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Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

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Science china(Technological sciences) 2005年第Z1期48卷 65-80页

作者： LIU Bingshan1, LI Shihai1, ZHANG Lei1,2.& WANG Jianguo31. institute of Mechanics, chinese academy of sciences, Beijing 100080,{2. 2. Graduate School, chinese academy of sciences, Beijing 100060,{2. 3. Tropical Marine Science institute, National University of Singapore, 10 Kent Ridge Crescent, Singapore 1192.0 institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100060 China Tropical Marine Science institute National University of Singapore 10 Kent Ridge Crescent Singapore 119260 Singapore

When the sliding mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form higher artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding forces of the sliding mass, thus lowering the safety factor, and inducing landslide disasters. In this paper, a landslide experimental apparatus is designed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying pressure is a crucial parameter affecting the stability of the slope; (2. when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3) the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying rock and soil on the upper 30% area. In this article, a discrete element method simulation is used to investigate the influence of cleft water pressure and shearing strength on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a high level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

DEBRIS FLOW DISASTER AND ITS MITIGATION COUNTERMEASURES IN THE CONSTRUCTION OF THE mountain AREAS IN THE WESTERN china

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Natural Disaster Reduction in china 2003年第3期 2-9页

作者： Wei Fangqiang, Xie Hong, Zhong Dunlun, Cui Peng and Hu Kaiheng (institute of mountain {2. and environment, chinese academy of sciences and Ministry of Water Conservancy, chengdu 610041, china)

The economy and construction of cities/towns in the mountain areas will grow rapidly along with deepening of the western development program, during which debris flow disaster will be more serious. How to solve this problem and mitigate the debris flow disaster is an important task. In this paper, the distribution, harm and developing tendency of debris flow were analyzed. After discussing prevention projects, rebuilding and expanding of old cities/towns and traffic construction that will meet debris flow problem, integrative mitigation countermeasures, such as controlling debris flow by civil engineering, improving drainage area environment by biologic project, forecast of risk zones and disaster situation, were put forward.

关键词： western development mountain area town debris flow mitigation countermeasure

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泥石流沟床比降的几点讨论

水土保持学报 1999年第S1期11卷 51-55页

作者：李泳中国科学院成都山地灾害与环境研究所成都610041

沟床比降是影响泥石流发生和运动的基本参数，但通常在水力学和工程学中应用的比降计算公式在形式上是不确定的，也没有直观的几何意义。以积分形式重新定义比降发现影响泥石流运动的应是有效比降，它的改变在泥石流的发生和运动中起着... 详细信息

沟床比降是影响泥石流发生和运动的基本参数，但通常在水力学和工程学中应用的比降计算公式在形式上是不确定的，也没有直观的几何意义。以积分形式重新定义比降发现影响泥石流运动的应是有效比降，它的改变在泥石流的发生和运动中起着重要作用，泥石流的阵性特征可能是这种作用的一个表现；最后讨论了由比降参数γ决定的泥石流速度估算公式γ的分布将是一个有趣的问题。

关键词：泥石流比降势能速度估算

Plant Pb Contents in Elevation Zones of the Changbai mountain National Nature Reserve, china

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Pedosphere 2007年第2期17卷 229-234页

作者： BAI Jun-Hong CUI Bao-Shan DENG Wei WANG Qing-Gai DING Qiu-Yi State Key Lab of Water environment Simulation School of Environment Beijng Normal University 19 Xinjiekouwai Road Haidian District Beijing 100101 （China）. institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610051 （China） Appraisal Center of environment and Engineering State Environment Protection Administration of China Beijing 100012 （China）

Typical plants and soils of four elevation zones, mountain tundra （Zone A）, Betula ermanii forest （Zone B）, mountain dark coniferous forest （Zone C）, and mountain coniferous and broad-leaf forest （Zone D）, along the vertical gradient of the northern mountain slope of the Changbai mountain National Nature Reserve, Jilin Province, china, were sampled to study the relationship between plant and soil Pb, and to compare the Pb levels in typical plant types within the same elevation zone. The Pb contents in the soil and plant samples were measured by using a flame atomic absorption spectrophotometer. The results showed that the average plant Pb contents of the four plant elevation zones were lower than the average worldwide level, except for Zone B. Compared with the average level in china or the average worldwide level, the soil Pb levels of the four plant zones were higher, with Zones D and B having the lowest and highest averages, respectively. Plant Pb levels fluctuated from the upper to the lower zones, in a pattern of low-high-low-high, which was the same as that of the soils in the four zones. Furthermore, plant Pb was closely related to soil Pb. Depending on the plant species and plant parts, large differences were found in the Pb levels of typical plants within each zone. In Zone A, Vaccinium uliginosum and Rhododendron redowskianum had higher Pb levels than the other plants. In Zone C, the Pb levels in the branches of both plant species were higher than those in the leaves, which was contrary to Zone D. In Zone B, the Pb levels in the plant parts varied greatly with plant species.

