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1.
Aurelian Catalin Trandafir Kyoji Sassa 《Geotechnical and Geological Engineering》2006,24(6):1627-1639
This paper outlines a methodology for evaluating the likelihood of catastrophic landslide occurrence on gentle slopes in liquefiable
soils during earthquake. The approach is based on a modified Newmark sliding block model of assessing the earthquake-induced
undrained landslide displacements for conditions of no shear stress reversals on the sliding surface. By employing the shear
resistance-displacement relationship from undrained monotonic ring shear tests, the simulation model incorporates the sensitivity
of computed displacements to variations in yield acceleration. The proposed approach involves an examination of undrained
seismic slope performance under various horizontal seismic waveforms scaled to different specific values of the peak earthquake
acceleration. An example problem illustrates how the proposed methodology may be used to demarcate, based on the magnitude
of permanent seismic displacement, the levels of low, moderate and high risk of catastrophic landslide on a gentle slope in
a saturated cohesionless soil susceptible to liquefaction during earthquake. 相似文献
2.
Regional landslide susceptibility following the Mid NIIGATA prefecture earthquake in 2004 with NEWMARK’S sliding block analysis 总被引：1，自引：0，他引：1
This study proposes a calculation method for regional earthquake-induced landslide susceptibility that applies the permanent seismic displacement calculated using Newmark’s sliding block analysis with estimated vertical and horizontal seismic motions. The proposed method takes into account the direction of slope failure based on the specified slope azimuth. The study results reveal the importance of predominant slope failure direction using a simple infinite slope model subjected to earthquakes. The target area for the earthquake-induced landslide susceptibility analysis constituted a region of more than 2000 km2 surrounding the epicenter of the Mid Niigata prefecture earthquake in 2004. An earthquake-induced landslide susceptibility map was created based on the proposed method with a specific combination of friction angle and cohesion, and the resulting data were compared to the landslide inventory map produced from aerial photographs following the Mid Niigata prefecture earthquake in 2004. To create the susceptibility map, geomaterial cohesion values for the slope were back-calculated to satisfy the minimum safety factor in the static state. This study also proposes a calculation method for the prediction rate and determines the back-calculated strength parameters of geomaterials. The proposed regional landslide susceptibility map will be useful for understanding potential slope failure locations and magnitude of damage, as well as for planning field investigation and preventing secondary disasters immediately after earthquakes. 相似文献
3.
4.
应用概率地震危险性评价模型进行地震滑坡危险性区划,是解决潜在地震诱发滑坡危险性评价中震源不确定性与诱发滑坡时空不确定性的有效方法 .通过理论分析,结合鲁甸地震区的实际情况,对基于力学原理的Newmark滑块位移模型与概率地震滑坡危险性分析方法中的参数的不确定性问题进行了分析,将斜坡岩土体地震作用下的强度衰减效应、地震加速度地形放大效应、断层破碎带效应融合到了斜坡累积位移计算模型中,进行了模型计算参数的优化.改进后的分析模型,更好地反映了高陡斜坡地形与断层破碎带对地震滑坡灾害发育的控制作用,在鲁甸地震区域滑坡应用中,优化模型中的滑坡失稳极高风险区与实际地震滑坡分布表现出了较好的一致性,在超越概率2%的滑坡失稳概率分布中,鲁甸地区包谷垴-小河断裂、鲁甸-昭通断裂带及牛栏江河谷地带地震滑坡高-极高风险区分布面积增幅十分显著.因此,在Newmark滑块位移模型中考虑地震动参数与岩土参数动态响应规律与变量间的定量关系,对于提高区域斜坡稳定性分析的可靠性具有重要意义. 相似文献
5.
以玉树7.1级地震诱发的玉树机场路堆积层滑坡为对象,该滑坡坡度约为10o,长×宽×厚为317 m×482 m×19.8 m,由以碎石土为主的上覆层、卵石土为主的滑动带及基岩3层组成,开展大型振动台模型试验,探究震后边坡再次承受振动荷载的能力以及地震垂直分量对坡体稳定性的贡献,分析其动力响应特征和失稳破坏机制。结果表明,强震作用下堆积层滑坡的永久变形是造成地震地质灾害的重要因素;随着输入地震荷载增大,坡脚率先破碎沉降,坡体中部产生弧形裂隙并产生沉降,坡顶出现贯穿张裂隙和剪切裂隙并向坡腰推进,表现出典型的牵引性滑坡特征;峰值加速度(PGA)、动土压力以及加速度频谱与输入地震波的强度、滑坡高程呈正相关;PGA放大系数呈现出明显的非线性特征,其变化趋势随地震荷载强度增大而减小,地震波垂直分量对滑坡PGA放大系数影响略大于水平分量。 相似文献
6.
Assessment of shallow landslide susceptibility using the transient infiltration flow model and GIS-based probabilistic approach 总被引：2，自引：0，他引：2
This study proposes a probabilistic analysis method for modeling rainfall-induced shallow landslide susceptibility by combining a transient infiltration flow model and Monte Carlo simulations. The spatiotemporal change in pore water pressure over time caused by rainfall infiltration is one of the most important factors causing landslides. Therefore, the transient infiltration hydrogeological model was adopted to estimate the pore water pressure within the hill slope and to analyze landslide susceptibility. In addition, because of the inherent uncertainty and variability caused by complex geological conditions and the limited number of available soil samples over a large area, this study utilized probabilistic analysis based on Monte Carlo simulations to account for the variability in the input parameters. The analysis was performed in a geographic information system (GIS) environment because GIS can deal efficiently with a large volume of spatial data. To evaluate its effectiveness, the proposed analysis method was applied to a study area that had experienced a large number of landslides in July 2006. For the susceptibility analysis, a spatial database of input parameters and a landslide inventory map were constructed in a GIS environment. The results of the landslide susceptibility assessment were compared with the landslide inventory, and the proposed approach demonstrated good predictive performance. In addition, the probabilistic method exhibited better performance than the deterministic alternative. Thus, analysis methods that account for uncertainties in input parameters are more appropriate for analysis of an extensive area, for which uncertainties may significantly affect the predictions because of the large area and limited data. 相似文献
7.
基于证据权法构建滑坡地质灾害评价模型,进行杭州市滑坡地质灾害危险性区划研究。主要数据源包括1930－2009年杭州市域采集到的1 905个地质灾害个例以及杭州市地质图、土地利用数据及数字高程模型（DEM）等。利用Arcgis空间分析及信息提取功能,筛选强降水、地层岩性、坡度、坡向、坡高、河网与道路缓冲等证据因子,并运用证据权法客观确定各因子权重, 最后通过Arc-WofE扩展模块对多种优选因子的叠加,计算任意格网单元的滑坡发生概率,实现对潜在滑坡点位的空间预测。经分离样本法验证,区划准确率为88.3%,分析结果与现有滑坡的分布情况比较吻合。据此表明证据权法在多指标评价及其权重确定等方面具有普适性,值得在滑坡地质灾害危险性区划等方面推广应用。 相似文献
8.
Different models were developed for evaluating the probabilistic three-dimensional (3-D) stability analysis of earth slopes
and embankments under earthquake loading using both the safety factor and the displacement criteria of slope failure. In the
3-D analysis, the critical and total slope widths become two new and important parameters. The probabilistic models evaluate
the probability of failure under seismic loading and consider the different sources of uncertainties involved in the problem,
i.e. uncertainties stemming from the discrepancies between laboratory-measured and in situ values of shear strength parameters,
randomness of earthquake occurrence, and earthquake-induced acceleration. The models also take into consideration the spatial
variabilities and correlations of soil properties. The developed models are incorporated in a computer program, PTDDSSA (probabilistic
three-dimensional dynamic slope stability analysis). These developed analysis/design procedures are incorporated within a
code named SARETL (stability analysis and remediation of earthquake-triggered landslides) that was developed in this study
for stability analysis and remediation of earthquake-triggered landslides. In addition to the dynamic inertia forces; the
developed system takes into consideration the local site effects. The code is capable of: 1. Prediction of permanent deformations
that result from landslides under seismic loading using both probabilistic and deterministic approaches. 2. The assessment
of landslide hazard that affects major transportation routes in the event of earthquakes, and the preparation of earthquake-induced
landslide hazard maps (i.e. maps that show expected displacements and probability of slope/embankments failure) for different
earthquakes magnitudes and environmental conditions. 3. Proposing a mitigation strategy against landslides and suggesting
guidelines for remedial measures. The developed expert system is applied to a major highway case study. Design maps are developed
for the highway under seismic loading.
Received: 18 March 1999 · Accepted: 11 October 1999 相似文献
9.
Influence of seismic acceleration on landslide susceptibility maps: a case study from NE Turkey (the Kelkit Valley) 总被引：2，自引：0，他引：2
Particularly in the last decade, landslide susceptibility and hazard maps have been used for urban planning and site selection of infrastructures. Most of the procedures for preparing of landslide susceptibility maps need high-quality landslide inventory map. Although the rainfall and seismic activities are accepted as triggering factor for landslides, designation of the triggering factor for each landslide in the inventory is almost impossible when well-documented records are unavailable. Therefore, during preparation of landslide susceptibility map, whole landslide records in the inventory map are used together without classifying based on the triggering factors. Although seismic activity is accepted as a triggering factor, possible effect of the use of seismic activity on production of landslide susceptibility map was investigated in this study, and the subject is open to discussion. For this purpose, a series of stability analyses based on circular failure and infinite slope model were performed considering different pseudostatic conditions. The results of analyses show that gentle slopes have higher susceptibility to failure than steeper ones, even if their stability conditions (susceptibilities) are similar for static condition. The seismic forces acting on failure surfaces may not be sufficiently taken into consideration in the conventionally prepared landslide susceptibility maps. Employing the general decreasing trend in stability condition based on slope face angle and the seismic acceleration, a new procedure was introduced for preparing of the landslide susceptibility map for a scenario earthquake. The prediction performance of occurring landslides increased after the procedure was applied to the conventionally prepared landslide susceptibility map. According to the threshold independent spatial performance analyses of the proposed methodology and the produced landslide susceptibility maps, the area under ROC curve values were calculated as 0.801, 0.933, and 0.947 for the maps prepared by considering conventional method and scenario earthquakes having M w values of 5.5 and 7.5, respectively. 相似文献
10.
Landslides are mainly triggered by decrease in the matric suction with deepening the wetting band by rainfall infiltrations. This paper reports rainfall-induced landslides in partially saturated soil slopes through a field study. A comprehensive analysis on Umyeonsan (Mt.) landslides in 2011 was highlighted. The incident involves the collapse of unsaturated soil slopes under extreme-rainfall event. Fundamental studies on the mechanism and the cause of landslides were carried out. A number of technical findings are of interest, including the failure mechanism of a depth of soil and effect of groundwater flow, the downward movement of wetting band and the increase of groundwater level. Based on this, an integrated analysis methodology for a rainfall-induced landslide is proposed in this paper that incorporates the field matric suction for obtaining hydraulic parameters of unsaturated soil. The field matric suction is shown to govern the rate of change in the water infiltration for the landslide analysis with respect to an antecedent rainfall. Special attention was given to a one-dimensional infiltration model to determine the wetting band depth in the absence of the field matric suction. The results indicate that landslide activities were primarily dependent on rainfall infiltration, soil properties, slope geometries, vegetation, and groundwater table positions. The proposed methodology has clearly demonstrated both shallow and deep-seated landslides and shows good agreement with the results of landslide investigations. 相似文献
11.
