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581.
滑坡涌浪的二维有限元分析 总被引:5,自引:0,他引:5
应用二维非稳定流方程,导出滑坡涌浪的二维有了发 元模型:编写了相应的计算程序,预测了某水库边坡失稳产生的涌浪首波高度。 相似文献
582.
滑坡地下水作用研究与防治工程实践 总被引:29,自引:3,他引:29
本文从滑坡研究的现状出发, 结合滑坡防治工程的实践, 强调了滑坡地下水作用研究的重要性, 并就滑坡地下水研究所面临的主要问题对当前主要研究方向提出了建议。 相似文献
583.
In March 1989, a moderately steep slope forming sidelong ground below the B5434 Trevor to Froncysyllte Road failed after a period of exceptionally heavy rainfall and severed the highway. A long history of ground movements together with river erosion at the toe and a change in the groundwater regime within the slope created the preconditions for landslide. Site investigations characterised the ground conditions and identified the active slip surface within the compound landslide terrain. The permanent remedial measures adopted proved to be of considerable practical interest involving a bored pile anchored wall with foundations socketed into a deep sandstone foundation stratum. The anchored wall was designed to safeguard the highway and it was anticipated that deloading the slope would reduce the capacity for further movement. The wall achieved the design objective but progressive downslope movements resumed about one year after construction. They continue spasmodically to the present time with rates approaching 9 mm per year both laterally and vertically and although they affect the neighbouring areas, the highway corridor remains intact. The response of load cells attached to the ground anchors reveal two unusual patterns of increasing loads. At the eastern end of the wall, moderate load gains clearly relate to landsliding with reactivation along the existing slip surface and consequent removal of support to the wall as the ground progressively fails in a downslope direction. However, anomalous increases in loads recorded at the western end of the wall have proved more difficult to explain. They may be due either to a build up of water pressure behind the downhill portion of the wall or to localised weak ground conditions or swelling of degraded mudstones behind the wall. Monitoring of the load cells will continue in order to ensure the ongoing integrity of the highway. 相似文献
584.
滑坡稳定性分析及滑动推力的计算评价是滑坡地质灾害防治论证的重要基础,郴州市裕后街滑坡运用传递系数法计算其稳定系数可知,在天然状态下,稳定系数为1.16-1.23,饱水状态下,稳定系数为0.89-0.98,说明在降水条件下不稳定,建议采用削方减载和挡墙抗滑的综合治理方案进行防治。 相似文献
585.
Landslide inventory in a rugged forested watershed: a comparison between air-photo and field survey data 总被引:2,自引:0,他引:2
Landslide inventories are routinely compiled by means of aerial photo interpretation (API). When examining photo pairs, the forest canopy (notably in old-growth forest) hides a population of “not visible” landslides. In the present study, we attempt to estimate how important is the contribution of landslides not detectable from aerial photographs to the global mass of sediment production from mass failures on forested terrain of the Capilano basin, coastal British Columbia. API was coupled with intensive fieldwork for identification and measurement of all landslides. A 30-year framework was adopted. We show that “not visible” landslides can represent up to 85% of the total number of failures and account for 30% of the volume of debris mobilised. Such percentages display high sub-basin variability with rates of sediment production varying by one order of magnitude between two sub-basins of the study area. This is explained qualitatively by GIS-based analysis of slope frequency distributions, drainage density, and spatial distribution of surficial materials. Such observations find further support in the definitions of transport-limited and supply-limited basins. As a practical consideration to land managers, we envisage that supplementary fieldwork for landslide identification is mandatory in transport-limited systems only. Fieldwork has demonstrated that gully-related failures have a greater importance than one could expect from API. 相似文献
586.
Integration of ground-penetrating radar and microgravimetric methods to map shallow caves 总被引:1,自引:0,他引:1
Ground-penetrating radar (GPR) and microgravimetric surveys have been conducted in the southern Jura mountains of western Switzerland in order to map subsurface karstic features. The study site, La Grande Rolaz cave, is an extensive system in which many portions have been mapped. By using small station spacing and careful processing for the geophysical data, and by modeling these data with topographic information from within the cave, accurate interpretations have been achieved.The constraints on the interpreted geologic models are better when combining the geophysical methods than when using only one of the methods, despite the general limitations of two-dimensional (2D) profiling. For example, microgravimetry can complement GPR methods for accurately delineating a shallow cave section approximately 10×10 m2 in size. Conversely, GPR methods can be complementary in determining cavity depths and in verifying the presence of off-line features and numerous areas of small cavities and fractures, which may be difficult to resolve in microgravimetric data. 相似文献
587.
588.
589.
三峡库区奉节县三马山移民小区岩体的变形及其机制 总被引:8,自引:1,他引:8
三马山小区巴东组三段泥质灰岩由于岩溶溶蚀作用已全部发生了变形 ,根据变形程度的差别 ,可将变形区分为三个地带 ,即上部轻度溶蚀沉降地带 (Ⅰ ) ,中部溶蚀沉降地带 (Ⅱ )和下部沿江滑坡 (Ⅲ )。建筑设施主要分布在中部溶蚀沉降地带 ,应注意防水。下部沿江滑坡治理难度大 ,不适于移民迁建。 相似文献
590.