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1.
Three-dimensional slope stability analysis of South Peak, Crowsnest Pass, Alberta, Canada 总被引：2，自引：2，他引：0
Marc-Andr�� Brideau Andrea Pedrazzini Doug Stead Corey Froese Michel Jaboyedoff David van Zeyl 《Landslides》2011,8(2):139-158
South Peak is a 7-Mm3 potentially unstable rock mass located adjacent to the 1903 Frank Slide on Turtle Mountain, Alberta. This paper presents
three-dimensional numerical rock slope stability models and compares them with a previous conceptual slope instability model
based on discontinuity surfaces identified using an airborne LiDAR digital elevation model (DEM). Rock mass conditions at
South Peak are described using the Geological Strength Index and point load tests, whilst the mean discontinuity set orientations
and characteristics are based on approximately 500 field measurements. A kinematic analysis was first conducted to evaluate
probable simple discontinuity-controlled failure modes. The potential for wedge failure was further assessed by considering
the orientation of wedge intersections over the airborne LiDAR DEM and through a limit equilibrium combination analysis. Block
theory was used to evaluate the finiteness and removability of blocks in the rock mass. Finally, the complex interaction between
discontinuity sets and the topography within South Peak was investigated through three-dimensional distinct element models
using the code 3DEC. The influence of individual discontinuity sets, scale effects, friction angle and the persistence along
the discontinuity surfaces on the slope stability conditions were all investigated using this code. 相似文献
2.
Evaluating Kinematic Controls on Planar Translational Slope Failure Mechanisms Using Three-Dimensional Distinct Element Modelling 总被引：1，自引：0，他引：1
This paper investigates the importance of kinematic release mechanisms on planar translational slope failure using three-dimensional distinct element codes. The importance of the dip and dip direction of the rear, basal and lateral release surfaces and their influence on failure mechanism, dilation, and the development of step-path failures is illustrated. The three-dimensional block shape and volume of the unstable rock masses simulated with the different discontinuity set geometries are characterized. Two assumed three-dimensional slope models are investigated in order to assess the importance of varying kinematic confinement/release mechanisms. These two assumed boundary conditions are shown to be critical in the development of asymmetrical rock mass deformation patterns. Scale effects due to the block size and discontinuity persistence are shown to control the calculated displacement and failure mechanisms. The numerical modelling results are also demonstrated to be sensitive to the assumed normal and shear stiffness of the discontinuities. The influence of the factors investigated on the failure of a single rock block versus a rock mass are compared and discussed. 相似文献
3.
目前运动单元法的研究主要集中于土质边坡,未涉及到岩质边坡稳定性分析问题;而岩体中孕育有不同特性的结构面,控制着岩质边坡的力学行为。为求解结构面控制作用下岩质边坡“结构面滑移-岩桥剪断”复合型破坏问题,研究了塑性滑移区节点在岩桥内和结构面上的运动约束条件,推导了含结构面的运动单元计算公式,提出了改进运动单元法。通过经典算例的对比分析,验证了改进运动单元法计算结果的准确性。研究结果表明:岩桥位置、结构面贯通度和结构面倾角是控制岩质边坡力学行为的3个主要影响因素。岩桥越接近坡顶,改进运动单元法所得安全系数越大,而Jennings法无法反映岩桥位置的影响效应。高贯通度的结构面导致岩质边坡发生“结构面滑移-岩桥剪断”复合型破坏模式,安全系数较小;而低贯通度的结构面导致完整岩石发生破坏,安全系数较大。水平或陡倾角结构面导致滑裂面穿切结构面,安全系数较大;而对于其它倾角情况下的结构面,岩质边坡发生“结构面滑移-岩桥剪断”复合型破坏模式,安全系数较小。实例应用结果说明该方法可以有效评价岩质边坡的稳定状态,可在类似工程中应用推广。 相似文献
4.
