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台风暴雨条件下滑坡水文响应过程及稳定性分析 总被引:1,自引:0,他引:1
以试验数据为依据,通过数值模拟重演滑坡体对台风暴雨单峰型降雨的典型水文响应过程,得出了水文响应及稳定性的变化规律.结果表明,在降雨峰值期坡体表层快速形成饱水区,造成前缘局部孔隙水压力增大,坡脚位置地下水位抬升.边坡稳定性系数迅速下降,处于失稳状态;之后坡体的稳定性逐渐提高,仍处于不稳定状态. 相似文献
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Over the last few decades, many researchers have produced landslide susceptibility maps using different techniques including the probability method (frequency ratio), the analytical hierarchy process (AHP), bivariate, multivariate, logistics regression, fuzzy logic and artificial neural network In addition, a number of parameters such as lithology, slope, aspect, land cover, elevation, distance to stream, drainage density, distance to lineament, seismicity, and distance to road are recommended to analyze the mechanism of landslides. The data quality is a very important issue in landslide studies, and more accurate results will be achieved if the data is adequate, appropriate and drawn from a wide range of parameters. The aim of this study was to evaluate the susceptibility of the occurrence of landslides in Trabzon province, situated in north east Turkey. This was achieved using the following five methods the frequency ratio model, AHP, the statistical index (Wi), weighting factor (Wf) methods, and the logistics regression model, incorporating a Geographical Information System (GIS) and remote sensing techniques. In Trabzon province there has been an increasing occurrence of landslides triggered by rainfall. These landslides have resulted in death, significant injury, damage to property and local infrastructure and threat of further landslides continues. In order to reduce the effects of this phenomenon, it is necessary to scientifically assess the area susceptible to landslide. To achieve this, landslide susceptible areas were mapped the landslide occurrence parameters were analyzed using five different methods. The results of the five analyses were confirmed using the landslide activity map containing 50 active landslide zones. Then the methods giving more accurate results were determined. The validation process showed that the Wf method is better in prediction than the frequency ratio model, AHP, the statistical index (Wi), and logistics regression model. 相似文献
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云南瑞丽市地质灾害类型有滑坡、崩塌、泥石流和不稳定斜坡等,其中以滑坡为主、共109个.影响滑坡的因素分为自然因素、诱发因素.自然因素指滑坡的坡度、滑体岩性、滑床岩性等在自然地质条件下形成的属性.诱发因素是指引发滑坡发生的因素,主要是降雨、地震、坡脚侵蚀、坡脚开挖等影响因素.自然因素统计表明,4~14°发育的滑坡较少,15 ~40°发育的滑坡较多;滑体岩性为含砾粉土和粉质粘土;滑床岩性以片麻岩、含砾粉土、泥岩为主,砂砾粉土次之,碎石土、粉质粘土、砂岩较少.诱发因素以降雨为主,坡脚侵蚀、地震、坡脚开挖次之.最后结合影响因素给出相关的分析. 相似文献
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Ted R. Turner Steven D. Duke Brian R. Fransen Maryanne L. Reiter Andrew J. Kroll Jim W. Ward Janette L. Bach Tiffany E. Justice Robert E. Bilby 《Forest Ecology and Management》2010
Elevated landslide rates in forested landscapes can adversely impact aquatic habitat and water quality and remove and/or degrade soil resources required for forest regeneration. As a result, understanding the associations between management actions, natural factors, and landslide rates is important information needed for land managers. An unusual and powerful storm in early December, 2007, caused record flooding and thousands of landslides across southwest Washington and northwest Oregon, USA, and provided a rare opportunity to examine the effects of both natural factors and forest management practices on landslide density. Landslide inventory data were collected from both aerial photos and systematic field surveys to provide a broad survey database that was used to develop estimates of landslide density and to examine associations between landslide density, precipitation, topography, and forest stand age across a 152,000 ha forested landscape in the Willapa Hills, Washington. We estimated the probability of detecting