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George Ter-Stepanian 《Bulletin of Engineering Geology and the Environment》2002,61(3):197-205
The paper discusses the postulated suspension force, by which it is possible to explain some enigmatic phenomena observed
in different types of mass movements. This force is generated in thick suspensions as a result of friction between sinking
solid particles and static water. The suspension force is related to the seepage force but they have opposite directions.
Both forces form flow networks. Having explained the suspension force, the paper describes how this influences the movement
of material, particularly in debris flows. Enigmatic features and the mechanism of debris flows and lahars are explained by
virtue of the suspension force.
Electronic Publication 相似文献
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在竹坑水库大坝安全鉴定中,认真分析了该工程存在的主要问题,并针对大坝的结构稳定和渗流稳定作了详细的分析论证. 相似文献
5.
吴家庄水库坝址区岩洛渗漏是最主要的工程地质问题,直接影响建库规模和工程的可行性。通过对库区岩溶发育规律、特征及库区岩溶渗漏条件进行分析、计算、评价,认为水库正常高水位825m为宜。 相似文献
6.
过水堆石围堰溢:渗流规律的研究与计算 总被引:4,自引:0,他引:4
通过对混凝土板护面过水堆石围堰结构组成特性及溢流时水力状态的分析,给出了描述堆石围堰过水时堰体内外溢-渗流规律的控制方程,确定了非线性渗流表达式中各项系数的计算式及其物理意义,并建立起计算溢-渗流场的相应数学模型。在计算分析中,对垫层与排水孔的作用采用了相应的数学处理方法,使得理论分析与围堰实际工况比较接近。本文提出的公式与方法简单明了,计算结果与模型试验测值吻合良好,具有一定的实际意义。 相似文献
7.
三峡地区生态环境治理保护对策 总被引:1,自引:1,他引:0
三峡地区是全国山地灾害频发的地区之一,而由于工业的发展,沿江域镇环境污染已对长江水质构成威胁,三峡建库后,随着库区水位的抬高,长江流速变缓,排污能力减弱,易在城镇岸段和回水区形成污染带,为此,建议持续实施农业综合开发工程,扩大自然保护区,治理水土流失,改善农业生态环境,加大“长江上游防护林工程”、“长江上游水土保持工程”、“中低产田改造工程”的投资比重和治理范围,对于山地灾害防治的重点为地质灾害严 相似文献
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Infiltration and localization of preferential infiltration zones at the dam abutment are measured using radioactive tracer tests of flow in boreholes,meanwhile interconnection between boreholes and the energing water points is analysed.The theory and practice of radioactive tracer synthetic detective method are described to give methods and calculation formulae used under the condition of stable flow in single well to measure permeability coefficient and hydrostatic heads.Major single hole techniques including measurement for seepage line,velocity,rate of seepage flow and relationship of recharge of groundwater in aquifers are introduced briefly.The possibilities offered by natureal tracers are analysed,uincluding electric-conduct,pH-value and temperature of water as well as stable isotopes(D,^18O) and tritium.Furthermore,the sensibilities of this theory and methods were confirmed by detecting seepage flow field of Xinanjiang Dam. 相似文献
9.
Seepage well is an emerging Low Impact Development (LID) technology that can effectively control the storm runoff. However, its rainwater infiltration rate and storage capacity still require further enhancement. By setting a horizontal infiltration structure at the bottom of conventional rainwater seepage well (CSW), an enhanced seepage well (ESW) was proposed in this study, and its infiltration performances compared with the permeable pavement (PP) and the CSW were systemically investigated using static infiltration experiment and HYDRUS-2D simulation. The results showed that the infiltration efficiency of ESW was significantly higher than that of PP and CSW, and the process of water infiltrated through soil mainly controlled the macroscopic infiltration rate. The Nash-Sutcliff Efficient (NSE) index was used to evaluate the accuracy and reliability of the HYDRUS-2D model, and the results of NSE values greater than 0.75 (varied between 0.75 and 0.91) confirmed the applicability of HYDRUS-2D to describe correctly the hydraulic behavior of the ESW system. Simulation infiltration tests showed that the ESW performed a higher average infiltration rate and fewer total runoff volume than the CSW, indicating the effectively enhancement of the infiltration and water retention capacity of ESW, especially under heavy rainfall intensities. Additionally, the ESW system exhibited an excellent runoff-control and rainwater retention capacity in an actual rainfall scenario. 相似文献
10.
Subei Ou Lianguo Wang Peipei Wang Zhansheng Wang Jihui Huang Donglei Zhou 《矿业科学技术学报(英文版)》2013,23(2):237-244
Based on the importance of fractured rock mass seepage research, in order to analyze seepage flow characteristics of collapse column under the influence of mining, a method by embedding fractured rock mass flow solid coupling relationship into FLAC3D internal flow models is presented according to fluid–solid coupling theory and strength criterion. A calculation model of numerical analysis was established, and the influences of mining pressure and plastic damage to pore water pressure and seepage vector change rule were studied. The results show that collapse column is the main channel of confined water seepage upward. The impact is not big when the workface is away from the collapse column. But when the workface is nearing a collapse column, there will be a seepage channel on a side near the workface, in which seepage vector and head are comparatively large. With workface pushing through collapse column, the seepage channel transfers to the other side of the column. In addition, when the plastic damage area within the collapse column breaks through, a “pipeline flow” will be formed within the column, and seepage field will change remarkably and the possibility of water bursting will be greater. 相似文献