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1.
This paper deals with landslide hazards and risk analysis of Penang Island, Malaysia using Geographic Information System (GIS)
and remote sensing data. Landslide locations in the study area were identified from interpretations of aerial photographs
and field surveys. Topographical/geological data and satellite images were collected and processed using GIS and image processing
tools. There are ten landslide inducing parameters which are considered for landslide hazard analysis. These parameters are
topographic slope, aspect, curvature and distance from drainage, all derived from the topographic database; geology and distance
from lineament, derived from the geologic database; landuse from Landsat satellite images; soil from the soil database; precipitation
amount, derived from the rainfall database; and the vegetation index value from SPOT satellite images. Landslide susceptibility
was analyzed using landslide-occurrence factors employing the probability-frequency ratio model. The results of the analysis
were verified using the landslide location data and compared with the probabilistic model. The accuracy observed was 80.03%.
The qualitative landslide hazard analysis was carried out using the frequency ratio model through the map overlay analysis
in GIS environment. The accuracy of hazard map was 86.41%. Further, risk analysis was done by studying the landslide hazard
map and damageable objects at risk. This information could be used to estimate the risk to population, property and existing
infrastructure like transportation network. 相似文献
2.
Fuzzy-based method for landslide hazard assessment in active seismic zone of Himalaya 总被引：1，自引：2，他引：1
Landslides in Himalaya cause widespread damage in terms of property and human lives. It the present study, an attempt is made
to derive information on causative parameters and preparation of landslide-susceptible map using fuzzy data integration in
one of the seismically active region of Garhwal Himalaya that was recently devastated by a huge landslide. High-resolution
remotely sensed data products acquired from Indian Remote Sensing Satellite before and after the landslide event were processed
to improve interpretability and derivation of causative parameters. Spatial data sets such as lithology, rock weathering,
geomorphology, lineaments, drainage, land use, anthropogenic factor, soil type and depth, slope gradient, and slope aspect
were integrated using fuzzy gamma operator. The final map was reclassified in to five classes such as highly to lowly susceptible
classes based on cumulative cutoff. The result shows around 72% of known landslide areas including the large Uttarkashi landslide
in the high and very high susceptibility classes comprising of only 37% of the total area. The precipitation data from ground-
and satellite-based observations were compared; the precipitation threshold and the role of seismic activity were analyzed
for initiation of landslide. 相似文献
3.
浅层滑坡在我国广泛分布,但在区域范围内分布规律性较差,且具有突发性、隐蔽性和破坏性强等特点。湘西武陵山区地质条件复杂、降雨丰沛、人类工程活动强烈,突发性地质灾害频发,尤以降雨诱发的浅层滑坡为主。文章以湘西地区慈利县陈溪峪滑坡为例,开展了降雨量、基质吸力、地下水位和地表变形等的监测;结合滑坡的现场调查及监测成果,分析滑坡的形成条件和变形机理;在此基础上,考虑基质吸力对边坡稳定性的贡献,将强度折减有限元法推广到非饱和土边坡,计算得到了不同降雨工况下滑坡稳定性。结果表明:当强降雨降落到滑坡体上时,坡内基质吸力值均迅速减小,直至一定值后（9.5 kPa左右）不再变化;坡内地下水位受季节性降雨影响显著,短时强降雨引起地下水变化幅度不如长时间降雨对地下水位造成的影响大;陈溪峪滑坡的地质力学成因为蠕滑推移式土质滑坡,运动形式为沿基覆界面的浅层滑坡;短时强降雨是诱发滑坡变形的最关键因素。陈溪峪滑坡在持续降雨条件下的降雨量预警值约为280 mm,在短时强降雨条件下的降雨强度预警值约为240 mm/d。 相似文献
4.
