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介绍了锦屏一级水电站右岸导流洞的工程地质概况及施工期安全监测成果,对围岩及边坡的变形、应力规律及特征进行了深入的分析,分析结果表明,隧道围岩及边坡处于稳定状态。 相似文献
874.
蓝小公路边坡防护中的预应力锚索技术 总被引:1,自引:0,他引:1
预应力锚索作为高危边坡加固的一种有效措施,在公路建设事业中得到了广泛的应用。本文结合蓝小公路边坡防治实例,介绍了锚索的作用机理及优越性、锚索的设计计算、锚索施工等一系列问题,对同类工程具有重要的参考意义。 相似文献
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876.
模糊综合评判方法在四川某公路深挖路堑边坡稳定性分析中的应用 总被引:2,自引:0,他引:2
应用模糊综合评判方法分析研究四川某公路深挖路堑边坡的稳定性 ,研究表明边坡整体及部分块体在边坡开挖后均处于基本稳定状态 ,为边坡的治理提供了依据。 相似文献
877.
Seismic stability analysis of reinforced slopes 总被引:4,自引:0,他引:4
In this paper, the seismic stability of slopes reinforced with geosynthetics is analysed within the framework of the pseudo-static approach. Calculations are conducted by applying the kinematic theorem of limit analysis. Different failure modes are considered, and for each analytical expressions are derived that enable one to readily calculate the reinforcement force required to prevent failure and the yield acceleration of slopes subjected to earthquake loading. Several results are presented in order to illustrate the influence of seismic forces on slope stability. Moreover, a suitable procedure based on the assessment of earthquake-induced permanent displacement is proposed for the design of reinforced slopes in seismically active areas. 相似文献
878.
Salah Sadek Isam Kaysi Mounia Bedran 《International Journal of Applied Earth Observation and Geoinformation》2000,2(3-4)
Highway route layout design typically relies on aerial photographs, topographic maps and geologic maps. In this paper, a GIS platform, which incorporates the main digital data needed for evaluating route layouts, is used in a computer-based approach for highway layout assessment. Possible layouts are evaluated based on two sets of criteria. First, traditional evaluation criteria focussing on geometric design factors and impact on man-made features are considered. Next, the developed assessment framework builds on the GIS platform to generate specific environmental and geotechnical criteria for route layout evaluation. The developed approach integrates highway design, slope stability, and traffic noise modeling packages and specifically written codes with the GIS packages ARC/INFO and ArcView. A prototypical application of the assessment framework for a proposed highway south of the city of Beirut, Lebanon is presented. The results demonstrate the potential of the developed approach in incorporating new evaluation criteria at the route layout design stage and in automating the route layout assessment procedure. 相似文献
879.
S. K. Chaulya R. S. Singh M. K. Chakraborty B. K. Srivastava 《Geotechnical and Geological Engineering》2000,18(3):193-207
An integrated study on biological stabilisation of a dump slope has indicated that biological reclamation with grass and tree species should be considered for long term stability of this coal mine dump in India. The grasses have greater soil binding capacity and help to control soil erosion and improve dump stability. Native grasses such as Bamboo (Dendrocalmus strictus) and Kashi (Saccharum spontaneum) are the important constituents of grass species which can stabilise the dump slopes. Field observation of growth performance of grasses have indicated that mean grass height, root depth and below-ground root biomass are 185 cm (±68), 45 cm (±5) and 467 g m–2 (±170), respectively after three years of grass growth on Mudidih overburden dump slope in India. The growth performance of tree species, namely Sisum (Dalbergia sisoo) and Subabool (Leucena lecocephala), in terms of height, diameter increment, below-ground biomass and root depth have shown mean values of 219 cm (±94), 48 mm (±6), 4.0 kg m–2 (±1.5) and 1 m (±0.1), respectively. This acts as biological fertility which helps in root proliferation and enhancement of dump stability. From the numerical modelling it is suggested that roots of these grass and tree species have significantly enhanced the factor of safety of dump from 1.4 to 1.8 and therefore have a positive role in maintaining long term stability. 相似文献
880.
琼东南盆地高精度层序地层学研究 总被引:40,自引:2,他引:38
运用当代层序地层学的原理和方法, 综合分析了地震、测井、岩心等资料, 发现琼东南盆地经历了早期裂陷和晚期坳陷两大发育历程, 相应划分出TejasA和TejasB两个超层序组; 与盆地非海相、海相过渡相、生长断层、缓坡和被动大陆边缘背景演化阶段相匹配, 形成了5个超层序.以不整合及其与之可以对比的整合为三级层序边界, 识别出19个层序, 含5 7个体系域、5 4个以上准层序组、196个以上准层序.在盆地的不同演化阶段, 沉积层序的不同点主要在于低水位体系域包含的沉积体系不同.在恢复古地理环境的基础上, 提炼出有关沉积层序模式.根据可容纳空间分析, 编制了本区海平面升降曲线, 发现陵水中期、梅山早期和莺歌海早期三次大的海泛与全球变化完全合拍.在纵向上, 海进体系域至密集段生烃潜力最强, 空间上以外陆架-大陆坡最好, 其次为滨沼或海陆过渡相.指出了陆架坡折附近的低水位楔和斜坡扇是值得注意的隐蔽圈闭勘探目标. 相似文献