2008年汶川地震滑坡详细编目及其空间分布规律分析 总被引：3，自引：0，他引：3
最新研究成果表明, 2008年5月12日汶川MS 8.0级地震触发了超过197000处滑坡。首先,基于GIS与遥感技术构建了汶川地震滑坡的3类编目图,分别为单体滑坡面分布数据、滑坡中心点位置和滑坡后壁点位置。构建方法为基于地震前后高分辨率遥感影像的目视解译方法,区分单体滑坡并圈定其边界,对滑坡后壁进行识别与定点,并开展了部分滑坡的野外验证工作。这些滑坡分布在一个面积大约为110000km2的区域内,滑坡总面积约为1160km2。选择一个面积约为44031km2的区域作为研究区,区内滑坡数量为196007个,滑坡面积为1150.622km2,这是最详细完整的汶川地震滑坡编录成果,也是单次地震事件触发滑坡最多的记录。其次,开展研究区内的地震滑坡空间分布规律的研究。基于滑坡面与滑坡中心点分别构建滑坡空间分布面积密度图与点密度图,结果表明:滑坡多沿着映秀北川断裂分布,多发生在断裂的上盘。滑坡的高密度区位于映秀北川同震地表破裂的南西段(映秀镇与北川县之间)的上盘区域,这一区域恰对应着逆冲分量为主的断裂上盘,表明逆冲断裂对上盘区域发生滑坡的极强烈的控制作用,而该区域正是形变最大的区域,因此说明是地震滑坡发生的强烈控制作用。基于滑坡面密度(LAP)、滑坡中心点密度(LCND)与滑坡后壁点密度(LTND)这3个衡量指标,使用统计分析方法,评价了汶川地震滑坡与地震参数、地质参数、地形参数的关系。结果表明:LAP、LCND与LTND这3个衡量指标与坡度、地震烈度与PGA存在明显的正相关关系; 与距离震中、距离映秀北川同震地表破裂存在负相关关系; 斜坡曲率越接近0,滑坡越不易发生; LAP、LCND与LTND的高值高程区间为1200～3000m; 滑坡发生的优势坡向为E、SE、S方向; 滑坡发育的易发岩性为砂岩与粉砂岩(Z)、花岗岩; 滑坡与坡位的相关关系不太明显。统计结果还表明LCND与LTND两个衡量指标的差异对地震与地质因子不敏感,而对地形因子较敏感。最后将本文的统计结果与以往的汶川地震滑坡空间分布规律统计成果进行了一些对比,对比结果表明,对于某些因子,如高程、岩性、距离震中、距离映秀北川断裂的统计分析结果,采用不完整的滑坡分布数据或点数据,与采用较完整的滑坡分布面数据会有一定的差异,这种差异并未出现在针对坡度与坡向等因子的统计对比结果中。总之,作者认为一个完备、详细的地震滑坡分布面要素编目图是地震滑坡空间分布规律定量分析、危险性定量分析与滑坡控制的地震区地貌演化研究的重要基础,否则,与实际情况相比,得到统计结果会有一定的偏差,本文的研究成果与以往成果的对比结果证明了这一点。 相似文献
12.
This study embraces the formation of the limiting geometry of finite slopes under the static and seismic conditions within the slip line theory framework coupled with the modified pseudo-dynamic approach. The proposed methodology is expected to achieve a global factor of safety of 1.0 for the obtained slope profile. While analysing the stability of slopes using the limit analysis or the limit equilibrium method, the cognition of the slope geometry and the nature of the slip surface need to be known in advance. Such limitations are ruled out in the present analysis with the aid of the slip line method. Further, by employing the modified pseudo-dynamic approach, the dynamic properties of soil, such as damping ratio and frequency effect, are effectively considered in this stability analysis. The consideration of the slip line theory permits to achieve an adaptive failure mechanism in the analysis. The impact of a set of parameters characterizing the input motion and the dynamic soil properties on the behaviour of a slope explains the relevance of the present modified pseudo-dynamic approach compared to the conventional pseudo-static and the original pseudo-dynamic approaches. The proposed solution serves as a measure of the seismic slope stability in accordance with the geomorphological process generally encountered in nature. Compared with the available literature, the present results propose safe, economical, and efficient design guidelines for finite slopes and intimate the need for preventive measures to enhance the stability of existing slopes.
相似文献13.
