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1.
甚之助谷滑坡是位于日本白山地区的特大型滑坡。其长约为2000m．宽500m。滑坡由中侏罗系一早白垩系的手取层群砂岩一页岩互层组成。7年来的地表变形观测结果表明．由于变形速度的差异,该滑坡可以分成上下两个部分。上部的变形速率为80～170mm／a的速度．而下部则相对稳定(3～15mm／a)。观测数据还显示了水位变动对滑坡位移造成的明显影响。变形观测和现场观察的结果证实该边坡的顺向坡结构和互层的风化效应是该滑坡变形的最基本因素。 相似文献
2.
自2008 年三峡库区175 m试验性蓄水以来,受库水波动及强降雨影响,沿江库岸发生多起顺向古滑坡变形灾害。以三峡库区巫山县塔坪H1滑坡为例,结合近十年滑坡调查勘察与变形监测资料,分析了该滑坡蓄水后的变形特征。通过研究分析认为:（1）塔坪H1滑坡为顺层古岩质滑坡,岩体呈碎裂状,岩性主要为三叠系香溪组软硬相间的砂岩、泥页岩,岩层间夹多套软弱夹层,形成了多级滑带控制的滑坡变形。（2）滑坡变形分为3个区域,位移量变形最大的滑坡前缘消落带区域,最大水平位移已达80 cm,其次是处于缓慢变形状态的曲尺场镇前部区域和后部相对稳定的曲尺场镇区域。（3）数值模拟结果显示,库水位周期性波动影响着滑坡前缘涉水区域稳定性变化,短时强降雨沿岩体结构面入渗会加速滑坡中前部区域稳定性快速下降。在水位波动和短时强降雨的共同影响下,塔坪H1滑坡在每年汛期呈现缓慢变形。目前塔坪H1滑坡中前部处于持续变形阶段,亟需开展滑坡防治工程,提高滑坡稳定性,确保场镇安全。 相似文献
3.
The World Landslide Forum (WLF) is a triennial mainstream conference aimed at gathering scientists, stakeholders, policy makers
and industry members dealing with the management of landslide risk. The First World Landslide Forum, organised by the International
Consortium of Landslides, UNESCO, WMO, Food and Agriculture Organization, UNISDR, UNU, UNEP, IBRD, UNDP, ICSU, WFEO, KU and
the Japan Landslide Society, was held in 2008 at the United Nations University, Tokyo. The 1st WLF adopted the 2008 Tokyo
Declaration “Strengthening the International Programme on Landslides with UNISDR”. The Second World Landslide Forum has the
objective to further develop the outcomes of the First Forum in Tokyo 2008 by providing a global cross-cutting information
and cooperation platform for all types of organisations representing academia, United Nations organisations, governments,
private enterprises and individuals that contribute to landslide research, practice, education and decision making and are
willing to strengthen landslide and other related Earth system risk reduction strategies. The emphasis of this forum will
be “Putting Science into Practice” with special attention given to actual implementation of technology and research in everyday
applications and procedures with the direct involvement of researchers, engineers, private enterprises, stakeholders as well
as policy and decision makers. The abstract submission and pre-registration of participants was quite successful with 649
received abstracts and more than 800 participants at May 2011. The full organisation of the event is now in progress taking
into consideration the new figure and interest in scientific community and stakeholders. 相似文献
4.
甲西滑坡位于雅砻江中游某大型水电站水库库尾,是该区典型的一种滑坡类型。研究该滑坡的形成机制,对认识该区斜坡的变形破坏规律,评价库区斜坡的稳定性具有重要意义。该滑坡发育于由中薄层状砂岩与薄层状板岩互层组成的中陡倾角反向层状结构斜坡中,其变形破坏机制为倾倒弯曲-拉裂型。地质分析及简化毕肖普法稳定性计算结果表明,滑坡堆积体在自然状态下处于潜在不稳定状态,在特大暴雨和洪水作用下滑坡前缘有较大规模滑塌失稳的可能,但水库2 870 m蓄水位对滑坡的稳定性不起主导作用。 相似文献
5.