时间域反射法用于滑坡监测的试验研究 总被引：4，自引：3，他引：1
依据时间域反射测试技术（TDR）的基本原理,提出了TDR技术在滑坡监测中的野外工作方法。为了更好地了解电缆的变化规律,进行了室内试验。结合实际应用,给出了TDR监测滑坡的野外应用实例。通过对室内模拟试验和野外应用试验数据的分析、对比,讨论了TDR监测滑坡的实际应用效果和有效性。研究结果表明,与传统的滑坡监测方法相比较,TDR用于滑坡监测的技术方法比较新颖,具有节省时间、成本低廉、定位准确等特点。由此可见,TDR用于滑坡监测,能够实现快速、实时、连续监测。 相似文献
5.
根据多种勘察手段的识别,查明厦门沪救码头附近海底地形等值线明显扭曲;码头南侧外块石与淤泥互为翻转;滑体后方淤泥可见到蜂窝状孔隙;北码头一带不连续分布有新近沉积的灰黄色淤泥且沿海岸;另外地震映像也出现绕射波相对严重等现象。本文结合地形、地层、海洋水动力条件等因素,对滑动机理进行综合分析;在不考虑海浪、地震作用下,对水下坡体采用极限平衡理论方法、后壁岸坡选择圆弧条分法进行不同的稳定性评价。研究得出:该海底滑坡形成是自然地质、人为活动和重力、海洋动力共同作用以及地层因素的综合结果。 相似文献
6.
贵阳蟠桃宫滑坡的稳定性分析和治理 总被引：1，自引：1，他引：0
蟠桃宫滑坡位于贵阳市东山南坡,其南边紧接蟠桃宫立交桥,西靠外环东路,东侧为一采石场。该滑坡东西长约70m,南北宽近60m,坡度为40°,其平面形状接近正方形, 总面积近5000m2,属岩溶地区的一个小型顺层岩质滑坡。地质上,组成该滑坡体的岩层为三叠系下统安顺组的一套浅灰色厚层状白云岩和紫红色薄层至中厚层状含铁质白云岩和泥页岩互层; 构造上,蟠桃宫滑坡为贵阳向斜东冀和东山断层南盘。整个滑体为一倾向南西的单斜构造。蟠桃宫滑坡的形成原因主要是人为修筑机场路开挖边坡,产生临空面,然后由于降水下渗进入滑体内部,尤其是经过后缘的一较大溶蚀裂隙渗透至泥页岩层使之软化成软弱夹层即泥化夹层,进而使其抗剪强度下降,导致整个滑坡体出现失稳而滑动,并引起山坡上许多民房地面及墙面开裂。根据地面地质调查,滑坡前缘及后缘等均形成纵向和横向的拉张裂隙。无疑,若不及时治理,一旦山体失稳滑动将会对人民生命及财产造成巨大的损失。本文主要涉及的问题包括对蟠桃宫滑坡产生滑动原因和力学机理的探讨,对其评价和治理方法的优选,以及治理后对滑坡的变形观测和评估等。该滑坡体的稳定性分析,主要是通过在现场地质和水文地质条件调查的基础上,对滑动带内的三个软弱夹层(即可能的滑动面)分别取扰动土样送室内作抗剪试验,并计算其相关的土力学参数。据此,在其后缘溶蚀裂隙充水的情况下计算最危险的第三个滑动面的抗滑稳定系数Fs值。计算结果表明,第三个滑动面的Fs值为1. 09,接近极限平衡状态,在外界因素影响下,很可能产生进一步的滑动。在对蟠桃宫滑坡的评价和治理上,通过对几种方法比较和论证认为,采用预应力锚索为主要的治理手段并与其它辅助手段相结合的方法,无论从经济上还是安全上都为最优的选择。通过在滑坡体的四个主要裂隙上设置9个观测点做原位变形观测证明,在使用预应力锚索治理过后整个滑坡体是稳定的。 相似文献
7.
