论山区高速公路运营期三坡工后评估及排查工作的必要性          下载免费PDF全文

李勇  庄生明  黄文洁 《探矿工程》2018,45(8):112-115

针对目前高速公路建设形成的“三坡”( 路基边坡、桥梁基坑边坡、隧道进出口仰坡)在运营期间发生的各类地质灾害现象,提出了高速公路“三坡”的工后评估与排查,为高速公路正常运营、地质灾害防治措施等方面提出建设性意见。  相似文献   

Geotechnical methods of reinforcement of slopes near railroads     

Vladimir D. Vereskun  Victor A. Yavna 《寒旱区科学》2015,7(5):469-474

In order to generate well-based design decisions on reinforcement of landslide slopes and road embankment slopes, a system of combined geotechnical analysis of geological conditions is suggested which includes topographic and geophysical survey, and laboratory studies of soils using infra-red spectroscopy methods. Calculations of slopes' deflected modes are carried out with taking into account elastic and elasto-plastic behavior of soil, and the presence of supporting man-made constructions. Results of the application of the system suggested may be used as criteria for the classification of landslide slopes along permanent ways according to the degree of danger when used for transportation.  相似文献   

Evaluation of factor of safety for vegetated and barren soil slopes with limit equilibrium computations     

《Geomechanics and Geoengineering》2013,8(4):254-273

Limit equilibrium method (LEM) is the most conventional and popular technique in slope stability analysis. Location of the unique failure surface and the determination of corresponding critical factor of safety (critical-FOS) of the soil slope requires a lot of trial and research. With this amount of trial and research results, we evaluate the field of factor of safety (FOS-field), which represents the critical-FOS at a point within the domain of all possible failure surfaces. Such a field can be very important for the precise judgment of the most critical-FOS of the slope and its perturbation. This paper also presents the evaluation of the FOS-field of vegetated slopes, thus providing an analytical way to examine the effect of vegetation on the soil slope stability. We evaluated the stability of vegetated and barren soil slopes under dry and fully saturated conditions. With dry and fully saturated conditions, the behaviour of slopes in most favourable and worst conditions can be simulated. Evaluation of FOS-field for various slope geometries and conditions show that the more unstable the slope becomes, the more difficult it will be to pinpoint the location of the critical failure surface with the unique least FOS. We verified the LEM codes with finite element method (FEM) and spectral element method (SEM) codes considering a sample problem from Smith and Griffiths’ book (Smith and Griffiths 2003).  相似文献   

Runoff generative process and runoff yield from arid talus mantled slopes   总被引：3，自引：0，他引：3  

A. Yair  H. Lavee 《地球表面变化过程与地形》1976,1(3):235-247

Previous works dealing with the influence of a stone cover on runoff yield showed that runoff, attributed to the sealing effect of the topsoil by raindrops impact, was negatively related to the per cent of stone cover and stone size. These works were conducted on gentle slopes (3–11·5 degree) with a per cent of stone cover generally lower than 50 per cent, and composed of gravels. The present study deals with the runoff yield of steep talus slopes (26–36 degree) whose per cent of stone cover is very high (90–100 per cent), composed of cobbles and boulders. Three stimulated rainstorms were performed at various rainfall. intensities and durations on each one of six plots representative of the North eastern sector of Sinai. Although the contiguous stony cover prevented surface sealing by raindrops impact, runoff developed quite quickly on most slopes, and reached at peak discharge, after approximately ten minutes, up to 56 per cent of the rainfall. Differences between plots, in time lag, peak discharge and other hydrological variables, could be attributed mainly to the properties of the upper stony layer, with stone size as the most influential factor. Contrary to previous works, a positive relationship, was obtained between stone size to runoff yield. The result is explained by the process of water concentration. Each cobble and boulder behaves, on a smaller scale, like a bare rocky surface and yields per unit area water amounts beyond the infiltration rate of the limited uncovered areas. For a given stony cover the effect of water concentration is quicker with the big blocks than with gravels. A series of graphs trying to relate theoretically the relative importance of sealing and water concentration processes in runoff generation, at various conditions of stone cover and stone size, is proposed. The graphs enable to reconcile the results of the present study with those of previous works.  相似文献   

基于多源数据三维可视化集成的高切坡解译     

叶润青  牛瑞卿  邓清禄  张良培  赵艳南  吴婷  江齐英 《吉林大学学报(地球科学版)》2012,42(1):161-168,176

三峡库区移民迁建工程涉及20个区(县),在城镇和公路等基础设施建设中,人工开挖而形成了大量的高切坡,其中约90%处于不稳定状态,严重威胁着库区人民生命财产安全。选择库区长江干流具有代表性的秭归-巴东库段作为研究区,采取遥感、地理信息、地质图等多源数据融合及三维可视化技术,解译了高切坡177处(总长度25.165km),提取了高切坡的位置、规模、地层、坡度、斜坡结构、工程防护措施和危害对象等信息,并分析了高切坡与地层、岩性、坡度和斜坡结构的关系。研究表明:①高切坡主要分布于城镇区及公路内侧;②碳酸盐岩、结晶岩和碎屑岩3种工程岩组中高切坡的稳定性依次降低;③香溪-泄滩亚段碎屑岩地区高切坡稳定性差,应重点防治。  相似文献   

