The deformation mechanism analysis of gently inclined and consequent sliding-buckling rock landslides based on PFC2D
-
摘要: 川东红层地区岩层倾角通常较缓，在缓倾顺向斜坡上出现了一种较为特殊的滑移-溃屈变形破坏形式。相对于缓倾岩层的顺层滑移，其破坏、受力和变形显得较为复杂。本文在分析兴浪坡滑坡变形模式的基础上，基于PFC2D软件对其进行破坏过程及微观力学分析。结果显示：受川东宽缓褶皱影响滑坡所处地形呈上陡下缓的特点，岩层变缓和老滑坡堆积造成的应力集中是斜坡发生滑移-溃曲的原因。变形破坏模式解析其分为滑移-弯曲鼓胀、强烈弯曲-隆起和滑移-溃屈破坏3个阶段。模型破坏云图位移显示滑坡中部监测点2位置存在应力集中导致的岩体错断和剪断特征，与实际调查相符合。滑坡中部溃曲处在滑动前主要表现为压应力集中，当应力集中到一定程度，岩体沿着层面或破碎带剪切贯通，形成滑移-弯曲-溃曲变形模式。研究结果对于其他类似边坡的稳定性评价和识别具有参考意义。Abstract: The dip angle in the red bed of eastern Sichuan is generally relatively small， a special form of sliding-buckling deformation appears on the gently inclined and consequent slope. Compared to bedding-sliding， its failure、 stress and deformation are more complicated. In this paper， based on the analysis of the deformation mode of Xinglang slope， the damage process and micromechanical analysis are carried out based on PFC2D software. The results revealed that： due to the topographic features of steep at the top and slow at the bottom which affected by the wide and gentle folding in east Sichuan， the main reason why the sliding-buckling happens is the stress concentration caused by the gentle rock stratum and old landslide accumulation. The deformation damage mode is analyzed into three stages： sliding-bending bulging， strong bending-bulging and sliding-buckling. The displacement of the model damage nephogram shows that the rock body faults and shear characteristics due to stress concentration exist at the location of monitoring point 2 in the middle of the landslide， which is consistent with the actual investigation. The central buckling of the landslide shoed compressive stress concentration before sliding， when the stress concentrated to certern degree， the rock mass sheared along the bedding or the break zone， by which the deformation pattern of sliding-bending-buckling formed. The research has referrencical significance for the stability evaluation of other similar slope.
-
-
[1] 陈祖煜，汪小刚，杨健，等.岩质边坡稳定性分析——原理·方法·程序［M］.北京：中国水利水电出版社，2005.CHEN Zuyu， WANG Xiaogang， YANG Jian， et al. Rock Slope Stability Analysis—Theory，Methods，Programs［M］. Beijing： China Water Power Press， 2005.
[2] [2] 王宇，李晓，王声星，等.滑坡渐进破坏运动过程的颗粒流仿真模拟［J］.长江科学院院报，2012，29（12）：46-52.
WANG Yu， LI Xiao， WANG Shengxing， et al. Grain flow simulation of landslide progressive failure movement process［J］. Journal of the Yangtze River Academy of Sciences， 2012，29（12）：46-52.
[3] [3] 曾远.土体破坏细观机理及颗粒流数值模拟［D］.上海：同济大学，2006.ZENG Yuan. Micro mechanism of soil failure and numerical simulation of Grain flow［D］. Shanghai： Tongji University， 2006.
[4] [4] 周健，王家全，曾远，等.土坡稳定分析的颗粒流模拟［J］.岩土力学，2009，30（1）：86-90.
ZHOU Jian， WANG Jiaquan， ZENG Yuan， et al. Grain flow simulation of soil slope stability analysis［J］. Geotechnical Soil mechanics， 2009，30（1）：86-90.
[5] [5] 肖拥军，邓敏，杨昌才.库岸复杂滑坡体形成机制的数值分析［J］.自然灾害学报，2015，24（2）：74-80.
XIAO Yongjun， DENG Min， YANG Changcai. Numerical analysis of the formation mechanism of complex landslides on reservoir banks［J］. Journal of Natural Disasters， 2015，24（2）：74-80.
