A modified approach for semi-quantitative estimation of physical vulnerability of buildings exposed to different landslide intensity scenarios   总被引：1，自引：0，他引：1  

Aditi Singh  Shilpa Pal 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2019,13(1):66-81

Landslides are the most common natural disasters in mountainous regions, being responsible for significant loss of life as well as damage to critical infrastructure and properties. As the world population grows, people tend to move to higher locations to construct buildings, thereby making structures vulnerable due to landslides. This paper discusses previous research on the vulnerability assessment of structures exposed to landslides and presents a modified semi-quantitative approach to assess the scenario-based physical vulnerability of buildings based on their resistance ability and landslide intensity. Resistance ability is determined by integrating expert knowledge-based resistance factors assigned to five primary building parameters. Landslide intensity matrix defining different intensity levels is proposed based on combinations of landslide velocity and volume. Physical vulnerability of buildings is estimated and classified as class I, II or III for scenario-based low to very high landslide intensity. Finally, the application of the model is illustrated with a case study of 71 buildings from Garhwal Himalayas, India.  相似文献   

APPLICATION OF UAVLS TO RAPID GEOLOGICAL SURVEYS          下载免费PDF全文

SHAO Yan-xiu  ZHANG Bo  ZOU Xiao-bo  WANG Ai-guo  ZHANG Fan-yu  YUAN Dao-yang  LIU Xing-wang  HE Wen-gui 《地震地质》2017,39(6):1185-1197

Three-dimensional scanning with LiDAR has been widely used in geological surveys. The LiDAR with high accuracy is promoting geoscience quantification. And it will be much more convenient, efficient and useful when combining it with the Unmanned Aerial Vehicle (UAV). This study focuses on UAV-based Laser Scanning (UAVLS)geological field mapping, taking two examples to present advantages of the UAVLS in contrast with other mapping methods. For its usage in active fault mapping, we scanned the Nanpo village site on the Zhangxian segment of the West Qinling north-edge fault. It effectively removed the effects of buildings and vegetation, and uncovered the fault trace. We measured vertical offset of 1.3m on the terrace T₁ at the Zhang river. Moreover, we also scanned landslide features at the geological hazard observatory of Lanzhou University in the loess area. The scanning data can help understand how micro-topography affects activation of loess landslides. The UAVLS is time saving in the field, only spending about half an hour to scan each site. The amount of average points per meter is about 600, which can offer topography data with resolution of centimeter. The results of this study show that the UAVLS is expected to become a common, efficient and economic mapping tool.  相似文献   

利用近震高频接收函数研究四川理县西山村滑坡体结构   总被引：2，自引：1，他引：1       下载免费PDF全文

危自根  储日升  李志伟  盛敏汉  张海江  王宝善 《地球物理学报》2017,60(10):3793-3803

远震接收函数已广泛用于反演台站下方的结构,然而由于地球的非弹性衰减作用,远震数据较难获得高频接收函数,对浅地表结构约束不足.为了克服这一问题,我们使用近震数据的高频接收函数来研究浅表速度结构,并应用于四川理县西山村滑坡体上3个宽频带地震仪记录到的近震事件.本文发展了接收函数V_P-k(V_P/V_S)叠加方法,结合接收函数H-k叠加和波形反演方法获得了台站下方滑坡体的厚度、S波速度和平均V_P/V_S比,并与钻孔得到的滑坡体厚度进行对比.结果表明,滑坡体具有小尺度的横向不均匀性,台站下方滑坡体的平均V_P/V_S比在2.4~3.1之间变化并且在底层存在78~143m·s~(-1)左右的S波低速层.本文观测到的高V_P/V_S比和底层低的S波速度结构,与电磁法获得的滑坡体底层低的电阻率和底部富水特征一致,表明滑坡体h1底界面的抗剪强度相对较弱,是潜在的滑坡危险区域.本文研究结果表明,利用近震接收函数能有效约束浅表的速度结构,进而能为滑坡灾害治理提供一定的地震学参考.  相似文献   

M5'模型树算法和无人机航拍影像在震后崩塌滑坡分析中的应用——以鲁甸M_S6.5地震为例     

王伟平  杨建思  高瑜  徐志强  姜旭东  郑钰  彭朝勇 《中国地震》2017,33(1):68-80

利用高分辨率无人机航拍影像,结合基本地质资料,分析了影响2014年8月3日鲁甸M_S6.5地震震后崩塌滑坡分布的主要因素,使用M5'模型树算法建立了崩塌滑坡密度与其影响因子间的分段线性模型,并检验了该模型的预测性能。结果表明,地震诱发的崩塌滑坡分布受断层距、岩土体结构强度、坡度、植被条件等的影响,其中,断层距、岩土体结构强度及坡度等为主要影响因素;崩塌滑坡易发生在结构破裂区及坡度为38°~50°的区域,其分布密度随断层距的增加而减小;利用M5'模型树算法建立的模型体现出崩塌滑坡分布与其影响因子间复杂的非线性关系,模型检验结果显示,理论模型与实际关联函数间的相关系数达到0.88,因此,可利用该模型预测地震诱发的崩塌滑坡的分布。  相似文献   