2008年5 12四川汶川里氏8级地震,引发了大量崩塌滑坡。安县高川乡的大光包滑坡是规模最大的高山滑坡,总方量约10109m3。它的形成机制和运动学特征引起国内外学者的广泛关注。在前人调查研究的基础上,本课题组对滑坡的外形和结构特征及其所处地质环境作了较详细地现场调查,系统研究了滑坡的形成和演化过程,开展了室内实验及震动台物理模拟实验,通过与类似地区地质现象的对比分析,对滑坡获得以下认识: (1)大光包滑坡是一个巨型的楔型槽状滑落体,以下伏的震旦系白云岩层面为主滑面,以与层面近于正交的早期X构造裂隙面为侧滑面,两控制面交线倾向北北东,倾角12左右; (2)滑坡前缘的黄洞子沟是滑坡的剪出口位置,滑坡起动加速滑入黄洞子沟后受到沟道左侧山梁的阻挡而迅速制动,受阻的滑坡体上部高速越过山梁冲向山坡并发展为碎屑流; (3)作为滑坡主滑面的震旦系白云岩岩层,为一经历了强烈岩溶的白云岩沙化层,强烈地震引发沙化层因突然产生的超空隙压力而流态化,这可能是导致山体突然失稳的主要原因。大光包滑坡事件可能为我们提供了地震引发山体失稳的一种新的模式,在分析研究和评价山坡的演化和稳定性时具有重要意义。 相似文献
5.
Evaluation of potential landslide damming: Case study of Urni landslide,Kinnaur, Satluj valley,India
This work aims to understand the process of potential landslide damming using slope failure mechanism,dam dimension and dam stability evaluation. The Urni landslide, situated on the right bank of the Satluj River, Himachal Pradesh(India) is taken as the case study. The Urni landslide has evolved into a complex landslide in the last two decade(2000-2016) and has dammed the Satluj River partially since year 2013,damaging ～200 m stretch of the National Highway(NH-05). The crown of the landslide exists at an altitude of ～2180-2190 m above msl, close to the Urni village that has a human population of about 500.The high resolution imagery shows ～50 m long landslide scarp and ～100 m long transverse cracks in the detached mass that implies potential for further slope failure movement. Further analysis shows that the landslide has attained an areal increase of 103,900 ± 1142 m^2 during year 2004-2016. About 86% of this areal increase occurred since year 2013. Abrupt increase in the annual mean rainfall is also observed since the year 2013. The extreme rainfall in the June, 2013; 11 June(～100 mm) and 16 June(～115 mm),are considered to be responsible for the slope failure in the Urni landslide that has partially dammed the river. The finite element modelling(FEM) based slope stability analysis revealed the shear strain in the order of 0.0-0.16 with 0.0-0.6 m total displacement in the detachment zone. Further, kinematic analysis indicated planar and wedge failure condition in the jointed rockmass. The debris flow runout simulation of the detached mass in the landslide showed a velocity of ～25 m/s with a flow height of ～15 m while it(debris flow) reaches the valley floor. Finally, it is also estimated that further slope failure may detach as much as 0.80 ±0.32 million m^3 mass that will completely dam the river to a height of 76±30 m above the river bed. 相似文献
6.
汶川地震诱发罐滩滑坡形成机制初步分析 总被引：4，自引：1，他引：3
安县罐滩滑坡由汶川地震诱发形成,发育于存在软弱基座的反倾斜坡中,体积达468×104m3。罐滩滑坡由"5.12"汶川地震及当晚暴雨诱发形成,发生时间滞后地震8 h,是典型的地震后效型滑坡。滑坡位于龙门山前山断裂带上盘,自然斜坡走向与断裂带近平行,水平距离约400 m,前山断裂带的分支断裂从坡体下部通过,并形成底部泥岩和上部白云岩的分界线。调查和分析表明,下软上硬的坡体结构是滑坡产生的基础,强烈的地质构造活动背景是其产生的重要条件,强烈的地面震动和高强度暴雨是导致产生滑坡的根本因素。滑坡的形成机制和发展过程可以分为以下3个阶段:自然斜坡的压缩-倾倒变形、震后滑面贯通阶段、滑坡整体破坏阶段。滑坡体形成沿河长400 m,纵向长880 m,平面面积1.82×105m2的滑坡堆积体,堵塞雎水河形成罐滩堰塞湖。 相似文献
7.
