129~134. (in Chinese with English abstract) doi: 10.3969/j.issn.1001-4888.2006.02.003 [4] 胡昕, 洪宝宁, 杜强, 等.含水率对煤系土抗剪强度的影响[J].岩土力学, 2009, 30(8):2291~2294. doi: 10.3969/j.issn.1000-7598.2009.08.016HU Xin, HONG Baoning, DU Qiang, et al. Influence of water contents on shear strength of coal-bearing soil[J]. Rock and Soil Mechanics, 2009, 30(8):2291~2294. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2009.08.016 [5] 胡昕, 洪宝宁, 王海明, 等.高液限土和煤系土抗剪强度的水敏感性比较研究[J].四川大学学报(工程科学版), 2010, 42(1):54~59. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QK201001141279HU Xin, HONG Baoning, WANG Haiming, et al. Comparative study on the water sensitivity of shear strength of high liquid limit soil and coal-bearing soil[J]. Journal of Sichuan University (Engineering Science Edition), 2010, 42(1):54~59. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QK201001141279 [6] 王桦, 纪洪广, 程桦, 等.两淮煤系地层主要岩石单轴受压条件下的导电特性试验研究[J].岩石力学与工程学报, 2010, 29(8):1631~1638. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb201008016WANG Hua, JI Hongguang, CHENG Hua, et al. Experimental study of electrical conductivity of main rocks in strata of Huaibei and Huainan coalfield under uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering, 2010, 29(8):1631~1638. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb201008016 [7] 杨科, 袁亮, 祁连光, 等.淮南矿区11~2煤顶板岩石单轴抗压强度预测模型构建[J].岩石力学与工程学报, 2013, 32(10):1991~1998. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb201310005YANG Ke, YUAN Liang, QI Lianliang, et al. Establishing predictive model for rock uniaxial compressive strength of no.11~2 coal seam roof in Huainan mining area[J]. Chinese Journal of Rock Mechanics and Engineering, 2013, 32(10):1991~1998. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb201310005 [8] 熊德国, 赵忠明, 苏承东, 等.饱水对煤系地层岩石力学性质影响的试验研究[J].岩石力学与工程学报, 2011, 30(5):998~1006. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb201105017XIONG Deguo, ZHAO Zhongming, SU Chengdong, et al. Experimental study of effect of water-saturated state on mechanical properties of rock in coal measure strata[J]. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(5):998~1006. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb201105017 [9] 杨文军, 洪宝宁, 周邦艮, 等.砾状煤系土改良性能的试验研究[J].岩土力学, 2012, 33(1):96~102. doi: 10.3969/j.issn.1000-7598.2012.01.016YANG Wenjun, HONG Baoning, ZHOU Banggen, et al. Experimental study of improvement properties of rudaceous coal-bearing soil[J]. Rock and Soil Mechanics, 2012, 33(1):96~102. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2012.01.016 [10] 柴肇云, 郭卫卫, 康天合, 等.有机硅材料改性泥岩物性变化规律研究[J].岩石力学与工程学报, 2013, 32(1):168~175. doi: 10.3969/j.issn.1000-6915.2013.01.023CHAI Zhaoyun, GUO Weiwei, KANG Tianhe, et al. Change rules of physical property of argillaceous rock for organic silicon material modified[J]. Chinese Journal of Rock Mechanics and Engineering, 2013, 32(1):168~175. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-6915.2013.01.023 [11] Erguler Z A, Ulusay R. Water-induced variations in mechanical properties of clay-bearing rocks[J]. International Journal of Rock Mechanics and Mining Sciences, 2009, 46(2):355~370. doi: 10.1016/j.ijrmms.2008.07.002 [12] 夏红兵, 颜宝, 李栋伟.深部矿井煤系地层软岩蠕变特征试验[J].