[6] [6] Salmi E F. Slope stability assessment using both empirical and numerical methods： A case study［J］. Bulletin of Engineering Geology and the Environment， 2015，74：13-25．
[7] [7] Li Q， Zhang Z Y. Mechanism of buckling and creep-buckling failure of the bedding rockmass on the consequent slope［C］.
Proceeding of the 6th International Congress of IAEG ， Rotterdam： A A Balkema， 1990：257-260.[8] [8] 陈自生.浅论拱溃型顺层岩质滑坡［J］.山地研究，1991，9（4）：231-235．
CHEN Zisheng. A discussion on yield-break landslide of bedding rock［J］. Journal of Mountain Research， 1991，9（4）：231-235．
[9] [9] 黄润秋，赵松江，宋肖冰，等.四川省宣汉县天台乡滑坡形成过程和机理分析［J］.水文地质工程地质，2005，（1）：13-15
.HUANG Runqiu， ZHAO Songjiang， SONG Xiaobing， et al. Analysis of landslide formation process and mechanism in Tiantai Township， Xuanhan County， Sichuan Province［J］. Hydrogeology & Engineering Geology， 2005（1）：13-15
[10] [10] 李强，张倬元.顺向斜坡岩体弯曲及蠕变-弯曲破坏机制［J］.成都地质学院学报，1990（4）：97-103.
LI Qiang， ZHANG Zhuoyuan. Bending and creep-bending failure mechanism of rock mass on the consequent slope［J］. Journal of Chengdu Institute of Geology， 1990（4）：97-103.
[11] [11] 魏玉峰，聂德新，吕生弟，等.溃曲软硬相间顺层斜坡滑移-弯曲破坏机制分析［J］.成都理工大学学报（自然科学版），2009，36（3）：287-291.
WEI Yufeng， NIE Dexin， Shengdi LÜ， et al. The mechanism analysis of sliding-bending destruction mode of consequent bedded slope in the alternatively distributed soft and hard rock layers［J］. Journal of Chengdu University of Technology （Natural Science Edition）， 2009，36（3）：287-291.
[12] [12] 陈达，许强，郑光，等.顺层边坡溃曲变形形成条件及其与层面倾角的关系［J］.科学技术与工程，2021，21（7）：2616-2625.
CHEN Da， XU Qiang， ZHENG Guang， et al. Formation of buckling along bedding and its relationship with bedding dip ［J］. Science and Technology and Engineering， 2021，21（7）：2616-2625.
[13] [13] 陈全明，方琼，罗冠枝，等.缓倾顺层岩质斜坡破坏条件和变形机制分析［J］.中国地质灾害与防治学报，2020，31（2）：19-32.
CHEN Quanming， FANG Qiong， LUO Guanzhi， et al. Failure conditions and mechanism of the gentle dip bedding slopes ［J］. Chinese Journal of Geological Hazards and Prevention， 2020，31（2）：19-32.
[14] [14] 闫国强，黄波林，王勋，等.基于岩体劣化顺层灰岩岸坡滑移-弯曲失稳机理和评价［J］.工程地质学报，2021，29（3）：668-679.
YAN Guoqiang， HUANG Bolin， WANG Xun， et al. Sliding-ending failure mechanism and evaluation of bedding limestone bank slope baserd on rockmass deterioration in Three Gorges Reservoir area［J］. Journal of Engineering Ceology， 2021，29（3）：68-679.
[15] [15] 余姝，张枝华，黄波林.三峡库区青石-抱龙段顺层灰岩库岸坡变形破坏机理［J］.中国地质灾害与防治学报，2019，30（3）：19-23.
YU Shu， ZHANG Zhihua， HUANG Bolin. Deformation mechanism of bedding limestone bank slope from Qingshi to Baolongthe Three Gorges Area［J］. Chinese Journal of Geological Hazards and Prevention， 2019，30（3）：19-23.
[16] [16] 王秋生，张瑞涛，郑宏.Malvern Hills边坡溃曲破坏分析及数值流形法模拟［J］.岩土力学，2022，32（7）：1951-1960.
WANG Qiusheng， ZHANG Ruitao， ZHENG Hong. Buckling failure analysis and numerical manifold method simulation for Malvern Hills slope［J］. Rock and Soil Mechanics， 2022，32（7）：1951-1960.
-
计量
- 文章访问数: 410
- PDF下载数: 37
- 施引文献: 0
下载: