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31.
张茂省 《工程地质学报》2007,15(S1):133-140
以延安市宝塔区地质灾害详细调查数据为基础,分析了影响黄土滑坡发育的因素,认为沟谷发育期、坡体地质结构、坡体形态等对滑坡的形成、分布、规模和类型具有明显的控制作用,地下水、植被对滑坡形成具有一定的影响,人类工程活动和降水的双重作用是滑坡最主要的诱发因素。  相似文献   
32.
G212线陇南段是我国滑坡最发育的地区之一,影响该段滑坡发育的因素众多,而地质构造是最主要的因素之一,本文在区域地质构造特征和滑坡分布规律研究的基础上,从断层、褶皱、岩层产状、新构造运动和地震等方面较为深入地分析了地质构造对该段滑坡的控制作用。  相似文献   
33.
文章通过某滑坡的现场调查、勘探取样及综合分析计算,着重说明了人类活动对滑坡体的稳定性影响,以及工程建设中保护生态与地质环境的重要性。  相似文献   
34.
我国长江三峡库区范围内存在严重的滑坡灾害,为了防止这些滑坡在库水位上升后复活,主要通过排水工程、支挡工程、锚固法、减重和反压等处理手段的综合运用进行防护治理。这样,在治理设计进行中就出现了很多问题,而其中主要的问题则主要包括:c、取值对设计的影响,支挡结构后滑体稳定性,支挡结构前塌岸对滑体稳定性的影响以及库区滑坡护坡工程的适用性。本文以马家沟滑坡为例,对这些问题进行了分析讨论。  相似文献   
35.
    
Accurate prediction of the hydrographs of outburst floods induced by landslide dam overtopping failure is necessary for hazard prevention and mitigation. In this study, flume model tests on the breaching of landslide dams were conducted. Unconsolidated soil materials with wide grain size distributions were used to construct the dam. The effects of different upstream inflow discharges and downstream bed soil erosion on the outburst peak discharge were investigated. Experimental results reveal that the whole hydrodynamic process of landslide dam breaching can be divided into three stages as defined by clear inflection points and peak discharges. The larger the inflow discharge, the shorter the time it takes to reach the peak discharge, and the larger the outburst flood peak discharge. The scale of the outburst floods was found to be amplified by the presence of an erodible bed located downstream of the landslide dam. This amplification decreases with the increase of upstream inflow. In addition, the results show that the existence of an erodible bed increases the density of the outburst flow, increasing its probability of transforming from a sediment flow to a debris flow.  相似文献   
36.
    
The destructiveness of impulse waves generated by landslides (IWL) originates from the wave's movement and load, wherein the impulse wave's load is the major cause of sub-aerial building damage and casualties. In this study, an experiment involving 16 groups of physical tests for the wave pressure generated by a landslide was designed, consisting of 4 sets of IWL and 4 opposite bank slope angles. A high-frequency strain system was used to measure the total pressure of the impulse wave in a water tank. The tests showed that the dynamic pressure caused by the IWL can be divided into two types: impact pressure generated by the jetflow and the pulsating pressure caused by the wave. Under the same impulse wave conditions, the maximum run-up becomes smaller as the opposite bank's slope angle increases, and the jetflow maximum impact pressure experienced by the opposite bank increases, while the maximum pulsating pressure caused by the impulse wave is slightly decreased. Different from previous studies, the spatial maximum pressure distributions of the wave generated by landslide were concluded that the position of the maximum pulsating pressure appears adjacent to the still water surface, and the overall spatial distribution pattern of maximum wave pressure is presented as an inclined   相似文献   
37.
    
Natural dams are formed when landslides are triggered by heavy rainfall during extreme weather events in the mountainous areas of Taiwan. During landslide debris movement, two processes occur simultaneously: the movement of landslide debris from a slope onto the riverbed and the erosion of the debris under the action of high-velocity river flow. When the rate of landslide deposition in a river channel is higher than the rate of landslide debris erosion by the river flow, the landslide forms a natural dam by blocking the river channel. In this study, the effects of the rates of river flow erosion and landslide deposition (termed the erosive capacity and depositional capacity, respectively) on the formation of natural dams are quantified using a physics-based approach and are tested using a scaled physical model. We define a dimensionless velocity index vde as the ratio between the depositional capacity of landslide debris (vd) and the erosive capacity of water flow (ve). The experimental test results show that a landslide dam forms when landslide debris moves at high velocity into a river channel where the river-flow velocity is low, that is, the dimensionless velocity index vde > 54. Landslide debris will not have sufficient depositional capacity to block stream flow when the dimensionless velocity index vde < 47. The depositional capacity of a landslide can be determined from the slope angle and the friction of the sliding surface, while the erosive capacity of a dam can be determined using river flow velocity and rainfall conditions. The methodology described in this paper was applied to seven landslide dams that formed in Taiwan on 8 August 2009 during Typhoon Morakot, the Tangjiashan landslide dam case, and the Yingxiu-Wolong highway K24 landslide case. The dimensionless velocity index presented in this paper can be used before a rainstorm event occurs to determine if the formation of a landslide dam is possible.  相似文献   
38.
    
An ancient landslide, situated in Deqin County, Yunnan Province, China, was used to investigate the reactivation by water infiltration. This study considers the infiltration process and landslide stability using finite-element method (FEM)-based models. The results show that the reactivation of old landslide deposit was triggered by the long-term leakage of diversion ditch before October 2012, and the reactivation was triggered again by the intense rainfall on 7–9 October 2012. The old cracks, which formed in the earlier reactivation of landslide, played a key role for the rainfall infiltration. They offered a preferential path for much more rainfall to infiltrate fast into deep soil, and caused wetting front to move down faster in landslide. The old slip zone with lower permeability was another important factor to cause the infiltrated water to accumulate and form a high pore water pressure above slip zone. Then the high pore water pressure decreased the shear strength of slip zone and triggered the reactivation of the old landslide deposit again.  相似文献   
39.
符文熹 《山地学报》2000,18(Z1):55-59
针对四川宝兴县大板桥堵江滑坡堆积体,在现场调查分析的基础上,对其作坝存在的主要工程地质问题及作坝的可行性进行了分析研究,为开展堵江滑坡作坝提供参考。  相似文献   
40.
    
Information about the long-term spatiotemporal evolution of landslides can improve our understanding of the landslide development process and can help prevent landslide disasters. This paper describes the Xiaozhuang landslide triggered by a historical earthquake and rainfall in Tianshui, Northwest China. The landslide is dominated by rotational-sliding movement. Several new failures and many fissures formed in the landslide area as a result of the 2013 Ms 6.6 Minxian earthquake and rainfall. Accordingly, field investigations, borehole drilling, geotechnical laboratory tests, and numerical calculations were conducted to study the mechanism of the landslide and to forecast its stability. A triaxial creep test of the slip soil indicates that the axial deformation of the mudstone increases with increasing water content. Numerical simulations suggest that failure is prone to occur within the deep part of the landslide under earthquake conditions. If the input seismic acceleration exceeds 0.2 g, the landslide will become unstable. Furthermore, the horizontal peak ground acceleration near the surface of the landslide is greater than that at depth. During a strong earthquake, the unstable regions are primarily located in the middle of the landslide and at its crest. When the rainfall intensity rate is 200 mm/d, the factor of safety is 1.319 and a dangerous zone appears in the lower and middle parts of the landslide.  相似文献   
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