兰州大学学报(自然科学版), 2013, 49(4):564~568. doi: 10.3969/j.issn.0455-2059.2013.04.021XIA Hongbing, YAN Bao, LI Dongwei. Experiment on creep characteristics of soft rock in deep mine coal-bearing strata[J]. Journal of Lanzhou University (Natural Sciences), 2013, 49(4):564~568. (in Chinese with English abstract) doi: 10.3969/j.issn.0455-2059.2013.04.021 [13] 刘建忠, 杨春和, 李晓红, 等.万开高速公路穿越煤系地层的隧道围岩蠕变特性的试验研究[J].岩石力学与工程学报, 2004, 23(22):3794~3798. doi: 10.3321/j.issn:1000-6915.2004.22.011LIU Jianzhong, YANG Chunhe, LI Xiaohong, et al. Testing study on creep of coal rocks in the tunnel of Wankai speedway[J]. Chinese Journal of Rock Mechanics and Engineering, 2004, 23(22):3794~3798. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-6915.2004.22.011 [14] 曹运江, 黄润秋, 唐辉明, 等.某水电站高边坡煤系软弱结构面流变特性试验研究[J].岩石力学与工程学报, 2008, 27(S2):3732~3739. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb2008z2064CAO Yunjiang, HUANG Runqiu, TANG Huiming, et al. Experimental research on rheological characteristics of weak structural planes of high slopes in coal strata in a hydropower station[J]. Chinese Journal of Rock Mechanics and Engineering, 2008, 27(S2):3732~3739. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb2008z2064 [15] 吴立新, 王金庄.煤岩流变特性及其微观影响特征初探[J].岩石力学与工程学报, 1996, 15(4):328~332. doi: 10.3321/j.issn:1000-6915.1996.04.004WU Lixin, WANG Jinzhuang. Preliminary exploration to rheology and micro effect characteristics of coal[J]. Chinese Journal of Rock Mechanics and Engineering, 1996, 15(4):328~332. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-6915.1996.04.004 [16] 祝磊, 洪宝宁.粉状煤系土的物理力学特性[J].岩土力学, 2009, 30(5):1317~1322. doi: 10.3969/j.issn.1000-7598.2009.05.022ZHU Lei, HONG Baoning. Physico-mechanical characteristics of powdered soil of coal measure strata[J]. Rock and Soil Mechanics, 2009, 30(5):1317~1322. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2009.05.022 [17] 王宇航, 洪宝宁.广梧高速公路块状煤系土的物理力学特性[J].河南科学, 2014, 32(11):2309~2312. http://d.old.wanfangdata.com.cn/Periodical/hnkx201411028WANG Yuhang, HONG Baoning. Physico-mechanical properties of giant soil of coal measure strata for Guangwu high way[J]. Henan Science, 2014, 32(11):2309~2312. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/hnkx201411028 [18] 陈祖煜, 汪小刚, 杨健, 等.岩质边坡稳定分析——原理·方法·程序[M].北京:中国水利水电出版社, 2005, 157~204.CHEN Zuyu, WANG Xiaogang, YANG Jian, et al. Rock slope stability analysis:theory methods and programs[M]. Beijing:China Water & Power Press, 2005, 157~204. (in Chinese) [19] 王浩然, 黄茂松, 刘怡林.含软弱夹层边坡的三维稳定性极限分析[J].岩土力学, 2013, 34(S2):156~161. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytlx2013z2025WANG Haoran, HUANG Maosong, LIU Yilin. Three-dimensional stability analysis of slope with weak interlayer[J]. Rock and Soil Mechanics, 2013, 34(S2):156~161. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytlx2013z2025 [20] 付宏渊, 曾玲, 王桂尧, 等.降雨入渗条件下软岩边坡稳定性分析[J].岩土力学, 2012, 33(8):2359~2365. doi: 10.3969/j.issn.1000-7598.2012.08.019FU Hongyuan, ZENG Ling, WANG Guiyao, et al. Stability analysis of soft rock slope under rainfall infiltration[J]. Rock and Soil Mechanics, 2012, 33(8):2359~2365. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2012.08.019 [21] 孙萍, 薛涛, 虞玉诚.下蜀土边坡降雨型滑坡的成因分析[J].水利水电技术, 2016, 47(12):117~120. http://d.old.wanfangdata.com.cn/Periodical/slsdjs201612025SUN Ping, XUE Tao, YU Yucheng. Analysis on causation of rainfall-induced landslide of Xiashu loess slope[J]. Water Resources and Hydropower Engineering, 2016, 47(12):117~120. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/slsdjs201612025 [22] 王宇, 李晓, 张搏, 等.