Numerical simulation of Qiaotou Landslide deformation caused by drawdown of the Three Gorges Reservoir,China 总被引：6，自引：2，他引：4
Jiwei Jiang Dominik Ehret Wei Xiang Joachim Rohn Ling Huang Shaojun Yan Renneng Bi 《Environmental Earth Sciences》2011,62(2):411-419
Landslides located beside reservoirs tend to be unstable or are characterized by large deformation during the drawdown process.
This has been accepted by many experts. In this paper, we use Qiaotou Landslide, which is located beside the Three Gorges
Reservoir (TGR), as a typical case study to investigate and predict the deformation mechanism during the drawdown process
of TGR in detail. According to field investigation, the landslide mass is mainly composed of thick, loose silt and clay mixed
with fragments of rock. Bedrock is mainly composed of silty sandstone. Field and laboratory tests indicate that the landslide
mass has a high permeability coefficient. If the water level declines fast, intense seepage force may result. Based on these
data, we establish a three-dimensional geological model of Qiaotou Landslide by FLAC3D and perform a numerical simulation using the saturated–unsaturated fluid–solid coupling theory. For the simulation, we assume
that the drawdown from 175 to 145 m takes place with a speed of 25 cm/day, which is based on the extreme water level regulation
program of TGR. The simulation shows that this causes a significant deformation in the landslide mass and that the maximum
displacement within the landslide is 24.2 cm. During the drawdown process, the maximum displacement zone is shifting from
the upper part of the landslide where bedrock surface is steeper and thickness of loose deposits is less to the middle part
of the landslide where bedrock surface is less steep and thickness of loose deposits is higher. The deformation mechanism
indicates that in the early stage of the drawdown the deformation of the landslide mass is mainly caused by seepage and in
the later stage mainly by consolidation. 相似文献
6.
On June 14 2008, an Iwate–Miyagi inland earthquake that had a magnitude of 7.2 hit the eastern foot of the Ohu Mountains in
Tohoku district, Japan. The seismic peak ground acceleration was greater than 1,000 gal in the Aratozawa Dam area. The earthquake
triggered a massive landslide at the upper reach of the dam. The landslide had the sediment volume of over 67 million cubic
meters and is considered the largest catastrophic landslide in Japan during the last 100 years. This report presents a summary
of our findings pertinent to the landslide’s activities based on our field investigations that started the day after the landslide.
This report covers: (1) details of the land deformations caused by the landslide, (2) geological background pertinent to landslide
development, and (3) estimation of the slip surface and the other physical properties of the landslide based on the analysis
of the boring core specimens and landform features. The landslide is roughly divided into two sections, a lower and an upper
half. The lower half moved almost simultaneously as one massive block of 700 m long, 800 m wide, and 70–80 m thick. The slip
surface had developed on the very fine sand of the alternate layer of fine-grained sandstone and siltstone. The slickensided
slip surface has a gradient of only 2°. This feature indicates that the type of the landslide movement is considered to be
a block glide. The landslide body is nearly identical to the topography of the landslide area that was developed about 50,000 years ago. This shows the possibility that the landslide was reactivated. The upper half consists of two large ridges and the broad
debris field and is 600 m long, 900 m wide, and 70–100 m thick. The maximum height of the main scarp is over 150 m. 相似文献
7.
Research and development of advanced technologies for landslide hazard analysis in Italy 总被引：2，自引：0，他引：2
Francesca Bozzano Paolo Mazzanti Alberto Prestininzi Gabriele Scarascia Mugnozza 《Landslides》2010,7(3):381-385
The Research Centre on Prediction, Prevention and Control of Georisks, "Sapienza Università di Roma" (CERI) was selected as
one of the World Centres of Excellence on Landslide Risk Reduction (WCoE) under the title of “Research and development of
advanced technologies for landslide hazard analysis in Italy” in the period 2008–2011. The present paper provides background
information on the activities carried out by the CERI, in the frame of the WCoE network. Pre-defined purposes have been achieved
by the implementation of integrated monitoring systems and early warning systems for landslides movements. The application
of GBInSAR technique for monitoring landslides interacting with infrastructures is discussed, and two case histories are presented.
It is shown that this technique is particularly suitable for the displacements monitoring of landslides interacting with infrastructures,
thanks to its peculiar features (i.e. areal mapping, operability under every weather and lighting conditions and continuous
and completely remote monitoring). Hence, it can be considered a very important tool for the reduction of risks connected
to the realisation and activity of large infrastructures. 相似文献
8.
