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1.
Controlling of landsides safely and economically is a great challenge to mine operators because landslides are major geological
problems especially in open-pit mines. In this paper, a case history at Panluo open-pit mine is presented in detail to share
the experiences and lessons with mine operators. Panluo open-pit mine is located in the southwestern Fujian province of China.
It is the largest open-pit iron mine in the Fujian province and was planned in 1965 and is in full operation from 1978. In
July 1990, an earthquake of magnitude 5.3 in Taiwan Strait and big rainstorms impacted the mine slope, causing tension cracks
and rather large-scale failures, and forming a U-shaped landslide. Total potential volume was estimated to be up to 1.0 × 106 m3. This directly threatened the mine production. In order to protect the mine production and the dwellers’ safety around, a
dynamic comprehensive method was implemented including geotechnical investigations, in-situ testing and monitoring, stability
analysis, and many mitigation and preventive measures. These measures slowed down the development and further occurrence of
the landslide. The results showed that the landslides were still active, it was slowed with the control measures and moved
rapidly with rainfall and mining down. However, no catastrophic accidents occurred and the pit mining was continued till it
was closed at the elevation of 887 m in 2000. As a successful case of landslide control at an open-pit mine for 10 years,
this paper reports the controlling measures in details. These experiences of landslide control may be beneficial to other
similar mines for landslide control. 相似文献
2.
S. G. Chung P. H. Giao T. S. Nagaraj J. M. Kwag 《Marine Georesources & Geotechnology》2002,20(4):237-254
Large scale reclamation works in coastal areas of the Nakdong River plain are at various stages of progress, since early 1990's on in-situ soft marine clay deposits. These deposits are of the order of 30 to 40 m thick. A realistic rapid characterization of soft ground would ensure success of any reclamation work in this area. In order to cope with the work carried out with different agencies, it is desirable to evolve a systematic methodology. In this study, engineering properties of clays at three coastal areas, Gadukdo, Noksan and Shinho, have been generated. The analysis of data has been done within the framework of classical developments in soil mechanics. Analysis has also been made by making use of the recent developments in dealing with soft clays. The dominant factors, namely, stress, time, and environment influencing the response of clay to loading are identified. 相似文献
3.
Erodibility of low‐compaction steep‐sloped reclaimed surface mine lands in the southern Appalachian region,USA 
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下载免费PDF全文 The use of loose spoils on steep slopes for surface coal mining reclamation sites has been promoted by the US Department of Interior, Office of Surface Mining for the establishment of native forest, as prescribed by the Forest Reclamation Approach (FRA). Although low‐compaction spoils improve tree survival and growth, erodibility on steep slopes was suspected to increase. This study quantified a combined KC factor (combining the effects of the soil erodibility K factor and cover management C) for low compaction, steep‐sloped (>20°) reclaimed mine lands in the Appalachian region, USA. The combined KC factor was used because standard Unit Plot conditions required to separate these factors, per Revised Universal Soil Loss Equation (RUSLE) experimental protocols, were not followed explicitly. Three active coal mining sites in the Appalachian region of East Tennessee, each containing four replicate field plots, were monitored for rainfall and sediment yields during a 14‐month period beginning June 2009. Average cumulative erosivity for the study sites during the monitoring period was measured as 5248.9 MJ·mm·ha?1·h?1. The KC ranged between 0.001 and 0.05 t·ha·h·ha?1·MJ?1·mm?1, with the highest values occurring immediately following reclamation site construction as rills developed (June – August 2009). The KC for two study sites with about an 18–20 mm spoil D84 were above 0.01 t·ha·h·ha?1·MJ?1·mm?1 during rill development, and below 0.003 t·ha·h·ha?1·MJ?1·mm?1 after August 2009 for the post‐rill development period. The KC values for one site with a 40 mm spoil D84 were never above 0.008 t·ha·h·ha?1·MJ?1·mm?1 and also on average were lower, being more similar to the other two sites after the rill development period. Based on an initial KC factor (Ke) measured during the first few storm events, the average C factor (Ce) was estimated as 0.58 for the rill development period and 0.13 for the post‐rill development period. It appears that larger size fractions of spoils influence KC and Ce factors on low‐compaction steep slopes reclamation sites. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
4.