Landslide risk assessment is often a difficult task due to the lack of temporal data on landslides and triggering events (frequency), run-out distance, landslide magnitude and vulnerability. The probability of occurrence of landslides is often very difficult to predict, as well as the expected magnitude of events, due to the limited data availability on past landslide activity. In this paper, a qualitative procedure for assessing the exposure of elements at risk is presented for an area of the Apulia region (Italy) where no temporal information on landslide occurrence is available. Given these limitations in data availability, it was not possible to produce a reliable landslide hazard map and, consequently, a risk map. The qualitative analysis was carried out using the spatial multi-criteria evaluation method in a global information system. A landslide susceptibility composite index map and four asset index maps (physical, social, economic and environmental) were generated separately through a hierarchical procedure of standardising and weighting. The four asset index maps were combined in order to obtain a qualitative weighted assets map, which, combined with the landslide susceptibility composite index map, has provided the final qualitative landslide exposure map. The resulting map represents the spatial distribution of the exposure level in the study area; this information could be used in a preliminary stage of regional planning. In order to demonstrate how such an exposure map could be used in a basic risk assessment, a quantification of the economic losses at municipal level was carried out, and the temporal probability of landslides was estimated, on the basis of the expert knowledge. Although the proposed methodology for the exposure assessment did not consider the landslide run-out and vulnerability quantification, the results obtained allow to rank the municipalities in terms of increasing exposure and risk level and, consequently, to identify the priorities for designing appropriate landslide risk mitigation plans. 相似文献
8.
位于四川省丹巴县梭坡乡的哑喀则滑坡是一大型松散土质边坡。鉴于该滑坡的严重变形和可能失稳造成严重灾害后果,所以选择进行高精度GPS监测。并且阐述了应用GPS监测滑坡时对监测点位选择、数据处理等方法。2007年至今的GPS监测结果显示主滑坡体上监测点平均位移速率达每年0.6～0.9m,表明该滑坡变形严重。结合地表裂缝和植被等地表特征,发现降雨量和坡脚大渡河的冲刷、浸泡对滑坡今后的发育趋势有着决定作用,建议加强监测做好预警预报工作。本文还特别指出在监测期内监测到的地震(2008年5月12日)和人类工程活动对滑坡造成的影响。 相似文献
9.
在每年的库水位下降期间,三峡库区的许多滑坡都出现了较大变形。为了深入研究库水下降作用下滑坡的动态变形机理,评价和预测此类滑坡的稳定性及发展趋势,本文以白水河滑坡为例,在现场地质调查和详细地质勘查的基础上,充分利用十多年监测数据,分析其变形特征、失稳机理、影响因素及稳定性,预测了其变形发展趋势。研究结果表明在水库水位下降的过程中,由于滑坡岩土体渗透性能较差,地下水来不及及时排出,滞后于水库水位的下降,滑坡受到了坡体内地下水向外的渗透动水压力作用,从而使得滑坡稳定性降低。另外库水位下降速度越快,滑坡的位移速率也越大,表现出阶跃型动态变形特征。 相似文献
10.
以山西某大型煤矿工业场地滑坡勘察与治理工程为例,分析了地下采矿对古滑坡稳定性的影响及复活机理:即采动变形降低了滑坡体土层的力学强度; 采动拉裂缝为地表水和雨水的下渗提供了渗透路径,导致滑带土发生软化; 滑坡前缘的采空移动变形对滑坡体起着牵引作用。采用工程地质测绘、钻探、物探及实时GPS监测系统等综合手段确定了滑坡周界、滑动面及滑动主方向与变形速率; 根据滑坡的空间形态、物质结构及变形特征对该滑坡体在空间上分区、剖面上分级,并据此设计了分区治理、分级支挡和留设地下抗滑煤柱等的滑坡治理方案。监测资料表明,经治理后的滑坡处于稳定状态。 相似文献
11.
