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131.
On May 2, 1993 more than 200 seismic events from an underground mine in Tyrol/Austria were recorded with short-period seismometers of a local seismic network which was introduced in the late 1980s to monitor the tectonic seismicity in Tyrol in greater detail. The cause of this series of mining-associated events has become the subject of intensive investigations — as it was associated with a subsidence affecting an area of 10.000 m2. Underground observations revealed a number of discontinuities along which the rock mass was able to move. Seismic recordings of the close-by seismic stations revealed two types of mechanisms: One mechanism seems to be associated with pure block-sliding along several discontinuities, while other signals indicate additional collapse. The consideration and combination of several seismological principles made possible the construction of a model of the mine collapse. 相似文献
132.
A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine
medium-scale experiment field for earthquake prediction and the project of monitor and prediction is given. The differences
of waveforms between mining earthquakes and natural earthquakes is discussed. The magnitude-frequency distribution of the
79 000 mining earthquakes of overM
l
1. 0 from 1984 to 1995 is summarized. Finally, taking PH and PV, the principal compressive stress components of the focal
mechanism of the mining earthquakes, as the criteria, analyses the stress background of the 12 large mining earthquakes.
Contribution No. 95C0002, Institute of Geophysics, SSB, China.
This study is sponsored by the Chinese Joint Seismological Science Foundation. 相似文献
133.
三山岛金矿海边地下开采矿山稳定性的数值模拟分析 总被引:1,自引:0,他引:1
本文用数值模拟的分析方法, 评价了三山岛金矿地下开采引起的开采效应及地表下沉盆地的变形特征。结果表明, 矿山地表是稳定的, 上部一期工程开采引起的地表最大下沉量不超过700mm, 深部开挖时不超过995mm左右;在采场充填的情况下, 地表下沉值将降低55%左右;由于矿山地表变形较小, 加之覆盖层第四纪中存在着两层总厚度8~12m的隔水粘水层, 因此不致沟通地表水与井下的直接联系而危及矿山的安全。 相似文献
134.
我国每年铁矿石供应缺口较大,并在逐年扩大,认真抓好现有矿山,充分利用现有铁矿资源,减少缺口,已势在必行。文章结合冶口 铁矿实际,提出有关措施,继续对矿山优惠政策,并鼓励矿山充分利用资源,加强矿山技术改造,坚持采矿与找矿并重,努力提高矿石的开采回收率,减少损失率,降低 相似文献
135.
136.
Analytical techniques for the estimation of mine water inflow 总被引:1,自引:0,他引:1
Summary This paper outlines various analytical techniques for mine water inflow estimation incorporating several refinements such as finite boundary conditions, linear, fracture and turbulent flow conditions to pumping wells and underground excavations. These modifications enable practical mining to be simulated and therefore, permit more accurate predictions of mine inflow quantities. Application of these techniques are given together with the scope of the application. 相似文献
137.
138.
Kot F. Unrug 《Geotechnical and Geological Engineering》1984,2(2):141-155
Summary Criteria for shaft design are described and methods of design developed. Among aspects covered in detail are: selection of shaft locations; shaft collar design and determination of collar dimensions; shaft lining design and estimation of side pressures; shaft insets and sump design. Factors considered, apart from geotechnical criteria include constraints imposed by surface structures, mineral handling and water flows. 相似文献
139.
Shi-Ning Zhou 《Geotechnical and Geological Engineering》1984,2(3):261-267
Conclusion An airflow direction of any diagonal branch in ventilation networks is a function of the resistance of each branch, but its own resistance is not a factor. It is difficult to determine the airflow of diagonal branches. But the airflow direction of diagonal branches in some complex networks can be discriminated by applying theproperties 3–8 to V-shaped, T-shaped, Y-shaped, X-shaped and double diagonal branches networks. 相似文献
140.
With increasing interest in displacement spectra and long‐period motions, it is important to check the sensitivity of both elastic and inelastic response spectra to the filtering that is often necessary to remove long period artifacts, even from many modern digital recordings. Using two records of very different character from the M=7.1, 1999 Hector Mine, California, earthquake, we find that the response spectra can be sensitive to the corner periods used in causal filtering, even for oscillator periods much less than the filter corner periods. The effect is most pronounced for inelastic response spectra, where the ratio of response spectra computed from accelerations filtered at 25 and 200 sec can be close to a factor of 2 for oscillator periods less than 5 sec. Published in 2003 by John Wiley Sons, Ltd. 相似文献