Analysis on the response of the dip slope with weak layer to earthquake
-
摘要: 以抚顺西露天矿南帮含弱层顺向坡作为参考原型,利用FLAC 3D软件模拟实际地震动及地震动输入、斜坡模型的边界条件、岩体参数以及网格模型划分,对含弱层顺向坡进行数值模拟计算,通过监测点的加速度和速度探讨含弱层顺向坡在地震作用下的响应规律。研究结果表明:(1)地震作用下对于含单一弱层斜坡响应特征起到决定性的影响因素是弱层的厚度,在地震荷载作用下影响斜坡的稳定程度要大于单一弱层倾角的影响。(2)通过弱层与斜坡坡面的相交部位监测点2#在水平方向速度可以得出,厚度对于X方向的速度大小影响程度较大。(3)对于地震作用下双弱层特性斜坡的响应规律分析时,弱层与斜坡相交部位的破坏响应规律会随着坡高的增大而有所变化,双弱层监测点3#的加速度幅值变化及速度变化程度均比双弱层监测点2#明显。地震作用下顺向坡的响应规律与含有弱层的倾角、厚度和弱层的数量位置有关,在对斜坡的治理与防护的过程中应当充分考虑地震与弱层特性的耦合作用对斜坡稳定性的影响。Abstract: Taking the down-slope with weak strata in the south of Fushun West open-pit mine as the reference prototype, numerical simulations of the down-slope with weak strata were conducted through FLAC 3D software, which included the simulation of actual ground motion and ground motion input, the boundary conditions of slope model, rock mass parameters, and grid model division. The response rule of down-slope with weak strata under an earthquake was investigated by analyzing the acceleration and velocity of the monitoring points. The results revealed that: (1) The thickness of the weak layer is a critical factor affecting the response characteristics of the slope with a single weak layer under an earthquake, and it has a greater impact on the stability of the slope under earthquake load than the dip angle of a single weak layer. (2) Based on the horizontal velocity of monitoring point 2# at the intersection of the weak layer and the slope surface, it was concluded that the thickness has a significant influence on the velocity in the X direction. (3) The failure response law at the intersection of weak layers and slope changes with an increase in slope height when analyzing the response law of the double weak layer characteristic slope under an earthquake. The acceleration amplitude and velocity change degree of monitoring point 3# with double weak layers are more noticeable than that of monitoring point 2#. The response law of the down-slope under an earthquake is related to the dip angle, thickness, number, and location of weak layers. Therefore, the coupling effect of earthquake and weak layer characteristics on slope stability should be thoroughly considered in the process of slope treatment and protection.
-
Key words:
- weak layer /
- dip slope /
- earthquake action /
- response law
-
表 1 岩体材料力学参数
Table 1. Mechanical parameters of rock mass materials
介质 密度
$ \rho $(kg/m3)弹性模量
$ E $(GPa)泊松比
$ \mu $粘聚力
$ C $(MPa)内摩擦角
$\varphi$抗拉强度
$ {\sigma _r} $(MPa)岩体 2900 10 0.20 0.20 39.0 3.5 软弱夹层 2400 1.076 0.30 0.22 21.6 0.75 -
[1] 钱海涛,张力方,修立伟,等. 中国地震地质灾害的主要类型与分布特征[J]. 水文地质工程地质,2014,41(1):119 − 127. [QIAN Haitao,ZHANG Lifang,XIU Liwei,et al. Types and distribution characteristics of earthquake induced geological disasters in China[J]. Hydrogeology & Engineering Geology,2014,41(1):119 − 127. (in Chinese with English abstract) [2] 闫孔明,刘飞成,朱崇浩,等. 地震作用下含倾斜软弱夹层斜坡场地的动力响应特性研究[J]. 岩石力学与工程学报,2017,36(11):2686 − 2698. [YAN Kongming,LIU Feicheng,ZHU Chonghao,et al. Dynamic responses of slopes with intercalated soft layers under seismic excitations[J]. Chinese Journal of Rock Mechanics and Engineering,2017,36(11):2686 − 2698. (in Chinese with English abstract) [3] 黄润秋,余嘉顺. 