淌里滑坡是三峡水库区地质灾害防治监测预警工程Ⅱ期专业监测点。监测方法为地表位移监测及滑体深部位移监测,同时开展长期地表宏观变形迹象监测调查。通过3a来监测资料的对比分析,各GPS变形监测点均在水平及垂直方向上有变形。即2007年2月位于滑坡前缘的WS-74、WS-75点水平位移分别达到726.91mm及170.88mm,平均年变形速率分别为340mm和80mm;位于滑体下部的WS-75钻孔滑带位置变形明显。该钻孔在2005年5月由于深部位移变形超出测试量程而无法继续监测。在2003年10月至2005年5月20个月内,该钻孔滑带位置累计位移量达46mm以上,月平均变形率达2.3mm。以此变形速率发展,至2006年12月,滑带累计位移变形量将在100mm左右。滑坡的变形集中在滑坡的前缘地带及次级滑坡,从2003年至今,宝子滩崩滑体附近已有将近20×10^4m^3的崩塌堆积层滑入江中。目前滑坡处于匀速变形阶段,为不稳定状态,滑坡区内的4户18人和宝子滩民用码头的安全受到威胁。 相似文献
9.
Landslide Hazard Zonation using Remote Sensing and GIS: a case study of Dikrong river basin, Arunachal Pradesh, India 总被引：3，自引：0，他引：3
Landslides are among the most costly and damaging natural hazards in mountainous regions, triggered mainly under the influence
of earthquakes and/or rainfall. In the present study, Landslide Hazard Zonation (LHZ) of Dikrong river basin of Arunachal
Pradesh was carried out using Remote Sensing and Geographic Information System (GIS). Various thematic layers namely slope,
photo-lineament buffer, thrust buffer, relative relief map, geology and land use / land cover map were generated using remote
sensing data and GIS. The weighting-rating system based on the relative importance of various causative factors as derived
from remotely sensed data and other thematic maps were used for the LHZ. The different classes of thematic layers were assigned
the corresponding rating value as attribute information in the GIS and an “attribute map” was generated for each data layer.
Each class within a thematic layer was assigned an ordinal rating from 0 to 9. Summation of these attribute maps were then
multiplied by the corresponding weights to yield the Landslide Hazard Index (LHI) for each cell. Using trial and error method
the weight-rating values have been re-adjusted. The LHI threshold values used were: 142, 165, 189 and 216. A LHZ map was prepared
showing the five zones, namely “very low hazard”, “low hazard”, “moderate hazard”, “high hazard” and “very high hazard” by
using the “slicing” operation. 相似文献
10.
The World Landslide Forum is a triennial mainstream conference aimed at gathering scientists, stakeholders, policy makers
and industry members dealing with the management of landslide risk. The First World Landslide Forum, organised by the International
Consortium of Landslides, UNESCO, WMO, FAO, UNISDR, UNU, UNEP, IBRD, UNDP, ICSU, WFEO, KU and the Japan Landslide Society,
was held in 2008 at the United Nations University, Tokyo. The First World Landslide Forum adopted the 2008 Tokyo Declaration
‘Strengthening the International Programme on Landslides with UNISDR’. The numerous recent disasters due to landslides show
that there is an urgent need to translate science into practical applications to assist communities, governments and disaster-relief
organisations avert and mitigate future landslide disasters. For this reason, the explicit theme of the Second World Landslide
Forum, being organised for Rome, Italy, for 3–9 October 2011, is to connect landslide scientists with landslide stakeholders
in a special landslide forum to align future innovations in landslide science and technology with the future needs of humanity
and the environment. 相似文献
11.
In 2006, a cooperation project between China Geological Survey and the Geological Survey of Canada started the monitoring
of the landslide along the deep-cut valley in the western Sichuan using integrated GPS and InSAR observation at the Jiaju
landslide. Both GPS and InSAR techniques provided complementary measurements with the GPS providing horizontal movement and
InSAR providing vertical motion. Meanwhile, InSAR images demonstrate also an effective tool to recognize new landslides in
complex steep mountain region. The GPS observations provide continuous monitoring data while InSAR data provide monthly measurements.