近十年来渤海湾围填海工程对渤海湾水交换的影响 总被引：2，自引：0，他引：2
近十年来我国海岸带地区快速城市化,对土地的需求持续高涨,导致沿海地区围海造地现象愈演愈烈,海湾纳潮海域面积持续萎缩,对海湾的水交换带来了较大压力。为此,选取我国海岸带快速城市化的典型区域——渤海湾为例,研究近十年来渤海湾海岸带城市化对渤海湾水交换的影响。基于国际流行的MIKE3水动力模型耦合粒子追踪模块,应用2000年和2010年两个典型年份的渤海湾岸线资料,分别计算了2000年和2010年渤海湾环流系统及其驱动下的水质点运移规律和变化特征。研究将渤海湾划分为8个区块,定量化研究和对比了近十年来由于渤海湾持续围填海导致的海湾水存留时间和不同区块水交换能力的变化。结果表明,随着近十年来渤海湾沿岸快速城市化产生的岸线变化,导致湾内环流涡旋增多,决定湾内水交换的流场结构发生了显著变化,导致各区块的水交换能力和平均水存留时间不仅存在较大差异,而且发生了显著的变化。与2000年相比,2010年天津港、黄骅港和曹妃甸港区海域的平均水存留时间明显增加,水交换率下降,对区域水质的改善十分不利。 相似文献
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6.
In mine soil, quantification of soil organic carbon (OC) derived recently from biomass decomposition is complicated by the presence of fossil (geogenic) C derived from coal, oil shale, or similar material in the overburden. The only reliable method for such measurement is 14C analysis (i.e. radiocarbon dating) using instrumentation such as accelerator mass spectrometry, which is too expensive for routine laboratory analysis. We tested two previously used and two new methods for recent C quantification and compared them with 14C AMS radiocarbon dating as a reference using a set of soil samples (n = 14) from Sokolov, Czech Republic: (i) 13C isotope ratio composition, (ii) cross polarization magic angle spinning 13C nuclear magnetic resonance (CPMAS 13C NMR) spectroscopy, (iii) near infrared spectroscopy (NIRS) coupled with partial least squares regression and (iv) Rock–Eval pyrolysis. Conventional methods for OC determination (dry combustion, wet dichromate oxidation, loss-on-ignition) were also compared to quantify any bias connected with their use. All the methods provided acceptable recent carbon estimates in the presence of mostly aliphatic fossil C from kerogen. However, the most accurate predictions were obtained with two approaches using Rock–Eval pyrolysis parameters as predictors, namely (i) S2 curve components and (ii) oxygen index (OI). The S2 curve approach is based on the lower thermal stability of recent vs. fossil organic matter. The OI approach corresponded well with 13C NMR spectra, which showed that samples rich in recent C were richer in carboxyl C and O-alkyl C. These two methods showed the greatest potential as routine methods for recent C quantification. 相似文献
7.