Different models were developed for evaluating the probabilistic three-dimensional (3-D) stability analysis of earth slopes and embankments under earthquake loading. The 3-D slope stability model assumed is that of a simple cylindrical failure surface. The probabilistic models evaluate the probability of failure under seismic loading considering the randomness of earthquake occurrence, and earthquake induced acceleration and uncertainties stemming from the discrepancies between laboratory-measured and in-situ values of shear strength parameters. The models also takes into consideration the spatial variabilities and correlations of soil properties. The probabilistic analysis and design approach is capable of obtaining the 2-D and 3-D static and dynamic safety factors, the probability of slope failure, the earthquake induced acceleration coefficient, the yield acceleration coefficient, the earthquake induced displacement, and the probability of allowable displacement exceedance taking into account the local site effect. The approach is applied to a well known landslide case: Congress Street Landslide in Chicago. A sensitivity analysis was conducted on the different parameters involved in the models by applying those models to the Congress Street landslide considering different levels of seismic hazard. Also, a sensitivity analysis was carried out to study the sensitivity of computed results to input parameters of undrained shear strength, and corrective factors. A comparison was made between the different models of failure. The parametric study revealed that the hypocentral distance and earthquake magnitude have major influence on the earthquake induced displacement, probability of failure and dynamic 2-D and 3-D safety factors. 相似文献
14.
地震作用下堆积体边坡的动力响应特性十分复杂,单一抗震安全系数不足以评价其动力稳定性。通过大型振动台试验,研究了连续多级地震荷载作用下,地震波的类型、卓越频率及峰值加速度对堆积体边坡坡面永久位移的影响,并初步分析其失稳机制。试验结果表明,相同峰值加速度下振动型地震波比冲击型地震波更容易产生坡面永久位移,地震波卓越频率对坡面永久位移也有重要影响;堆积体边坡在峰值加速度apeak=0.2g时开始有大颗粒石砾滚落,对应的坡面永久位移在apeak=0.2g～0.3g之间开始产生并显著增大,另外利用考虑坡面几何形态变化的改进Newmark法对坡顶的永久位移进行了估算。通过坡面永久位移评价堆积体边坡的动力稳定性有一定合理性。 相似文献
15.
GIS-based landslide susceptibility mapping using bivariate statistical analysis in Devrek (Zonguldak-Turkey) 总被引：15，自引：10，他引：5
Devrek town with increasing population is located in a hillslope area where some landslides exist. Therefore, landslide susceptibility
map of the area is required. The purpose of this study was to generate a landslide susceptibility map using a bivariate statistical
index and evaluate and compare the results of the statistical analysis conducted with three different approaches in seed cell
concept resulting in different data sets in Geographical Information Systems (GIS) based landslide susceptibility mapping
applied to the Devrek region. The data sets are created from the seed cells of (a) crowns and flanks, (b) only crowns, and
(c) only flanks of the landslides by using ten different causative parameters of the study area. To increase the data dependency
of the analysis, all parameter maps are classified into equal frequency classes based directly on the percentile divisions
of each corresponding seed cell data set. The resultant maps of the landslide susceptibility analysis indicate that all data
sets produce fairly acceptable results. In each data set analysis, elevation, lithology, slope, aspect, and drainage density
parameters are found to be the most contributing factors in landslide occurrences. The results of the three data sets are
compared using Seed Cell Area Indexes (SCAI). This comparison shows that the crown data set produces the most accurate and
successful landslide susceptibility map of the study area. 相似文献
16.
With the development of the geographic information system (GIS), the analysis of regional slope stability under seismic loading has evolved rapidly in recent years. In many studies, the Newmark’s method is used for the computation of displacements triggered by an earthquake on a single slope, while for regional analysis, the infinite slope theory is frequently used due to its simplicity when large amount of computations are required. In this research, the infinite slope theory was examined considering various seismic conditions, material properties, and slope geometry to verify the suitability of the method when applied to regional analysis and development of potential shallow landslide maps. The landslide cases induced by Chi-Chi earthquake in central Taiwan were used in this study for verification. It was found that the infinite slope theory is valid for regional analysis when used with discretion. Based on the calculated Newmark’s displacement and combining the GIS technique, procedures for the potential map development are established in this study. 相似文献
17.
