福建平潭虎潮山滑坡成因机理分析与评价   总被引：3，自引：0，他引：3  

秦刚  姚环  林燕滨 《中国地质灾害与防治学报》2006,17(3):10-13

虎潮山滑坡位于平宏公路12k 704~12k 884段北侧山坡体上,是平潭海岛通往陆地的唯一公路通道。论文通过定性的工程地质分析和定量计算评价了虎潮山坡体稳定性的变化趋势,提出改建公路超挖深切坡脚和持续长时间强降雨导致的孔隙水压力作用是边坡发生滑动破坏的主要因素。  相似文献   

Modeling of rainfall-triggered shallow landslide   总被引：5，自引：3，他引：5  

Tung-Lin Tsai  Jinn-Chuang Yang 《Environmental Geology》2006,50(4):525-534

By integrating hydrological modeling with the infinite slope stability analysis, a rainfall-triggered shallow landslide model was developed by Iverson (Water Resour Res 36:1897-1910, 2000). In Iverson’s model, the infiltration capacity is assumed to be equivalent to the saturated hydraulic conductivity for finding pressure heads analytically. However, for general infiltration process, the infiltration capacity should vary with time during the period of rain, and the infiltration rate is significantly related to the variable infiltration capacity. To avoid the unrealistically high pressure heads, Iverson employed the beta-line correction by specifying that the simulated pressure heads cannot exceed those given by the beta line. In this study, the suitability of constant infiltration capacity together with the beta-line correction for hydrological modeling and landslide modeling of hillslope subjected to a rainfall is examined. By amending the boundary condition at ground surface of hillslope in Iverson’s model, the modified Iverson’s model with considering general infiltration process is developed to conduct this examination. The results show that the unrealistically high pressure heads from Iverson’s model occur due to the overestimation of infiltration rate induced from the assumption that the infiltration capacity is identical to the saturated hydraulic conductivity. Considering with the general infiltration process, the modified Iverson’s model gives acceptable results. In addition, even though the beta-line correction is applied, the Iverson’s model still produces greater simulated pressure heads and overestimates soil failure potential as compared with the modified Iverson’s model. Therefore, for assessing rainfall-triggered shallow landslide, the use of constant infiltration capacity together with the beta-line correction needs to be replaced by the consideration of general infiltration process.  相似文献   

小岩头滑坡稳定性分析     

张赣敏  艾桂根 《华东地质学院学报》2006,29(4):357-360

小岩头滑坡位于贵州省威宁县二(连浩特)河(口)高速公路K255 010~K255 240里程右侧,属一个大型古滑坡,发育于二叠系上统峨嵋山组玄武岩(P2β)地层中。在高速公路施工中对路堑进行深挖削坡,可能导致古滑坡中部、线路右侧斜坡失稳破坏,发生滑坡。因此,滑坡稳定性评价是重大工程地质问题之一。根据大量勘察试验资料,系统地揭示了滑坡的特征,分析了滑坡形成的控制因素、成因和形成机制,建立了滑坡体稳定性计算模型,利用反演计算法进行稳定性分析与评价,认为两滑体均处于滑动失稳状态。建议对滑坡体进行处理,采用排水、支挡、减压等措施进行整治。  相似文献   

Site Investigation for the Effects of Vegetation on Ground Stability     

John R. Greenwood  Joanne E. Norris  Jo Wint 《Geotechnical and Geological Engineering》2006,24(3):467-481

The procedure for geotechnical site investigation is well established but little attention is currently given to investigating the potential of vegetation to assist with ground stability. This paper describes how routine investigation procedures may be adapted to consider the effects of the vegetation. It is recommended that the major part of the vegetation investigation is carried out, at relatively low cost, during the preliminary (desk) study phase of the investigation when there is maximum flexibility to take account of findings in the proposed design and construction. The techniques available for investigation of the effects of vegetation are reviewed and references provided for further consideration. As for general geotechnical investigation work, it is important that a balance of effort is maintained in the vegetation investigation between (a) site characterisation (defining and identifying the existing and proposed vegetation to suit the site and ground conditions), (b) testing (in-situ and laboratory testing of the vegetation and root systems to provide design parameters) and (c) modelling (to analyse the vegetation effects).  相似文献   

二维地震观测系统合理性的论证方法     

SUN Xiao-jie LI Chao-lin WANG Li-bin REN Ri-chun LI Hai-yan ZHUANG Yi-ming LIU Ying-xin SUN Ke .Daqing Petroleum Institute  Daqing  Heilongjiang  China .Coalfield Geological  Geophysical Exploration Company of Jilin Province  Changchun  China .Coal Field Geology Bureun of Jilin Province  Changchun  China 《吉林大学学报(地球科学版)》2006,(Z2)