以青海省南部省道红土山段滑坡为例,在分析区域地质概况和滑坡特征的基础上,对滑坡机理及影响滑坡的因素进行分析,确定滑坡滑动模式;选取合理的计算参数进行滑坡稳定性计算,根据计算结果对滑坡稳定性进行分析。得到以下结论:产生滑坡体病害的主要原因是滑坡所处区域冻土深度较大,区域冬夏温差大,地表水下渗后冻胀,次年夏初消融,这使粘性土及泥岩泥化,粘聚力降低,周而复始,滑体不断蠕动下滑。采用传递系数法对滑坡在不同工况下的稳定性进行计算,结果表明,在天然状态下滑坡浅层滑面处于蠕动变形状态,深层滑面基本稳定;在考虑暴雨和地震的条件下,滑坡处于不稳定状态。 相似文献
12.
甘肃南部坪定-化马断裂带滑坡变形特征及其防治 总被引：1，自引：0，他引：1
以坪定-化马断裂带泄流坡滑坡为例,通过野外调查和变形监测资料分析,深入剖析了断裂带滑坡变形特征和形成机理,提出了断裂带滑坡的防治方法和治理措施。断裂带滑坡一般为大型—巨型滑坡,由多个次级滑坡体组成,历史上曾多次活动。变形监测资料表明,泄流坡滑坡变形目前处于匀速蠕变阶段,呈现蠕滑-塑流拉裂-土（石）流的变形破坏特点。断裂破碎带及其现今活动为滑坡长期蠕滑变形提供了物质基础,而降雨是滑坡体失稳下滑的主要诱发因素。断裂带滑坡按岩性可归类为松散堆积层滑坡。因此,对断裂带滑坡的防治应以防为主,以治为辅,即开展滑坡变形实时监测和群测群防,辅以滑坡表面排水、坡脚压载等措施,以减缓或防止泄流坡滑坡再次形成灾害。 相似文献
13.
滑坡土体变形及其处理是滑坡治理施工中的重要问题。本文以浙江省金华市兰溪洞源村滑坡隐患治理工程为例,介绍了施工过程中出现局部不稳定问题后,施工单位与相关单位一道采取的一系列措施,包括对土体的新近变形特征与变形原因分析、应急抢险措施、应急排险效果监测、后续施工方案等内容。这些措施取得了良好的效果,为类似施工提供了借鉴。 相似文献
14.
为了能够准确有效地针对滑坡地质灾害进行监测和预报工作,给出一种新型的滑坡监测预报系统。该系统以GIS技术为基础,通过MapGIS软件形成图形文件的链接输入,实现与地理信息系统的融合。这种方法引入了滑坡空间滑动特征,可针对滑坡不同时段的特点采用多种预报模块实现对空间数据的处理,并通过VB6.0集成开发将结果还原至图形以可视化,来实现各类滑坡预报以及空间分析。将该监测预报系统应用到抚顺西露天矿地质灾害防治工作中,以GPS监测站等监测设施对抚顺西露天矿地质灾害开展的多类型的现场监测为依据, 对抚顺西露天矿地质灾害防治及预报进行分区模块处理;并以抚顺西露天矿E3200剖面滑坡为例,结合非线性回归分析及二次曲线拟合得到了X-3、X-5监测点的中短期预报数据和水平及竖直方向的速度、加速度等参量。根据竖直最大加速度为正值、竖直负向加速度小于10-5 m/d2以及水平加速度均为负值等特点,得到该滑坡基本处于匀速变形阶段及位移变化有收敛趋势的结论。 相似文献
15.
玄武岩台地区滑坡典型特征及防治对策 总被引：2，自引：1，他引：2
文章分析了江浙皖玄武岩台地区滑坡在地形地貌、地层岩性、地质构造、水文地质条件、滑坡体特征、滑动面特征、滑动多期性等方面的典型特征。由于地表水和地下水是玄武岩台地区滑坡中的主要影响因素,因此提出对该类型滑坡的防治应采用排水工程为主,并和其它防治措施相结合的方法进行治理。在滑坡治理的过程中,滑坡监测始终是滑坡防治的基础,防治的效果也需要监测工作来检验。 相似文献
16.