山区公路滑坡灾害问题及对策分析--以云南元(江)磨(黑)高速公路为例   总被引：8，自引：4，他引：4  

苏生瑞  孙芳强  吴华金  刘汝民  刘红卫 《工程地质学报》2005,13(3):340-345

随着西部公路建设的蓬勃发展,越来越多的高等级公路必须穿越山区丘陵地带,这样必然导致大量的公路滑坡的出现,危及公路的正常运行及安全。本文以云南元(江)磨(黑)高速公路为例,在分析公路沿线自然环境条件及地质构造条件等的基础上,研究公路沿线的地质灾害的特点及危害,重点研究公路沿线所发育的滑坡的分布特征、危害、形成机制及整治对策和措施。研究表明,山区公路滑坡不仅与滑坡发育的工程地质条件有关,而且与工程设计方案及公路建设过程施工方案等人为因素有关。  相似文献   

Logistic regression versus artificial neural networks: landslide susceptibility evaluation in a sample area of the Serchio River valley,Italy   总被引：6，自引：3，他引：3  

F. Falaschi  F. Giacomelli  P. R. Federici  A. Puccinelli  G. D’Amato Avanzi  A. Pochini  A. Ribolini 《Natural Hazards》2009,50(3):551-569

This article presents a multidisciplinary approach to landslide susceptibility mapping by means of logistic regression, artificial neural network, and geographic information system (GIS) techniques. The methodology applied in ranking slope instability developed through statistical models (conditional analysis and logistic regression), and neural network application, in order to better understand the relationship between the geological/geomorphological landforms and processes and landslide occurrence, and to increase the performance of landslide susceptibility models. The proposed experimental study concerns with a wide research project, promoted by the Tuscany Region Administration and APAT-Italian Geological Survey, aimed at defining the landslide hazard in the area of the Sheet 250 “Castelnuovo di Garfagnana” (1:50,000 scale). The study area is located in the middle part of the Serchio River basin and is characterized by high landslide susceptibility due to its geological, geomorphological, and climatic features, among the most severe in Italy. Terrain susceptibility to slope failure has been approached by means of indirect-quantitative statistical methods and neural network software application. Experimental results from different methods and the potentials and pitfalls of this methodological approach have been presented and discussed. Applying multivariate statistical analyses made it possible a better understanding of the phenomena and quantification of the relationship between the instability factors and landslide occurrence. In particular, the application of a multilayer neural network, equipped for supervised learning and error control, has improved the performance of the model. Finally, a first attempt to evaluate the classification efficiency of the multivariate models has been performed by means of the receiver operating characteristic (ROC) curves analysis approach.  相似文献   

Landslide Research at the British Geological Survey:Capture,Storage and Interpretation on a National and Site-Specific Scale     

Catherine PENNINGTON  Claire FOSTER  Jonathan CHAMBERS  Gareth JENKINS 《《地质学报》英文版》2009,83(5):991-999

Abstract: Landslide research at the British Geological Survey (BGS) is carried out through a number of activities, including surveying, database development and real-time monitoring of landslides. Landslide mapping across the UK has been carried out since BGS started geological mapping in 1835. Today, BGS geologists use a combination of remote sensing and ground-based investigations to survey landslides. The development of waterproof tablet computers (BGS·SIGMAmobile), with inbuilt GPS and GIS for field data capture provides an accurate and rapid mapping methodology for field surveys. Regional and national mapping of landslides is carried out in conjunction with site-specific monitoring, using terrestrial LiDAR and differential GPS technologies, which BGS has successfully developed for this application. In addition to surface monitoring, BGS is currently developing geophysical ground-imaging systems for landslide monitoring, which provide real-time information on subsurface changes prior to failure events. BGS’s mapping and monitoring activities directly feed into the BGS National Landslide Database, the most extensive source of information on landslides in Great Britain. It currently holds over 14?000 records of landslide events. By combining BGS’s corporate datasets with expert knowledge, BGS has developed a landslide hazard assessment tool, GeoSure, which provides information on the relative landslide hazard susceptibility at national scale.  相似文献   