关键词： elevation zone plant Pb Pb uptake soil Pb typical plants

A New Treatment of Depression for Drainage Network Extraction Based on DEM

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Journal of mountain Science 2009年第4期6卷 311-319页

作者： WANG Yan PENG Hong CUI Peng ZHANG Wanshun QIAO Fei CHEN Cai'er School of Resource and environmental Science Wuhan University Wuhan 430079 China College of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072 China institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 China chinese academy of {2.al sciences Beijing 100012 China

Depressions in landscapes function as buffers for water and sediment. A landscape with depressions has less runoff, less erosion and more sedimentation than that without depressions. Sinks in digital elevation models （DEMs） can be considered the real features that represent depressions in actual landscapes or spurious features that result from errors in DEM creation. In many hydrological and erosion models, all sinks are considered as spurious features and, as a result, these models do not deal with the sinks that represent real depressions. Consequently, the surface runoff and erosion are overestimated due to removing the depressions. Aiming at this problem, this paper presents a new method, which deal with the sinks that represent real depressions. The drainage network is extracted without changing the original DEM. The method includes four steps： detecting pits, detecting depressions, merging depressions, and extracting drainage network. Because the elevations of grid cells are not changed, the method can also avoid producing new fiat areas, which are always produced by the conventional filling methods. The proposed method was applied to the Xihanshui River basin, the upper reach of the Jialingjiang River basin, china, to automatically extract the drainage network based on DEM. The extracted drainage network agrees well with the reality and can be used for further hydrologic analysis and erosion estimation.

关键词： Drainage network extraction Depression processing Digital elevation model Wooden barrel effect Xihanshui River basin.

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高切坡超前支护桩与坡体共同作用分析

山地学报 2006年第5期24卷 574-579页

作者：何思明中国科学院水利部成都山地灾害与环境研究所四川成都610041

针对高切坡施工常常导致边坡失稳破坏,诱发滑坡发生的现象,提出采用超前支护桩整治不稳定高切坡的设计理论。采用解藕方法研究了超前支护桩与开挖坡体之间的相互作用机制,其中高切坡开挖面采用弹性理论分析；超前支护桩采用可以考虑桩... 详细信息

针对高切坡施工常常导致边坡失稳破坏,诱发滑坡发生的现象,提出采用超前支护桩整治不稳定高切坡的设计理论。采用解藕方法研究了超前支护桩与开挖坡体之间的相互作用机制,其中高切坡开挖面采用弹性理论分析；超前支护桩采用可以考虑桩侧向土体屈服的弹塑性理论进行桩的内力理论解,根据两者之间荷载变形关系建立联系求解,为高切坡超前支护桩的设计提供依据。结果表明：桩土相互作用力大于常规主动土压力,与边坡开挖量、开挖高度、支护桩的刚度以及土体性质等因素密切相关。

关键词：超前支护桩高切坡相互作用机制

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中国山地生态安全屏障保护与建设

山地学报 2008年第1期26卷 2-11页

作者：钟祥浩中国科学院水利部成都山地灾害与环境研究所四川成都610041

文章论述了构建中国山地生态安全屏障的重要性,提出了以大陆地势变化三级阶梯为基础的山地生态安全屏障宏观构架,遵循地形为主导因素,并结合水热因素的分异,对中国山地生态安全屏障进行了分区,共分出3个大区,40个区和66个亚区。在此基础... 详细信息

文章论述了构建中国山地生态安全屏障的重要性,提出了以大陆地势变化三级阶梯为基础的山地生态安全屏障宏观构架,遵循地形为主导因素,并结合水热因素的分异,对中国山地生态安全屏障进行了分区,共分出3个大区,40个区和66个亚区。在此基础上,提出了如何开展以亚区为单元的山地生态安全屏障保护与建设的途径及其应着重研究的科学问题,同时,提出开展山地生态安全屏障体系构建及其保护与建设研究可以作为促进山地学科发展切入点的看法。

关键词：中国山地山地生态安全屏障保障与建设

DEBRIS FLOW & ITS DISCIPLINARY NATURE

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Natural Disaster Reduction in china 2002年第4期 8-12页

作者： Liu Xilin (institute of mountain {2. and environment, chinese academy of sciences, chengdu 610041, china) Mo Duowen (Department of Urban and environmental sciences, Peking University, Beijing 100871, china)

Due to the inadequacy of knowledge on nature of debris flow, definitions of the subject differ. A review of the study on debris flow in the past 70 years, which was represented by over 50 teaching materials of sciences/monographs in this area, may lead to the conclusion that geomorphology is the parent subject of debris flow study. With the growth of the disciplinary growing point, a new cross disciplinary subject hazard geomorphology or geomorphic catastrophology has come into being, of which debris flow is a subject matter. The article expects to stimulate more discussion and debates on debris flow so as to boost the development of its study.

关键词： geomorphology debris flow geomorphic hazard

Ecological Engineering for South to North Water Transfer Project in china:A Review of Conservation Buffer System Approach

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Ecological Engineering for South to North Water Transfer Pro...