已知勘查区深度范围前提下,最大炮检X和道间距ΔX,不可以太大也不可以太小,施工前能够计算出它的允许值范围。  相似文献   

SVD和DCT提取特征向量的方法在人脸识别中的比较   总被引：5，自引：1，他引：5  

卢健  王晖 《武汉大学学报(信息科学版)》2005,30(2):118-122

采用奇异值分解和2D离散余弦变换两种方法得到的特征，分别在嵌入式隐马尔可夫模型的人脸识别中进行比较．得出奇异值分解比2D离散余弦变换在识别率上和时间复杂度上部较差的结果。通过对结果进行分析得出，虽然奇异值分解有很多优良的特性．但是在模式识别中仅使用奇异值分解来提取特征并不是很好的方法。  相似文献   

乌江下游沿岸滑坡发育特征     

白云峰 《中国地质灾害与防治学报》2005,16(2):43-46

乌江是黔东北和渝东南少数民族地区与外界联系的一条水上黄金通道。担负了流域内80％以上的客货运输量。满足了沿岸2000多万人民生产和生活必需品运输的需要。乌江下游的彭水县城至涪陵市是乌江进入长江航运的咽喉要道，沿岸广泛分布和频繁发生的滑坡严重地威胁着航运的安全。通过现场调查发现，在长约150km范围内，两岸共发育各类滑坡28个，发育线模数为0．187个／km。沿岸滑坡发育形式主要为岩石顺层滑坡和风化堆积层滑坡。沿岸滑坡具有群发性的分布特征，与地层岩性和河谷岸坡类型等密切相关。岩石顺层滑坡主要集中分布在顺向岸坡软、硬岩层相间地段。风化堆积层滑坡则主要分布在软岩地层及其风化物堆积的岸坡地段。构造变动、河流的切蚀作用及人类活动是滑坡发育形成的主要原因，暴雨和长时间降雨是滑坡发生的重要诱发因素。目前，多数滑坡处于稳定状态，少数滑坡受降雨及江水涨落的影响而处于周期性蠕动变形状态。三峡水库蓄水后，部分滑坡有复活的可能。  相似文献   

单一滑面边坡的非稳定蠕变模型分析   总被引：3，自引：0，他引：3  

何峰  王来贵  刘向峰 《中国地质灾害与防治学报》2005,16(4):29-31

对单一滑面边坡的非稳定蠕变分析是边坡稳定性研究的基础。文中对岩质边坡单一滑面的流变变形机制进行了分析，提出了一种能较好反映这一变形机制的非稳定蠕变模型。特别是描述单一滑面边坡的非稳定蠕变破坏阶段，并对其稳定性进行了讨论。结合一些工程实例进行了对比验证，为滑坡灾害的预测和防治提供依据。  相似文献   

条带开采煤柱稳定性的试验模拟与数值分析——以山东省济宁市太平煤矿为例   总被引：1，自引：0，他引：1  

杨伟峰夏筱红  黄治灿刘汪威 魏永军 《中国煤田地质》2005,17(2):29-31,55

以山东省济宁市太平煤矿为例，采用煤柱模拟试验和数值分析手段，对薄基岩条带开采时所留设煤柱的应力应变状态、煤柱强度结构及煤柱长期稳定性进行了深入的分析与研究，揭示了煤柱稳定性及煤柱应力分布与条采尺寸、采出率、覆岩特征的相互关系，进行了条带煤柱的稳定性评价，为工程实践提供了理论依据。  相似文献   

水库下游河流再造床过程中的河岸侵蚀   总被引：3，自引：0，他引：3       下载免费PDF全文

张春燕  陈立  张俊勇  王志国 《水科学进展》2005,16(3):356-360

根据实测河道地形资料,分析了水库下游河床演变中的河岸侵蚀现象,包括不同横向边界约束条件、不同床沙组成和不同河型河段的河岸侵蚀的特征及规律。结果表明:①水库下游均会有河岸侵蚀发生,但初期一般以下切为主,后期以展宽为主。②对于横向边界约束较强的河段,河岸侵蚀相对较弱;相反,则河岸坍塌严重,河岸侵蚀强烈;③对不同的河床组成和边滩组成的河段:河床较粗特别是形成抗冲粗化层,且边滩组成较细的河段,河岸侵蚀现象非常剧烈;河床组成较细的河段,如果边滩抗冲性较强,则河岸侵蚀现象相对较弱,如果滩地组成较细、容易坍塌,河岸侵蚀也会较强;④不同的河型有着不同的河岸侵蚀现象。分汊河段以主汊为主;游荡段的游荡特性在初期受到抑制;弯曲河段的撇弯切滩现象较普遍。  相似文献