Javed Mallick Ram Karan Singh Mohammed A. AlAwadh Saiful Islam Roohul Abad Khan Mohamed Noor Qureshi 《Environmental Earth Sciences》2018,77(7):276
Landslides are natural geological disasters causing massive destructions and loss of lives, as well as severe damage to natural resources, so it is essential to delineate the area that probably will be affected by landslides. Landslide susceptibility mapping (LSM) is making increasing implications for GIS-based spatial analysis in combination with multi-criteria evaluation (MCE) methods. It is considered to be an effective tool to understand natural disasters related to mass movements and carry out an appropriate risk assessment. This study is based on an integrated approach of GIS and statistical modelling including fuzzy analytical hierarchy process (FAHP), weighted linear combination and MCE models. In the modelling process, eleven causative factors include slope aspect, slope, rainfall, geology, geomorphology, distance from lineament, distance from drainage networks, distance from the road, land use/land cover, soil erodibility and vegetation proportion were identified for landslide susceptibility mapping. These factors were identified based on the (1) literature review, (2) the expert knowledge, (3) field observation, (4) geophysical investigation, and (5) multivariate techniques. Initially, analytical hierarchy process linked with the fuzzy set theory is used in pairwise comparisons of LSM criteria for ranking purposes. Thereafter, fuzzy membership functions were carried out to determine the criteria weights used in the development of a landslide susceptibility map. These selected thematic maps were integrated using a weighted linear combination method to create the final landslide susceptibility map. Finally, a validation of the results was carried out using a sensitivity analysis based on receiver operator curves and an overlay method using the landslide inventory map. The study results show that the weighted overlay analysis method using the FAHP and eigenvector method is a reliable technique to map landslide susceptibility areas. The landslide susceptibility areas were classified into five categories, viz. very low susceptibility, low susceptibility, moderate susceptibility, high susceptibility, and very high susceptibility. The very high and high susceptibility zones account for 15.11% area coverage. The results are useful to get an impression of the sustainability of the watershed in terms of landsliding and therefore may help decision makers in future planning and mitigation of landslide impacts. 相似文献
17.
滑坡发生时间预报分析 总被引：7，自引：0，他引：7
王建锋 《中国地质灾害与防治学报》2003,14(2):1-8
系统论述了滑坡监测资料的整理方法：滤波和等时化。讨论了滑坡运动响应的主要组成成分。重点阐述了滑坡发生时间预报的理论基础，此基础不同于一般物理方程建立的思路，而是直接来源于观察和经验总结，并抽象为一定的数学模型。单次滑坡发生的整个过程包括孕育、如速、减速、停止等4个阶段，滑坡发生时间则指加速向减速转换的特征时间点，此点是滑坡爆发的峰值点，也是需要预报的特征时间。能够反映滑坡如此运动过程的典型数学函数是Pearl曲线，本质上此S型曲线与系统有阻尼的自由振动微分方程是一致的，也与生物群体演化的虫口方程一致，它们都共同反映了物质运动的一般规律，因此可以用来预测滑坡运动过程。直接运用一般力学报分方程描述滑坡运动过程的困难在于缺乏对滑体系统力学参数的精确把握，直接运用Logistic虫口微分方程则存在模型参数识别的困难，作者还发现某些误用灰色系统理论对Verbulst非线性方程，参数进行辩识。文末，为展示方法而不强调结果，以拥有10a监测资料的某滑坡为例，分析预报了滑坡活动过程，并进行了预测结果的数学检验。 相似文献
18.