landslides on aerial photos for six strata defined by forest stand age and a broad range of rainfall intensity, expressed as percent of the 100-year, 24-h, maximum rainfall. Key findings are that landslide detection probability decreased with increasing stand age, but was similar across rainfall intensities. The overall fraction of field-detected landslides that were not detected on 1:12,000-scale aerial photos was 39%. Very few landslides occurred in the 0–100% of 100-year rainfall category, regardless of stand age or slope gradient class. At higher rainfall intensities, significantly higher landslide densities occurred on steep slopes (>70% gradient) compared to lower gradient slopes, as expected. Above ∼150% of 100-year rainfall, the density of landslides was ∼2–3 times larger in the 0–5 and 6–10 year stand age categories than in the 11–20, 21–30, 31–40, and 41+ categories. The effect of stand age was strongest at the highest rainfall intensities. Our results demonstrate that ground-based landslide inventory data are required in order to correct for detection bias from aerial photos, develop reasonable estimates of landslide density across environmental gradients such as rainfall magnitude and topography, and make unbiased interpretations of relationships between forest management associations and landslide occurrence. 相似文献
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[目的]明确赤山斜坡土体大孔隙特征,为滑坡灾害防御提供参考.[方法]采集湖洲岛赤山斜坡土体,基于水分穿透法研究土体大孔隙特征.[结果]大孔隙尺寸范围为1.99 ~0.80 mm,居于中间尺度范围的大孔隙数量较多,大孔隙特征表现为土体表层和底层的两极分化.深度变化范围内,土体大孔隙特征会有局部突变,但总体上大孔隙数量、大孔隙尺寸、大孔隙度均随深度增加而减小.根系和有机质均是影响大孔隙特征的重要因素,但对大孔隙尺寸的影响程度更高.与有机质相比,根系与土体大孔隙特征相关性更大.[结论]局部变异并不影响大孔隙特征的整体发展规律;根系和有机质对斜坡土体大孔隙特征具有不同程度的影响. 相似文献
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基于GIS的映(秀)-日(隆)旅游公路滑坡灾害预测预报系统研究 总被引:1,自引:0,他引:1
滑坡灾害是危害最为严重的地质灾害之一,防治这种地质灾害最有效的途径是对其进行预测预报。在分析映(秀)-日(隆)旅游公路沿线滑坡地质环境和气候条件的基础上,结合ArcGIS、Matlab以及Visual C++三者的强大功能,建立了基于GIS的滑坡地质灾害预测预报系统,并阐述了数据库设计和接口设计等关键技术。系统的主要功能是实现滑坡灾害信息管理、滑坡灾害空间预测以及滑坡灾害时间预报,所得预测预报成果为公路建设和管理部门制订减灾、防灾措施等提供科学的决策依据。 相似文献
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Ali Yalcin 《CATENA》2008
The Ardesen area is prone to landslides because of the climate conditions, geologic, and geomorphologic characteristics of the region. As in previous years, in 2001 due to heavy rainfall there were many landslides resulting in damage and human casualties. There is still a great danger of further landslides in the region. Therefore, it is vitally important to prepare a landslide susceptibility map of the region. In this study, the analytical hierarchy process (AHP), the statistical index (Wi), and weighting factor (Wf) methods were used to produce and later compare three susceptibility maps. For this purpose, thematic layers including landslide inventory, lithology-weathering, slope, aspect, land cover, distance to stream, drainage density, and distance to road were used. In this study area, 98% of landslides occurred in highly or completely weathered units. Lithology-weathering, land cover, and slope data layers were found to be important factors in the study area. To confirm the practicality of the three susceptibility maps were compared with a landslide activity map containing 16 active landslide zones. The outcome was that the active landslide zones do not completely fit into the high and very high susceptibility classes. But 81.3% of these landslide zones fall into the high and very high susceptibility zones of the AHP method while this is 62.5% in the case of Wi method, and 68.8% with the Wf method. In spite of the results obtained in this study, the development of a susceptibility map is usually determined by the needs and available resources. The results showed that the AHP method gave a more realistic picture of the actual distribution of landslide susceptibility, than the Wi and Wf methods. 相似文献
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