Landslide and basin self-organized criticality in the Lushan Hot Spring area     

Chien-Yuan CHEN 《山地科学学报》2012,9(4):463-471

Defining a basin under a critical state(or a self-organized criticality) that has the potential to initiate landslides,debris flows,and subsequent sediment disasters,is a key issue for disaster prevention.The Lushan Hot Spring area in Nantou County,Taiwan,suffered serious sediment disasters after typhoons Sinlaku and Jangmi in 2008,and following Typhoon Morakot in 2009.The basin’s internal slope instability after the typhoons brought rain was examined using the landslide frequency-area distribution.The critical state indices attributed to landslide frequency-area distribution are discussed and the marginally unstable characteristics of the study area indicated.The landslides were interpreted from Spot 5 images before and after disastrous events.The results of the analysis show that the power-law landslide frequency-area curves in the basin for different rainfall-induced events tend to coincide with a single line.The temporal trend of the rainfallinduced landslide frequency-area distribution shows 1/f noise and scale invariance.A trend exists for landslide frequency-area distribution in log-log space for larger landslides controlled by the historical maximum accumulated rainfall brought by typhoons.The unstable state of the basin,including landslides,breached dams,and debris flows,are parts of the basin’s self-organizing processes.The critical state of landslide frequency-area distribution could be estimated by a critical exponent of 1.0.The distribution could be used for future estimation of the potential landslide magnitude for disaster mitigation and to identify the current state of a basin for management.  相似文献   

Contrasting rainfall generated debris flows from adjacent watersheds at Forest Falls, southern California, USA   总被引：1，自引：0，他引：1  

Douglas M. Morton  Rachel M. Alvarez  Kelly R. Ruppert  Brett Goforth 《Geomorphology》2008,96(3-4):322

Debris flows are widespread and common in many steeply sloping areas of southern California. The San Bernardino Mountains community of Forest Falls is probably subject to the most frequently documented debris flows in southern California. Debris flows at Forest Falls are generated during short-duration high-intensity rains that mobilize surface material. Except for debris flows on two consecutive days in November 1965, all the documented historic debris flows have occurred during high-intensity summer rainfall, locally referred to as ‘monsoon’ or ‘cloudburst’ rains. Velocities of the moving debris range from about 5 km/h to about 90 km/h. Velocity of a moving flow appears to be essentially a function of the water content of the flow. Low velocity debris flows are characterized by steep snouts that, when stopped, have only small amounts of water draining from the flow. In marked contrast are high-velocity debris flows whose deposits more resemble fluvial deposits. In the Forest Falls area two adjacent drainage basins, Snow Creek and Rattlesnake Creek, have considerably different histories of debris flows. Snow Creek basin, with an area about three times as large as Rattlesnake Creek basin, has a well developed debris flow channel with broad levees. Most of the debris flows in Snow Creek have greater water content and attain higher velocities than those of Rattlesnake Creek. Most debris flows are in relative equilibrium with the geometry of the channel morphology. Exceptionally high-velocity flows, however, overshoot the channel walls at particularly tight channel curves. After overshooting the channel, the flows degrade the adjacent levee surface and remove trees and structures in the immediate path, before spreading out with decreasing velocity. As the velocity decreases the clasts in the debris flows pulverize the up-slope side of the trees and often imbed clasts in them. Debris flows in Rattlesnake Creek are relatively slow moving and commonly stop in the channel. After the channel is blocked, subsequent debris flows cut a new channel upstream from the blockage that results in the deposition of new debris-flow deposits on the lower part of the fan. Shifting the location of debris flows on the Rattlesnake Creek fan tends to prevent trees from becoming mature. Dense growths of conifer seedlings sprout in the spring on the late summer debris flow deposits. This repeated process results in stands of even-aged trees whose age records the age of the debris flows.  相似文献   

A Neogene giant landslide in Tarapacá, northern Chile: A signal of instability of the westernmost Altiplano and palaeoseismicity effects     

L. Pinto  G. Hrail  S.A. Sepúlveda  P. Krop 《Geomorphology》2008,102(3-4):532-541

Giant landslides, which usually have volumes up to several tens of km³, tend to be related to mountainous reliefs such as fault scarps or thrust fronts. The western flank of the Precordillera in southern Peru and northern Chile is characterized by the presence of such mega-landslides. A good example is the Latagualla Landslide (19°15′S), composed of ~ 5.4 km³ of Miocene ignimbritic rock blocks located next to the Moquella Flexure, a structure resulting from the propagation of a west-vergent thrust blind fault that borders the Precordillera of the Central Depression. The landslide mass is very well preserved, allowing reconstitution of its movement and evolution in three main stages. The geomorphology of the landslide indicates that it preceded the incision of the present-day valleys during the late Miocene. Given the local geomorphological conditions 8–9 Ma ago (morphology, slopes and probably a high water table), large-magnitude earthquakes could have provided destabilization forces enough to cause the landslide. On the other hand, present seismic forces would not be sufficient to trigger such landslides; therefore the hazard related to them in the region is low.  相似文献