近30年来江苏省滨海湿地变化过程及其受围垦活动的影响 总被引：2，自引：0，他引：2
基于1985—2015年Landsat TM遥感影响数据,提取江苏省典型岸段滨海湿地信息,对滨海湿地类型、面积的变化过程进行研究,并分析了围垦活动对这一过程的影响。结果表明:围垦在近20年达到高峰期,连云港、盐城和南通岸段的滨海湿地在近30年间分别减少了53.15%、71.60%和71.40%。连云港岸段原生植被型湿地逐渐减少,茅草、芦苇湿地在2000年后完全消失;盐城岸段原生植被型湿地在1985—1995年间持续增加,且各植被类型比率趋于均衡,而在1995年后则转变为米草湿地占绝对优势;南通岸段湿地总面积在2000年后迅速下降,高比例的米草湿地是该岸段滨海湿地的主要特征,但到2015年几乎退化成纯光滩湿地。连云港岸段以海域围垦为主要特征,2005—2010年达到围垦高峰;盐城岸段则在1995—2000年的围垦高峰后,原生植被型湿地的围垦比率锐减,米草湿地的围垦比率增至90.51%;南通岸段以米草湿地围垦为主要特征,围垦强度在1985—2010年持续增加,2005年后米草湿地的围垦强度减小,海域围垦比例逐渐升高。 相似文献
8.
IINTRODUCTIONInthepast,thesedimenttransportisconsideredinmostengineeringproblemsbecauseofitssignificanteffectonreservoir,navigation,floo'dingcontrolandstabilityofcoastallines(Xuetal.,1992;Heetal.,1997).Inrecentyears,impactsofsedimentontheecologicalhabitatshavebeennotedbymanyenvironmentalists(Klaus,1997).Itseemsthattheconceptofsedimenthazardsorsedimentimpactsmustbeextendedandtheenvironmentalorecologicalimpactmustbeincludedinanycomprehensiveassessment.Forexample,thelarge-scaleconstructiono… 相似文献
9.
Cui-Ping Kuang Si-Yu Chen Yu Zhang Jie GuLing Deng Yi PanJing Huang 《Coastal Engineering》2012,59(1):14-27
This paper is a companion of a two-part papers on the development of a two-dimensional morphological model—CurWaC2D-Sed, based on next generation circulation solver. In this paper, the model developed in paper I is applied to the large-scale construction of near-harbor industrial zone with deep water harbor by reclamation in Caofeidian, Bohai Bay, which is a typical sandbar-lagoon bay-type tidal inlet system. Characteristics of tides, currents, waves and sediments in Caofeidian are firstly analyzed with field data from comprehensive field observations carried out in 2008. These data are then used for model calibration and validation, showing a good agreement between simulated results and field measurements for tides, currents and suspended sediments. The verified model is applied to study the effects of the construction of Caofeidian embankment and the on-going engineering scheme on hydrodynamics and sediment transports as compared with no constructions under three representative tide conditions and their combinations with normal and strong waves as well as on morphology evolution. The simulated results indicate that the present scheme leads to morphological changes in Caofeidian with acceptable rates of erosion and sedimentation. However, some attentions should be paid to erosion at offshore wharf in front of Caofedian foreland which may lead to potentially increasing landslide risks due to steep slope and sedimentation in Laogonggou creek. 相似文献
10.
农田景观空间异质性分析及遥感监测最优尺度选择——以三江平原为例 总被引：4，自引：0，他引：4
农情遥感监测需要高时间分辨率的遥感数据,目前这些数据大都为中低空间分辨率影像。在这些尺度下,像元内部往往是异质的,从而影响农情参数反演精度。因此分析和表达农田景观空间异质性和最优尺度选择对遥感农情监测质量的提高具有重要的应用价值。选取建三江农垦区四种典型农田景观为研究点,Landsat/TM NDVI为实验数据,利用实验变异函数对四种景观类型的各向空间异质性进行了分析, 而后通过变异函数模型拟合,定量分析了各个研究点的整体空间异质性,并在此基础上进行了研究区遥感监测最优尺度选择。研究表明:(1) 基于实验变异函数的结构分析方法,可定性地认识空间异质性的大小和方向,进而挖掘出其背后的自然和人为驱动因素。(2) 对实验变异函数进行拟合分析,可定量地刻画不同景观格局各自的空间异质性特性。此外,基于变异函数对空间异质性的定量表达,讨论了利用积分变程A结合Nyquist-Shannon采样定理进行最优尺度选择的方法。 相似文献