软弱夹层的地震动强度效应研究[J]. 自然科学进展,2003,13(11):1177 − 1181. [HUANG Runqiu,YU Jiashun. Study on intensity effect of ground motion of weak interlayer[J]. Progress in Natural Science,2003,13(11):1177 − 1181. (in Chinese) [4] 陈国兴,陈继华. 软弱土层的厚度及埋深对深厚软弱场地地震效应的影响[J]. 世界地震工程,2004,20(3):66 − 73. [CHEN Guoxing,CHEN Jihua. The effect of depth and thickness of soft soil layer on earthquake response for deep soft sites[J]. World Information on Earthquake Engineering,2004,20(3):66 − 73. (in Chinese with English abstract) [5] 刘小丽,周德培. 有软弱夹层岩体边坡的稳定性评价[J]. 西南交通大学学报,2002,37(4):382 − 386. [LIU Xiaoli,ZHOU Depei. Stability evaluation of rock mass slope with weak intercalated layers[J]. Journal of Southwest Jiaotong University,2002,37(4):382 − 386. (in Chinese with English abstract) doi: 10.3969/j.issn.0258-2724.2002.04.007 [6] 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(增刊2): 3959 − 3964XU 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(Sup 2): 3959 − 3964. (in Chinese with English abstract) [7] 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(增刊2): 156 − 160WANG Haoran, HUANG Maosong, LIU Yilin. Three-dimensional stability analysis of slope with weak interlayer[J]. Rock and Soil Mechanics, 2013, 34(Sup 2): 156 − 160. (in Chinese with English abstract) [8] 刘汉香,许强,周飞,等. 含软弱夹层斜坡地震动力响应特性的振动台试验研究[J]. 岩石力学与工程学报,2015,34(5):994 − 1005. [LIU Hanxiang,XU Qiang,ZHOU Fei,et al. Shaking table test for seismic responses of slopes with a weak interlayer[J]. Chinese Journal of Rock Mechanics and Engineering,2015,34(5):994 − 1005. (in Chinese with English abstract) [9] 刘汉香,许强,侯红娟. 岩性及岩体结构对斜坡地震加速度响应的影响[J]. 岩土力学,2013,34(9):2482 − 2488. [LIU Hanxiang,XU Qiang,HOU Hongjuan. Influence of lithology and rock structure on slope seismic acceleration responses[J]. Rock and Soil Mechanics,2013,34(9):2482 − 2488. (in Chinese with English abstract) [10] 周飞,许强,刘汉香,等. 地震作用下含水平软弱夹层斜坡动力响应特性研究[J]. 岩土力学,2016,37(1):133 − 139. [ZHOU Fei,XU Qiang,LIU Hanxiang,et al. An experimental study of dynamic response characteristics of slope with horizontal weak interlayer under earthquake[J]. Rock and Soil Mechanics,2016,37(1):133 − 139. (in Chinese with English abstract) [11] 李慧,石乃鑫,杜永峰. 含软弱夹层边坡的地震时程响应分析[J]. 低温建筑技术,2010,32(8):54 − 56. [LI Hui,SHI Naixin,DU Yongfeng. Seismic time-history responese analysis of rock slope containing soft soil layer[J]. Low Temperature Architecture Technology,2010,32(8):54 − 56. (in Chinese with English abstract) [12] 杨乾,杨庆华,姚锦涛. 含软弱夹层场地中埋地管道的地震反应特性研究[J]. 防灾减灾工程学报,2020,40(4):520 − 526. [YANG Qian,YANG Qinghua,YAO Jintao. Seismic response characteristics of the buried pipeline in soil with soft interlayer[J]. Journal of Disaster Prevention and Mitigation Engineering,2020,40(4):520 − 526. (in Chinese with English abstract) [13] 王学伍,张彦君,万驰,等. 地震作用下含软弱夹层的顺倾岩质边坡加速度放大效应探究[J]. 水利与建筑工程学报,2019,17(3):37 − 41. [WANG Xuewu,ZHANG Yanjun,WAN Chi,et al. Acceleration amplification effects of bedding rock slope with weak interlayer under earthquake[J]. Journal of Water Resources and Architectural Engineering,2019,17(3):37 − 41. (in Chinese with English abstract) [14] 周逸飞,刘汉香,朱星,等. 