The differential InSAR results show a deformation information that divided the Jiaju landslide to two areas, the north and
south parts. The north part is sliding greater than the southern part in spatial domain. The sliding was faster in 2008 than
that in 2006 in time domain, suggesting a gradual increased acceleration over time. The GPS displacement data during the past
2 years show the northern part slid horizontally 55–207 mm/a and vertically −23 mm/a, while the southern part slid horizontally
12–34 mm/a; and the vertical displacement mainly moved downward 0.05 to 12 mm/a. On average, the observations from December
of 2006 to January of 2008 indicate that the northern part is sliding at 41.6 mm/a horizontally and 43.9 mm/a vertically,
while the southern part is sliding at 16.1 mm/a horizontally and 17.5 mm/a vertically. The data acquired through the GPS and
InSAR are generally comparable. Geological survey revealed some secondary landslides, cracks, and fissures within the deformation
of the Jiaju landslide that could be induced by following factors: surface water drainage, river erosion, and slope cutting
and overloading. 相似文献
12.
Geological causes and geomorphological precursors of the Tsaoling landslide triggered by the 1999 Chi-Chi earthquake, Taiwan 总被引：5，自引：0，他引：5
Masahiro Chigira Wen-Neng Wang Takahiko Furuya Toshitaka Kamai 《Engineering Geology》2003,68(3-4):259-273
The Tsaoling landslide, one of the largest landslide areas in Taiwan, has been affected by catastrophic events triggered by rain or earthquakes six times since 1862. These landslides, including that caused by the 1999 earthquake, have essentially not been reactivated old slides, but were sequential new ones that developed upslope, retrogressively. The landslide area is underlain by Pliocene sandstone and shale to form a dip slope with a bedding plane, dipping uniformly at 14°. The slip surface of the 1999 landslide was smooth and planar, parallel to the bedding plane with a slightly stepped profile; it formed within thinly alternated beds of fine sandstone and shale with ripple lamination or in a shale bed. The shale is weathered by slaking and probably by sulfuric acid, which is inferred to be one of the major causes of the intermittent retrogressive development of the landslides. The weathering was likely accelerated by the removal of overlying beds during earlier landslides in 1941 and 1942. The top margin of the 1999 landslide, in plan view, coincided with a V-shaped scarplet, which can be clearly recognized on aerial photographs taken before the landslide. This geomorphological feature indicates that this landslide had already moved slightly before its 1999 occurrence, providing precursory evidences. 相似文献
13.
On June 28, 2010, a catastrophic rock avalanche occurred after an extreme rainstorm at Guanling with N 25°59′10′′ in latitude
and E 105°16′50′′ in longitude, Guizhou, China. This rock avalanche has a long run-out distance of 1.5 km, with 1.75 million
cubic meters of debris instantly burying two villages and resulting in 99 deaths. It originated in the coal measure strata,
with the upper part of limestone and dolomite, the middle part of the sandstone with gentle inclination, and the lower part
of shale and mudstone, together locally with coals. This kind of unique structure, with hard resistant caprock overlying softer
ductile rocks, coupled with the central outflow region at the contact zone, has catastrophic potential for rock avalanches
and creates challenges for engineering geological/hydrogeological analysis. The topography showed that the hillside slopes
were steeper at the upper portion but gentler in the lower portion, looked like the shape of a “boot.” The upper steep landform
easily led to slope instability due to its high static shear stresses, and the wide middle and lower parts provided kinematic
conditions for long run-out. Transformation of the larger potential energy into kinetic energy contributed to the formation
of a rapid long run-out rock avalanche. The rainfall from June 27 to 28 was the apparent trigger of this catastrophic avalanche.
The measured rainfall of more than 310 mm within 24 h exceeded the local historical records that were recorded over the last
60 years. The pore pressure on discontinuities of sandstone had an effect on the slope stability. The valley runoff supplied
a saturated base for the long run-out debris, inducing an additional increase of the terminus distance and the increased velocity
of the avalanche movement. 相似文献
14.