降雨作用下滑坡渐进破坏动态演化研究[J].水利学报, 2013, 44(4):416~425. doi: 10.3969/j.issn.0559-9350.2013.04.007WANG Yu, LI Xiao, ZHANG Bo, et al. Dynamic progressive failure evolution research on landslide under precipitation[J]. Journal of Hydraulic Engineering, 2013, 44(4):416~425. (in Chinese with English abstract) doi: 10.3969/j.issn.0559-9350.2013.04.007 [23] 秦鸿.软弱夹层边坡变形性状及其影响因素分析[J].重庆交通大学学报(自然科学版), 2011, 30(2):282~286. http://cdmd.cnki.com.cn/Article/CDMD-10335-2006070179.htmQIN Hong. Analysis of deformation characteristics and its influencing factors of slope with soft interlayer[J]. Journal of Chongqing Jiaotong University (Natural Science), 2011, 30(2):282~286. (in Chinese with English abstract) http://cdmd.cnki.com.cn/Article/CDMD-10335-2006070179.htm [24] 张社荣, 谭尧升, 王超, 等.多层软弱夹层边坡岩体破坏机制与稳定性研究[J].岩土力学, 2014, 35(6):1695~1702. http://d.old.wanfangdata.com.cn/Periodical/ytlx201406026ZHANG Sherong, TAN Yaosheng, WANG Chao, et al. Research on deformation failure mechanism and stability of slope rock mass containing multi-weak interlayers[J]. Rock and Soil Mechanics, 2014, 35(6):1695~1702. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/ytlx201406026 [25] 许宝田, 钱七虎, 阎长虹, 等.多层软弱夹层边坡岩体稳定性及加固分析[J].岩石力学与工程学报, 2009, 28(S2):3959~3964. http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb2009z2097XU Baotian, QIAN Qihu, YAN Changhong, et al. Stability and strengthening analyses of slope rock mass containing multi-weak interlayers[J]. Chinese Journal of Rock Mechanics and Engineering, 2009, 28(S2):3959~3964. (in Chinese with English abstract) http://d.old.wanfangdata.com.cn/Periodical/yslxygcxb2009z2097 [26] 祝磊, 洪宝宁.降雨作用下煤系土路堑边坡稳定分析[J].岩土力学, 2009, 30(4):1035~1040. doi: 10.3969/j.issn.1000-7598.2009.04.030ZHU Lei, HONG Baoning. Stability analysis of coal measure soil slope under rainfall infiltration[J]. Rock and Soil Mechanics, 2009, 30(4):1035~1040. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2009.04.030 [27] Fredlund D G, Morgenstern N R, Widger R A. The shear strength of unsaturated soils[J]. Canadian Geotechnical Journal, 1978, 15(3):313~321. doi: 10.1139/t78-029 [28] 弗雷德隆德D G, 拉哈尔佐H.非饱和土土力学[M].陈仲颐, 张在明, 陈愈炯, 等译.北京: 中国建筑工业出版社, 1997, 97~125.Fredlund D G, Rahardjo H. Soil mechanics for unsaturated soils[M]. CHEN Zhongyi, ZHANG Zaiming, CHEN Yujiong, et al, trans. Beijing: China Architecture & Building Press, 1997, 97~125. (in Chinese) [29] Vanapalli S K, Fredlund D G, Pufahl D E, et al. Model for the prediction of shear strength with respect to soil suction[J].Canadian Geotechnical Journal, 1996, 33:379~392. doi: 10.1139/t96-060 [30] 田卿燕, 肖春发, 吕建兵.粤北山区高速公路煤系地层滑坡机理分析[J].铁道科学与工程学报, 2008, 5(5):61~64. doi: 10.3969/j.issn.1672-7029.2008.05.013TIAN Qingyan, XIAO Chunfa, LV Jianbing. Mechanics analysis of landslide in coal measure strata slope in north Guangdong[J]. Journal of Railway Science and Engineering, 2008, 5(5):61~64. (in Chinese with English abstract) doi: 10.3969/j.issn.1672-7029.2008.05.013 [31] 李吉东.京珠高速公路小塘至甘塘段煤系地层路堑高边坡稳定性分析与防治[J].水文地质工程地质, 2003, (5):86~88. doi: 10.3969/j.issn.1000-3665.2003.05.020LI Jidong. Stability analysis and control of cutting high slopes in coal measure strata along Xiaotang-Gantang of Beijing-Zhuhai expressway[J]. Hydrogeology and Engineering Geology, 2003, (5):86~88. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-3665.2003.05.020 -
下载:
计量
- 文章访问数: 283
- HTML全文浏览量: 103
- PDF下载量: 16
- 被引次数: 0