金沙江结合带由于地质构造发育,地震活动频繁,河谷切割强烈,岸坡高陡狭窄, 岩体极为破碎,历史上发生过多起大型滑坡堵江事件。以白格滑坡两次堵江事件（2018年10月11日、2018年11月3日）为例,采用2009年12月4日至2020年10月16日多期、多源卫星遥感数据源,通过遥感判识、对比分析等方法对滑坡体滑前斜坡变形特征、滑后滑坡堆积特征、滑后斜坡残留体变形特征进行特大型堵江滑坡链式特征遥感动态分析。根据多期遥感影像,将白格滑坡变形特征划分为早期滑动变形阶段（2009—2011年）、稳定变形阶段（2011—2015年）、快速变形阶段（2015—2017年）、剧烈变形阶段（2017—2018年）、变形破坏阶段（2018年以后）等5个阶段。根据滑坡第一次滑后的变形破坏特征,将滑坡划分为滑源区、铲刮区、堆积区以及拉裂变形区。根据滑坡第二次滑后的变形破坏特征,将滑坡划分为二次滑坡滑源区、二次滑坡堆积区（堰塞体）、二次铲刮（堆积）区、二次铲刮区影响区以及拉裂变形区。基于上述研究成果,对白格滑坡灾害链式特征进行总结分析,为金沙江结合带高位远程滑坡灾害链式特征研究提供参考。 相似文献
8.
斜向坡变形破坏机制的数值模拟研究 总被引：3，自引：0，他引：3
本文讨论了斜向坡的旋转式变形和破坏机制，用有限元法计算了此种斜坡中的剩余下滑力的分布方式，并以此来解释在滑动过程中发生一定旋转的原因；论文还运用离散元法，模拟了此种滑坡的滑动过程。 相似文献
9.
缓倾煤层采空区上覆山体滑坡形成机制分析 总被引：4，自引：0，他引：4
下伏采空区的缓倾斜坡,由于采空区大小、方位不同和斜坡结构特征的差异,多存在地表沉陷、拉裂、局部崩塌、滑坡等工程地质问题,常常会诱发大规模的地质灾害。马达岭滑坡发育于存在软弱夹层和煤层采空区的缓倾斜坡中,由采空区的破坏和降雨诱发形成,体积达190104m3。调查和分析表明,脆弱的地质结构和坡体下伏采空区的破坏是滑坡形成的主要原因,降雨的促进作用加速了滑坡的发生; 马达岭滑坡的破坏模式为塌落-拉裂-剪切滑移,滑坡的形成机制和发展过程可以分为以下3个阶段: 斜坡后缘拉裂阶段,滑面贯通阶段和滑坡整体破坏阶段。崩滑体崩解后顺着沟谷向下游流动,形成长1.5km的泥石流碎屑堆积区,淹没大量农田。 相似文献
10.
以贵州省开阳县鱼鳅坡滑坡为研究对象,采用颗粒流离散元（PFC3D）对其破坏运动过程进行数值模拟。采用Ball-Wall建模方法建立滑坡模型,对滑坡不同关键部位颗粒进行位移、速度监测,阐明其破坏运动特征。结果表明,降雨为鱼鳅坡滑坡的直接诱发因素。该滑坡在破坏初始阶段以蠕滑变形为主,随着变形量的增加,滑坡体不断挤压坡脚,滑坡岩土体到达应力平衡极限,坡脚产生剪切破坏,并向上牵引发展,滑坡发生整体滑动,斜坡变形破坏模式为蠕滑-拉裂,按照力学条件为牵引式破坏。滑坡滑动最高时速12.4 m/s,最大滑移80 m,滑动阶段持续50 s。研究成果可为对该类滑坡影响范围预测,以及工程措施的制定具有一定的参考意义。 相似文献
11.
西安金盆水库放水塔附近滑坡特征及成因分析 总被引：11，自引：5，他引：6
放水塔附近滑坡是金盆水库右岸原1号滑坡体下游边界段的残留体,受短期强降水因素的诱发导致坡体变形、失稳滑动。滑坡体具顺层牵引滑动特征,且平面上,不同区段变形破坏程度不同,其表现形式与坡体平面旋转有一定的相似性。坡体滑动主要受4组结构面的控制,其中的软弱片理结构面（产状1501703555）与产状为2302903555的另一组结构面构成滑坡的滑动控制面。基岩内发育的大量的软弱片理结构面,大气强降水,滑坡上部相对平缓的地貌及人类工程对地表植被环境的破坏,滑坡体下部喷护层的存在等因素的综合影响,导致了坡体的失稳滑动。 相似文献
12.