我国滑坡灾害发生频繁,但滑坡的变形预测预报一直是难题,因此每年都因滑坡的变形破坏导致重大的人员伤亡和财产损失。以三峡库区八字门滑坡为研究对象,基于十多年的监测数据分析,研究分析了该滑坡的变形特征:八字门滑坡变形的主要影响因素为降雨和库水位下降,并且累积位移曲线具有"阶跃型"的变形特征。当外界因素去除或者减小的情况下,累积位移-时间曲线将变得平稳。根据此特性,选取每年变形曲线"阶跃段"（6~8月份）的监测数据,以累积位移为目标函数,基于一元线性回归模型,对八字门滑坡2004年到2017年同期的滑坡监测数据进行分析。结果表明:一元线性回归模型能够很好地模拟八字门滑坡"阶跃段"的变形过程,此变形阶段累积位移与时间呈线性关系,直线斜率基本相同。根据此线性关系,对滑坡的累积位移进行了预测,结果表明与实际监测数据相比较,预测误差在±5 mm以内,相对误差在1%以下,精度可以满足滑坡监测预警要求,可以为八字门滑坡的防治工作提供参考。 相似文献
15.
舟曲是我国滑坡灾害最严重的地区之一,其中断裂带滑坡活动频繁,危害巨大。文章在综合遥感、变形监测和现场调查的基础上,研究了断裂带滑坡特征及其灾害效应,提出了风险防控对策。研究表明：（1）断裂带滑坡形态上主要为长条形和簸箕形;滑体、滑床一般为板岩、千枚岩碎块石组成,滑带土为含砾黏土;滑坡具有多级、分块活动特征且块体差异性滑动特征显著;滑坡一般为慢速滑动,具有蠕滑特征;滑坡具有降雨敏感性特征,深层滑坡对降雨响应有明显的滞后性。（2）断裂带滑坡的成灾模式主要为慢速滑动过程中的蠕滑拉裂效应和冲击推挤效应,滑动后的堵江淹没效应、挤压侵蚀效应,以及社会影响效应等。（3）断裂带滑坡规模较大,地层破碎,治理条件差,工程治理措施难以奏效。但其突发性不强,应以管防为主,宜采取用地管控、监测预警、避险搬迁等防治措施,慎用工程治理措施。 相似文献
16.
Modeling and monitoring in a soft argillaceous shale tunnel 总被引：1，自引：1，他引：0
Taking advantage of measurements from an in situ monitoring program and an elastoplastic model using the finite-difference
method, this paper simulates and evaluates the deformation and stability of a tunnel in soft argillaceous shale. The elastoplastic
model is implemented in FLAC3D program to simulate the deformation and the stress of the soft argillaceous shale during construction.
In situ tests performed in the soft argillaceous shale tunnel show that the results from numerical simulations are in good
quantitative agreement with the measured in situ data. Results of the simulations also suggest that deformation rate is high
during the initial phase of tunnel excavation, compared with the later phase, but the time to reach a steady state remains
long. Entire primary support has been undergoing plastic deformation before construction of the secondary lining, which takes
the form of so-called “shear yield” from the middle to the bottom of the arch. Some auxiliary measures, especially the anchor,
should be applied to enhance stabilization because of the large compressive stress located at the arch springing of the tunnel.
The methodology applied in this article can be used to investigate the effect of construction on the performance of tunnels
in soft argillaceous shale. 相似文献
17.
G.M.E. Kamh 《Environmental Geology》2005,48(4-5):625-638
The weathering factors act on the recent and archaeological sites through different processes based on the dominant environmental
conditions. The net result of weathering is deformation of the original form of construction rock. In the current case study,
the main aim is to find out the mechanism of formation of two different weathering forms recorded on many old buildings taking
Chester City as a case study. The construction rock in the case study is arenitic sandstone with carbonate content ranging
from 0.0 to 15.6%. The sandstone blocks are cemented together by hydraulic lime mortar that can easily be altered chemically
to salts by acid rain that dominates at the study area. In case of mortar with worse geotechnical limits than the sandstone
blocks, the net result is convex “domal” shape blocks, but in case of mortar with better geotechnical limits than the construction
sandstone, the net result of weathering is tafoni “concave” weathering form. 相似文献
18.