金鸡岭滑坡在暴雨后发生明显变形,通过现场勘察、钻探、物探、深部位移监测以及水平位移监测得出初步结论。为进一步查明该滑坡成因机制,通过解译现有勘察监测资料,结合Midas-GTS软件分析不同工况下滑坡的渗流场、位移场、稳定性计算,综合评价其成因机制。结果如下：（1）物探解译得出金鸡岭滑坡为岩土混合、含水滑坡,滑动面位于T2b1泥灰岩和T2b2泥岩分界线;（2）深部位移监测揭示该滑坡为浅表层土体在发生滑移,滑动面与物探解译得出的滑动面位置一致;（3）水平位移监测表明浅表分布的后梆滑坡和潘家岭滑坡变形速率较快,变形强烈;（4）数值模拟结果显示金鸡岭滑坡在现状工况下处于基本稳定状态;在排干地下水工况下处于基本稳定状态;在暴雨工况下处于欠稳定状态,可能产生整体滑移,其上的潘家岭滑坡及后梆滑坡产生土体次级滑移。（5）金鸡岭滑坡的地形地貌、地质构造、地层岩性、为滑坡的形成和发展提供了物源和场地条件,暴雨和人类工程活动作为诱发因素,进一步加剧滑坡变形。该研究成果将为三峡库区类似滑坡的成因机制与稳定性分析提供理论依据,对后期防治措施具有重要指导意义。 相似文献
19.
求解库岸边坡岩土体的渗透系数是研究滑坡渗流场及多场演化的基础,一般通过原位试验和室内试验求得,但试验成本较高且试验位置具有一定的随机性。本文以三峡库区马家沟滑坡为例,提出一种利用地下水位动态观测资料反演滑坡岩土层渗透系数的方法。具体步骤为:（1）依据滑坡的勘察资料和水位观测数据,构建滑坡数值模型;（2）利用SPSS生成不同渗透系数正交试验组合,并将渗透系数代入数值模型中计算监测井的水位,得到不同渗透系数及其对应的模拟水位数据;（3）应用遗传算法优化的支持向量机构建坡体模拟水位与渗透系数的非线性映射关系,再通过代入实际动态监测水位值求得滑坡岩土层的渗透系数;（4）将求得的渗透系数代入数值模型,用计算的模拟水位与实际观测水位进行对比验证。研究结果表明:遗传算法优化的支持向量机具有良好的学习预测效果,能准确预测渗透系数与水位的关系。该反演方法具有高效、准确的优点,反演结果的精度满足实际应用需要。 相似文献
20.
Francesco Ponziani Claudia Pandolfo Marco Stelluti Nicola Berni Luca Brocca Tommaso Moramarco 《Landslides》2012,9(2):229-237
Rainfall thresholds represent the main tool for the Italian Civil Protection System for early warning of the threat of landslides. However, it is well-known that soil moisture conditions at the onset of a storm event also play a critical role in triggering slope failures, especially in the case of shallow landslides. This study attempts to define soil moisture (estimated by using a soil water balance model) and rainfall thresholds that can be employed for hydrogeological risk prevention by the Civil Protection Decentrate Functional Centre (CFD) located in the Umbria Region (central Italy). Two different analyses were carried out by determining rainfall and soil moisture conditions prior to widespread landslide events that occurred in the Umbria Region and that are reported in the AVI (Italian Vulnerable Areas) inventory for the period 1991?C2001. Specifically, a ??local?? analysis that considered the major landslide events of the AVI inventory and an ??areal?? analysis subdividing the Umbria Region in ten sub-areas were carried out. Comparison with rainfall thresholds used by the Umbria Region CFD was also carried out to evaluate the reliability of the current procedures employed for landslide warning. The main result of the analysis is the quantification of the decreasing linear trend between the maximum cumulated rainfall values over 24, 36 and 48?h and the soil moisture conditions prior to landslide events. This trend provides a guideline to dynamically adjust the operational rainfall thresholds used for warning. Moreover, the areal analysis, which was aimed to test the operational use of the combined soil moisture?Crainfall thresholds showed, particularly for low values of rainfall, the key role of soil moisture conditions for the triggering of landslides. On the basis of these results, the Umbria Region CFD is implementing a procedure aimed to the near real-time estimation of soil moisture conditions based on the soil water balance model developed ad hoc for the region. In fact, it was evident that a better assessment of the initial soil moisture conditions would support and improve the hydrogeological risk assessment. 相似文献