Characteristics of rapid giant landslides in China 总被引：1，自引：0，他引：1
Factual data for 70 rapid, giant landslides since 1900 show that the occurrence of these landslides was largely predisposed by tectonics, geological structures, lithology and topography, and often triggered by rainfall and earthquakes. In terms of mobile behavior, the giant landslides can be classified into three types: slides, slide-flows and flows. It is found that each type of landslide was constrained to certain geologic and topographic regimes. There are good correlations between kinematic parameters of landslides and slope geometries, which confirm the important role played by topographical condition in the mobile behavior of landslides. Moreover, it is also found that each type of landslide presents distinct geotechnical characteristics in terms of nature of the slip zone and properties of sliding mass. Brief analyses of five typical cases illustrate that landslide mechanisms can be conceptually depicted by failure mechanisms of their slip zones prior to onset of movement and following energy conversion during movement. Problems and questions related to experience in China suggest that comprehensive and systematic investigation and study on rapid giant landslides are urgently needed. 相似文献
13.
Structural and engineering geology of the East Gate Landslide, Purcell Mountains, British Columbia, Canada 总被引：3，自引：0，他引：3
The East Gate Landslide is a prehistoric landslide that was reactivated in January 1997. The slope failure took place in the lower greenschist metasedimentary units of the Precambrian Horsethief Creek Group. The Grizzly Creek Thrust is a regional overturned fault that coincides with the location of the headscarp of the East Gate Landslide. Four discontinuity sets were recognised from detailed engineering geological mapping of the headscarp and surrounding area. The main scarp of the section reactivated in 1997 was sub-divided into three structural domains based on its position within the landslide, lithology, and orientation of the discontinuity sets. Limit-equilibrium techniques, finite-difference (FLAC) and distinct-element (UDEC) codes were used to investigate the failure mechanism of the 1997 event. The results of the field observations and numerical models suggest that the 1997 failure involved a complex mechanism incorporating components of rock-slumping, bi-planar, and pseudo-circular failure that was controlled by both the orientation of the discontinuity sets and reduced rock-mass quality due to tectonic deformation. 相似文献
14.
2018年8月6日中午12时,汉源县富泉镇西沟发生大规模滑坡,约1.50×10~6 m~3松散碎块石土在前期持续降雨作用下沿西沟右岸高速滑出、解体,并在主沟道内形成堰塞坝,体积约4.00×10~5 m~3。滑坡造成1人失踪,近6.70×10~3 m~2耕地被毁,紧急转移50余人。通过现场实地调查,结合无人机航飞、三维建模、地质、地震、水文、气象等资料,对康家坡滑坡基本特征进行了调查研究,调查表明,有利的地形条件、松散的覆盖层、充沛的前期降雨入渗及溪水对坡脚的冲刷是形成滑坡的主要原因。西沟原本为一条高频泥石流沟,本文在此基础上分析了堰塞坝溃坝的可能性及灾害链成灾模式。 相似文献
15.
Assessment of a coastal landslide subjected to building loads at Sinop, Black Sea region, Turkey, and stabilization measures 总被引：1，自引：0，他引：1
《Engineering Geology》2004,75(1):69-88
The large landslides along the Black Sea shore in Turkey are well-known instability phenomena and responsible for considerable economic losses each year. The severity of the problem increased particularly in recent years as increased scarcity of land forced utilization of inherently unstable areas. In 1988, severe rainstorms at the city of Sinop on the Black Sea shore triggered ground movements on a gentle coastal slope subjected to building loads and caused extensive damage to buildings founded on the slope. Comprehensive investigations of the failure were carried out and used to establish a geotechnical model for the slide. The model allowed consideration of building loads and different groundwater conditions. In addition, the model studies were complimented by limit-equilibrium and finite-element stress analyses. The results indicated movements on a circular sliding surface through stiff clay. The toe of the landslide is located at the shoreline and remains active. The failure was probably initiated by rising groundwater level combined with surcharge loads imposed by buildings on the slope. Other contributing factors include sand extraction and coastal erosion. Remedial works are recommended involving a rockfill buttress at the toe of the slide and drainage improvements on the surface of the slope. 相似文献
16.
17.