Relations between hydrology and velocity of a continuously moving landslide—evidence of pore-pressure feedback regulating landslide motion? 总被引：1，自引：0，他引：1
We measured displacement, pore-water pressure, and climatic conditions for 3 years at the continuously moving Slumgullion
landslide in Colorado, USA. The landslide accelerated when pore-water pressure increased within the landslide body, but this
occurred as pore-water pressure decreased along the landslide margin. The decrease probably occurred in response to shear-induced
soil dilation at rates greater than pore-pressure diffusion and likely increased resistance to shear displacement and resulted
in landslide deceleration. This dilative strengthening has been experimentally observed and explained theoretically, but not
previously identified during field studies. Although landslide displacement should have exceeded that required to achieve
critical-state density of shear boundaries, observed relocation of these boundaries indicates that shearing is episodic at
fixed locations, so it permits renewed dilative strengthening when “fresh” soil is sheared. Thus, dilatant strengthening may
be a considerable mechanism controlling landslide velocity, even for landslides that have continuously moved great distances. 相似文献
19.
Mechanism of creep movement caused by landslide activity and underground erosion in crystalline schist, Shikoku Island, southwestern Japan 总被引：12，自引：0，他引：12
The mechanism of creep movement of the Zentoku landslide in crystalline schist has not been studied in detail because of the steepness of the slope, very slow movement, low population density and complex topographic and geologic characteristics. Sassa et al. (1980: Proc. INTERPRAEVENT 1, 85–106) and Sassa (1984: Proc. 4th International Symp. on Landslides, Toronto, vol. 2, pp. 179–184; 1985. Geotechnical classification of landslides, Proc. 4th International Conference and Field Workshop on Landslides, Tokyo, pp. 31–40; 1989: Landslide News, Japan Landslide Society, No. 3, pp. 21–24) monitored landslide movement and groundwater level at the Zentoku landslide on Shikoku Island, southwestern Japan, and suggested that the mechanism may be caused by underground erosion. To study the influence of underground erosion at this site, continual monitoring of suspended sediment and water discharge from a groundwater outlet (i.e. a spring) was implemented. The locations of groundwater flow paths were determined, as were the amounts of discharged sediment. Slope deformation was monitored by means of a borehole inclinometer. The conclusions were as follows: (1) the flow paths were found to be on or above the shear zones in which underground erosion has occurred; (2) in addition to being a result of precipitation and groundwater discharge, sediment discharge is affected by landslide activity; and (3) the mechanism of creep movement is an interrelated chain process that combines underground erosion caused by landslide activity with landslide activity caused by underground erosion. Thus, landslide activity increases erosion susceptibility and transportation of soils within the mass, and underground erosion causes instability of the landslide mass, in turn.
This mechanism can explain the observed phenomenon that the Zentoku landslide not only moves actively during heavy rain, but also continues to creep throughout the year. 相似文献
20.
采用2004年云阳县滑坡监测数据和降雨量资料,统计了滑坡与降雨的关系。并以杨柳磅滑坡、裂口山滑坡为例,对其深部位移、地表变形与降雨的关系进行了初步分析。云阳县位于三峡西段,为地质灾害多发区。该县每年5月进入雨季,降雨次数增多,降雨强度加大。2004年暴雨有9次,每次都使滑坡出现了异常。特别是6月和9月暴雨,造成了地表较大的宏观变形。变形出现最多的月份与暴雨出现频次最多的月份相一致。随着降雨强度加大,滑坡数明显增多。研究表明当降雨量大于10mm以上时,就有滑坡出现裂缝、错台及深部位移;当降雨量在50mm以上时,滑坡异常的情况增多,甚至出现土流;平缓的地层在暴雨后易形成极大的孔隙水压力而导致滑坡活动;同时,由于页岩、泥岩遇水后易泥化、软化,产生了顺层滑动;大暴雨后,丰富的地表水渗入地下,突然增大的地下水使结构松散的堆积体含水量增加、岩土强度指标降低,造成了局部变形。由于受地理环境等多方面因素的影响,滑坡体的规模与降雨强度大小没有明显的规律。根据宏观地质调查和钻探资料,裂口山滑坡、杨柳磅滑坡上部地层有超过15m厚的粉质粘土夹块石,下部地层有碎裂砂岩和泥岩。在降雨较大的情况下,水通过裂隙进入,使泥岩、粘土层变软,容易失稳。 相似文献