Daniel M. Hess Ben A. Leshchinsky Michael Bunn H. Benjamin Mason Michael J. Olsen 《Landslides》2017,14(5):1677-1697
Shallow landslides are a prevalent concern in mountainous or hilly regions that can result in severe societal, economic, and environmental impacts. The challenge is further compounded as the size and location of a potential slide is often unknown. This study presents a generalized approach for the evaluation of regional shallow landslide susceptibility using an existing shallow landslide inventory, remote sensing data, and various geotechnical scenarios. The three-dimensional limit equilibrium model derived in this study uses a raster-based approach that uniquely integrates tree root reinforcement, earth pressure boundary forces, and pseudo-static seismic accelerations. Contributions of this methodology include the back-calculation of soil strength from a landslide inventory, sensitivity analyses regarding landslide size-pixel size relationships, and the determination of shallow landslide susceptibility for a landscape or infrastructure considering various root, water, and seismic conditions using lidar bare-earth DEMs as a topographic input. Using a distribution of inventoried landslide points and random points in non-landslide locales, the proposed methodology demonstrated reasonable correlation between regions of high landslide susceptibility and observed shallow landslides within a 150-km2 region of the Oregon Coast Range when the water-height ratio was 0.5. The method may be improved by considering spatial hydrologic conditions and geology more explicitly. 相似文献
18.
The characteristics of the seismic signals induced by landslides using a coupling of discrete element and finite difference methods 总被引：1，自引：0，他引：1
Landslide seismic signals support researchers to estimate magnitudes and locations of landslides. They can serve as a crucial data for landslide warning systems. However, the randomness of landslide locations makes the acquisition of landslide-induced seismic signals difficult and limits the number of available field data. The objectives of this study are to establish a numerical modeling approach to examine the characteristics of seismic signals induced by landslides and perform parametrical study. The two-dimensional particle flow code (PFC) and Fast Lagrangian Analysis of Continua (FLAC) are coupled to simulate the landslide process. The force and velocity data at the coupled interfaces of FLAC and PFC are transferred back and forth via a Socket I/O connection. Four locations were monitored for the induced vertical seismic signals, including velocity, acceleration, and stress histories. The signals were analyzed by Hilbert-Huang transform to obtain the time-frequency spectrograms for examining the characteristics of the signals. The particle size, wall friction, particle friction, and parallel bond of PFC input parameters were parametrically investigated. The Xiaolin landslide in 2009 was successfully simulated, and the characteristics of the seismic signals were studied and compared with the data from a broadband seismic station. These results demonstrate that terrain and transition in the movement type of a complex landslide do influence the seismic signals. A landslide with larger rock particles generates lower-frequency content seismic signals. Also, there can be approximately 40 s to escape before a large-scale landslide hits if seismic instrumentation is installed. The method proposed can be further applied for studies on many other large-scale rock avalanches to verify recorded signals and further correlate the signals with the landslide characteristics. 相似文献
19.
20.
A new approach to use AHP in landslide susceptibility mapping: a case study at Yenice (Karabuk, NW Turkey) 总被引：9，自引：4，他引：5
This study aimed to investigate the parameter effects in preparing landslide susceptibility maps with a data-driven approach and to adapt this approach to analytical hierarchy process (AHP). For this purpose, at the first stage, landslide inventory of an area located in the Western Black Sea region of Turkey covering approximately 567?km2 was prepared, and a total of 101 landslides were mapped. In order to assess the landslide susceptibility, a total of 13 parameters were considered as the input parameters: slope, aspect, plan curvature, topographical elevation, vegetation cover index, land use, distance to drainage, distance to roads, distance to structural elements, distance to ridges, stream power index, sediment transport capacity index, and wetness index. AHP was selected as the major assessment methodology since the adapted approach and AHP work in data pairs. Adapted to AHP, a similarity relation?Cbased approach, namely landslide relation indicator (LRI) for parameter selection method, was also proposed. AHP and parametric effect analyses were performed by the proposed approach, and seven landslide susceptibility maps were produced. Among these maps, the best performance was gathered from the landslide susceptibility map produced by 9 parameter combinations using area under curve (AUC) approach. For this map, the AUC value was calculated as 0.797, while the others ranged between 0.686 and 0.771. According to this map, 38.3?% of the study area was classified as having very low, 8.5?% as low, 15.0?% as moderate, 20.3?% as high, and 17.9?% as very high landslide susceptibility, respectively. Based on the overall assessments, the proposed approach in this study was concluded as objective and applicable and yielded reasonable results. 相似文献