贵州省德江县香树坪滑坡特征及形成机制研究 总被引：1，自引：0，他引：1
香树坪滑坡位于贵州省铜仁地区德江县大坪村齐心组,为大型古滑坡。滑坡边界及前缘坡下发育多条拉陷槽,滑动方向为310～335。基于滑坡区工程地质条件和滑坡变形破坏特征,建立了滑坡形成机制概念模型:在河谷形成及演化过程中,香树坪斜坡以滑移-弯曲演化。滑坡前缘拉槽LC6#和LC3#依次形成,其卸荷和临空效应导致上部坡体进一步变形。滑坡坡脚区因上部坡体进一步滑移变形而应力集中,坡体稳定性整体降低。当坡脚区失稳时滑坡发生。数值分析很好地再现了滑坡演化过程及机理。研究成果可对西部山区类似类滑坡发育条件及识别研究提供参考。 相似文献
18.
On August 27, 2014, a large-scale landslide occurred in Fuquan, Guizhou, China. This high-speed landslide caused considerable destruction; 23 people were killed, 22 were injured, and 77 houses were damaged. Field investigations, deformation monitoring, and numerical analyses have been performed to examine the characteristics and formation processes of this landslide. In the Xiaoba area, the slope showed a two-layered structure with a hard upper layer and a soft lower layer. Dolomite of the Dengying Formation in the slope front formed a locked segment controlling slope stability. Based on deformation and failure characteristics, the landslide is divided into sliding source area A and accumulation area B. The landslide is also divided into the following stages: bedding slip, tension cracking at the slope scarp, and the appearance of the locked section at the slope toe. Numerical calculations show that excavation led to maximum shear strain concentration along the interface of siltstone and slate in the middle of the slope, which became a potential sliding surface. Stress concentration and distribution of the plastic zone of the locked segment of the Dengying Formation dolomite occurred in the slope toe. Continuous rainfall caused the groundwater level to rise in the Xiaoba slope. The unfavorable geological structure was a determinant factor, and the combined effects of excavation and continuous rainfall were triggering factors that induced the landslide. The geomechanical mode for the Xiaoba landslide is sliding tension–shear failure. 相似文献
19.
Indicator kriging has been applied to the study of failure mechanisms in a mine slope in Minas Gerais, Brazil, to estimate potential failure risks in limited areas along this slope. Timbopeba Mine, Vale Company, is an open pit iron mine situated in the Quadrilátero Ferrífero, a very important mining district in Minas Gerais. A slope excavated in quartzite with a maximum height of 200 m at the time of this study, has presented many failure problems involving the sliding of blocks formed by discontinuities. These blocks are of limited size in comparison to the dimensions of the overall slope. They appear along the entire slope, wherever discontinuity orientations have led to the kinematic feasibility of these blocks. Geostatistics permits the estimation of local failure probability distributions associated to these local failures, which would not be possible with traditional statistical models. The geostatistical method employed in this study, indicator kriging, is quite suitable because it is unnecessary to assume a particular global distribution of the phenomena being modeled. The model was used for locating areas with a great tendency for sliding failure, as it considers the local spatial variability of discontinuity orientations. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
20.
Owing to the heavy rainfall, a landslide occurred at the Anqian Iron mine, at 18:00(UTC + 8) on November 24, 2019, in China. The landslide was about 3.0?×?104 m3 and caused damage to the road of transporting waste materials. Failure characteristics and the mechanism of this landslide were analyzed in this study. The landslide area was divided into three parts: the rear tension cracking area, the middle sliding deformation area, and the front colluvium area. A contact-free measuring technique using the new ShapeMetrix3D system was applied and 204 joints were analyzed based on equal-angle stereographic projection. Thus, a conceptual model of the mechanism of the landslide was constructed and the formation process of the landslide was divided into three stages: the first shearing and dislocation stage; the second sliding, front bulging, and rear tractive cracking stage; and the third local rock mass collapse and colluvium depositing stage. Numerical modeling was performed to discover the landslide mechanism by progressively reducing the shear strength of rock mass. The results showed that the original slope was stable, whereas heavy rainfall triggered the landslide, and the predicted failure surface matched closely the field investigations. The factor of safety obtained by real three-dimensional analyses was slightly higher than that obtained by plane problem analyses, and the difference was attributed to the three-dimensional effect of the landslide. This paper also presents the results obtained from the parametric analysis in order to understand the impact of shear strength parameters on the overall stability of the slope.
相似文献