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1.
Yanjun ZHANG Fenglong ZHANG Full QI Fuquan NI 《东北亚地学研究》2006,9(2):199-203
In view of the situation of excavation of open coal mine for the underground water disaster,we should carry out simulation studies for the numerical value of the water lowering project and improve the accuracy and the level of the water lowering project.On the basis of the hydrological geological conditions of certain open mine digging,a more reasonable seepage numerical model was built according to MODFLOW.It was simulated in advance that the process of the confined water level descending with the time,and combining with the actual observations to test the correctness of the model.The calculation showed that the results coincided well with the results of actual measurement.Based on this,different water lowering numerical simulations were built for the open coal mine digging.It could be simulated and forecast that the changes of the groundwater level in drainage process within and outside the mine pit,and it was quantitatively assessed that the possible water lowering result of the opencast water drainage process,which provide an important basis for the actual water lowering project and the possible project disposal. 相似文献
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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
4.
Investigations were carried out at three underground coal mines in India to study the response of surface structures to underground
blasting and the likelihood of damage to the structures. The structures in the vicinity of the underground blasting area were
single and multistoried residential houses. The amplitudes of vibration due to underground blasting were monitored simultaneously
on the ground surface near the foundation of the structures and on various floors of the structures. The vibrations were also
monitored near the important surface installations. It was observed that the magnitude of vibration in structures decreased
with the increase in the height of the structures. The frequency of blast vibration from underground blasting was higher than
the natural frequency of the structures. Little energy was transmitted into the structures, which caused reduction in the
vibration level in the structures. The reduction in the vibration levels was up to 45% in the houses. It indicates that the
dominant frequency of blast vibration plays an important role in persistence of vibration and its amplification or reduction
characteristics in the structures. This paper deals with the effect of the vibrations on structures/houses standing above
the blasting faces in underground workings and their potential to likely damage to the structures at different Indian geo-mining
conditions. 相似文献
5.
Summary Left in place pillars of abandoned mines are subject to weathering (e.g action of water, bacteria) that degrades their mechanical
strength and eventually leads to collapse. A simple weathering model is proposed, that is governed by two parameters: the
rate of progression of weathered front and the rate of degradation of the compressive strength with time. Both plane strain
and axisymmetric analyses are performed and closed form solutions of the variation with time of the bearing capacity of the
pillar are given. Experimental data of the tests conducted on gypsum and anhydrite specimens attacked by water are presented.
It is shown that in order to fit the experimental data a third parameter must be introduced. New closed form solutions are
given and the data are used for estimating the time to failure of abandoned gypsum mines in Northern Italy.
Authors’ address: Dr. Riccardo Castellanza, Research Assistant, Department of Structural Engineering, Milan University of
Technology (Politecnico), Piazza Leonardo da Vinci 32, 20133 Milan, Italy 相似文献
6.
南黄海灾害性地质研究 总被引:2,自引:0,他引:2
本文研完了南黄海10种灾害地质因素的性质、危害性及分布,对其进行了分类,在此基础上对本区之灾害地质进行了区划和评价。 相似文献
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大冶铁矿的开发利用在为我国的钢铁事业作出巨大贡献的同时,也给矿区的地表环境、森林资源带来了很大的破坏。矿山公园的规划实施可极大地改善矿山环境,为矿山的可持续发展提供较好的途径。 相似文献
10.