多阶多层复杂边坡稳定性的通用上限方法     

年廷凯  刘凯  黄润秋  王亮  张彦君 《岩土力学》2016,37(3):842-849

极限分析上限方法在边坡稳定性评价中受到了广泛关注,但当前所取得的解析成果尚不能直接应用于解决任意多土层分布、多台阶的广义复杂层状边坡。基于组合对数螺线的旋转破坏机制,推导了具有任意坡面几何特征、任意多土层（含非水平土/岩层）边坡的外功率统一积分表达式及相应的虚功率方程,提出了多阶多层复杂边坡稳定性的通用极限分析上限方法;为克服积分式的复杂解析计算,引入了数值积分技术。在此基础上,结合最优化方法和强度折减技术,优化求解了复杂边坡的全局稳定性安全系数及相应的临界滑动面。通过多个典型算例的验证与对比分析,表明该方法具有较高的精度和广泛适用性。最后,针对典型多阶多层边坡实例,开展了上限法的深度拓展与应用研究,其结果为广义复杂层状边坡的稳定性评价提供了新思路。  相似文献   

基于失稳状态耗能最小原理的预应力锚索加固边坡稳定性上限解析     

赵炼恒  罗强  李亮  杨峰 《岩土力学》2013,34(2):426-432

基于岩土塑性极限分析上限理论的基本原理,考虑预应力锚索的加固效应,分析了单预应力锚索加固措施条件下边坡的稳定性特性,并由此探讨了多预应力锚索共同加固边坡的稳定性能量分析方法。结合强度折减技术,采用内点迭代方法和序列二次规划优化迭代法对锚固边坡安全系数目标函数进行了能量耗散最小化意义上的优化计算。典型算例的分析计算表明：锚索加固效应可以有效地提高边坡的稳定性,预应力锚索设置位置对边坡安全系数、临界滑裂面位置和锚索长度有显著影响。综合考虑锚索设置位置对边坡安全系数和锚索长度的影响,单锚索的最优设置位置应位于边坡中下部区域。采用多排锚索加固既可以保证边坡的安全储备,也可有效避免局部稳定性问题。  相似文献   

Ocean Rise Instability in Coastal Clay Slopes and Possible Countermeasures: A Centrifuge Modeling Study     

Ahmet Pamuk  Thomas Zimmie  Korhan Adalier  Mahadzer Mahmud 《Marine Georesources & Geotechnology》2013,31(1):58-66

Increase in saturation in natural clayey slopes along coastal zones as a result of tsunamis or storm surges may cause flow slides or failures. One of the common treatments is to increase the overall stability by soil replacement and/or re-compaction, which is often difficult to implement, expensive, and, most importantly, damages the natural vegetation. In this paper, remedial effectiveness of a relatively economical and environmentally friendly method involving insertion of geotextile strips with drainage capability into natural clayey slopes is evaluated through a series of centrifuge tests. The test results demonstrate the effectiveness of the employed technique to increase the stability of slopes and their drainage capability as well as to reduce the deformations under surcharge loadings.  相似文献   

Geotechnical evaluation of slope and ground failures during the 8 October 2005 Muzaffarabad earthquake, Pakistan   总被引：4，自引：0，他引：4  

Ömer Aydan  Yoshimi Ohta  Masanori Hamada 《Journal of Seismology》2009,13(3):399-413

A large devastating earthquake with a magnitude of 7.6 struck in Kashmir on Oct. 8, 2005. The largest city influenced by the earthquake was Muzaffarabad. Balakot town was the nearest settlement to the epicenter, and it was the most heavily damaged. The earthquake caused extensive damage to housing and structures founded on loose deposits or weathered/sheared rock masses. Furthermore, extensive slope failures occurred along Neelum and Jhelum valleys, which obstructed both river flow and roadways. In this article, failures of natural and cut slopes as well as other ground failures induced by the earthquake and their geotechnical evaluation are presented, and their implications on civil infrastructures and site selection for reconstruction and rehabilitation are discussed. It is suggested that if housing and constructions on soil slopes containing boulders as observed in Balakot and Muzaffarabad are allowed, there should be a safety zone between the slope crest and allowable construction boundary.  相似文献   

8500 a BP以来长江中游平原地区古文化遗址分布的演变   总被引：2，自引：0，他引：2  

邓辉  陈义勇  贾敬禹  莫多闻  周昆叔 《地理学报》2009,64(9):1113-1125

本研究建立了8500 a BP以来长江中游平原地区,从新石器时期至明清时期7534个古文化遗址的GIS数据库,利用ArcGIS软件,从环境考古学的角度,对不同时期古文化遗址分布的地貌类型、海拔高程、坡度特征进行了系统分析。研究结果显示,不同时代的文化遗址的空间分布特征存在显著差别：1) 新石器文化遗址主要分布在平原边缘的山前台地—岗地和高冲积平原等海拔高程适中的地区,海拔高程较低的平原中心区与海拔较高的山地则分布很少;2) 西周以后,文化遗址分布高程呈现下降趋势,从山前台地—岗地、高冲积平原向平缓的低冲积平原转移;秦汉至明清时期,文化遗址则主要分布在海拔高程更低、坡度平缓的低冲积平原和湖积—冲积平原;3) 不同时期的文化遗址空间分布模式,反映了不同生产力水平下人类活动对自然环境变化的响应特点。  相似文献