含软弱夹层岩质边坡的模态分析及其对边坡地震动力响应影响的初步研究[J]. 地震工程与工程振动,2020,40(1):223 − 232. [ZHOU Yifei,LIU Hanxiang,ZHU Xing,et al. Modal analysis of rock slope with a weak interlayer and its influence on seismic dynamic response of slope[J]. Earthquake Engineering and Engineering Dynamics,2020,40(1):223 − 232. (in Chinese with English abstract) [15] 安晓凡,李宁,孙闻博. 岩质边坡倾倒变形机理及稳定性研究综述[J]. 中国地质灾害与防治学报,2018,29(3):1 − 11. [AN Xiaofan,LI Ning,SUN Wenbo. Review on the mechanism and stability of toppling deformation of rock slopes[J]. The Chinese Journal of Geological Hazard and Control,2018,29(3):1 − 11. (in Chinese with English abstract) [16] KAWAMURA S,KAWAJIRI S,HIROSE W,et al. Slope failures/landslides over a wide area in the 2018 Hokkaido Eastern Iburi earthquake[J]. Soils and Foundations,2019,59(6):2376 − 2395. doi: 10.1016/j.sandf.2019.08.009 [17] 王来贵,向丽,赵娜,等. 地震作用下顺倾多弱层岩质边坡动力响应[J]. 中国地质灾害与防治学报,2021,32(6):18 − 25. [WANG Laigui,XIANG Li,ZHAO Na,et al. Dynamic response of down-dip multi-weak-layer rock slope under earthquake[J]. The Chinese Journal of Geological Hazard and Control,2021,32(6):18 − 25. (in Chinese with English abstract) [18] 陈育民, 徐鼎平. FLAC/FLAC3D基础与工程实例[M]. 2版. 北京: 中国水利水电出版社, 2013CHEN Yumin, XU Dingping. FLAC/FLAC3D foundation and engineering example[M]. 2nd ed. Beijing: China Water & Power Press, 2013. (in Chinese with English abstract) [19] 刘红帅, 齐文浩, 郑桐. 强震动作用下顺倾和反倾岩质边坡动力响应与破坏机理[M]. 北京: 地震出版社, 2016LIU Hongshuai, QI Wenhao, ZHENG Tong. Dynamic response and failure mechanism of forward-dip and reverse-dip rock slopes under strong vibration[M]. Beijing: Seismological Press, 2016. (in Chinese with English abstract) [20] 董金玉, 杨继红, 伍法权, 等. 顺层岩质边坡加速度响应规律和滑动堵江机制大型振动台试验研究[J]. 岩石力学与工程学报, 2013, 32(增刊2): 3861 − 3867DONG Jinyu, YANG Jihong, WU Faquan, et al. Large-scale shaking table test research on acceleration response rules of bedding layered rock slope and its blocking mechanism of river[J]. Chinese Journal of Rock Mechanics and Engineering, 2013, 32(Sup 2): 3861 − 3867. (in Chinese with English abstract) [21] 谢丰蔚. 地震动记录选择和调幅方法的研究及评价[D]. 哈尔滨: 哈尔滨工业大学XIE Fengwei. Study and evaluation on selecting and scaling of ground motions[D]. Harbin: Harbin Institute of Technology. (in Chinese with English abstract) [22] 刘立平,杨实君,李英民. 软夹层参数对边坡动力特性的影响分析[J]. 重庆大学学报(自然科学版),2007,30(5):31 − 34. [LIU Liping,YANG Shijun,LI Yingmin. Influence of soft soil layer on dynamic characteristic of the slope[J]. Journal of Chongqing University (Natural Science Edition),2007,30(5):31 − 34. (in Chinese with English abstract) [23] 张谦, 李贵平. 含弱层顺倾岩质边坡稳定性影响因素分析[J]. 中国安全生产科学技术, 2022, 18(增刊1): 79 − 85ZHANG Qian, LI Guiping. Analysis of the influencing factors on stability of inclined rock slopes containing weak layers[J]. Journal of Safety Science and Technology, 2022, 18(Sup 1): 79 − 85. (in Chinese with English abstract) [24] 于龙. 含软弱夹层顺层岩质边坡地震响应与变形破坏机理研究[D]. 哈尔滨: 中国地震局工程力学研究所,YU Long. Study on seismic response and deformation failure mechanism of bedding rock slopes within weak interlayer[D]. Harbin: Institute of Engineering Mechanics, China Earthquake Administration, . (in Chinese with English abstract) -