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排序方式: 共有401条查询结果,搜索用时 171 毫秒
81.
The analysis of ground vibrations induced by bench blasting at Akyol quarry and practical blasting charts 总被引:3,自引:0,他引:3
Umit Ozer Ali Kahriman Mehmet Aksoy Deniz Adiguzel Abdulkadir Karadogan 《Environmental Geology》2008,54(4):737-743
Ground vibrations arising from excavation with blasting is one of the fundamental problems in the mining industry. Therefore,
the prediction of ground vibration components plays an important role in the minimization of environmental complaints. In
this study, 582 events were recorded during limestone production at a quarry (Akyol Quarry) during a period of time. The blasting
parameters of these shots were also carefully recorded. During the statistical analysis of the collected data, three predictor
equations proposed by the United States Bureau of Mines (USBM), Ambraseys–Hendron and Langefors–Kihlstrom were used to establish
a relationship between peak particle velocity and scaled distance described by these prediction equations. As a result of
this analysis, the most powerful relationship was determined and proposed to be used in this site. And also, this equation
was used in the derivation of the practical blasting charts specific to this site as a practical way of predicting the peak
particle velocity and maximum charge amount per delay for future blasting. 相似文献
82.
郑志宏 《测绘与空间地理信息》2016,(8)
介绍了城镇土地征地拆迁管理系统的建设内容,阐述了系统建设的技术路线,描述了系统的具体设计,分析了系统的主要特点,为系统的实现提供了完整的设计方案。 相似文献
83.
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85.
A. S. Tawadrou P. D. Katsabani 《Fragblast: International Journal for Blasting and Fragmentation》2005,9(4):233-242
This paper is an application of artificial neural networks (ANNs) in the prediction of the geometry of surface blast patterns in limestone quarries. The built model uses 11 input parameters which affect the design of the pattern. These parameters are: formation dip, blasthole diameter, blasthole inclination, bench height, initiation system, specific gravity of the rock, compressive and tensile strength, Young's modulus, specific energy of the explosive and the average resulting fragmentation size. Detailed data from a previous investigation were used to train and verify the network and predict burden and spacing of a blast. The built model was used to conduct parametric studies to show the effect of blasthole diameter and bench height on pattern geometry. 相似文献
86.
Investigations were carried out at seven underground coal mines in India to characterise the responses of roof and pillars of underground workings to the vibrations induced by adjacent open-pit blasting. The roof rocks of the selected underground instrumented panels were having RMR between 36.7 to 57. Monitoring of strata behaviour was carried out before and after blasts. Arrangements were made to mount the transducers of seismographs in roof and pillars to monitor the vibration. Attempts were made to monitor the vibration simultaneously, for a blast, in the pillar and at the junction of the roof or away from the junction in the gallery. 102 sets of such vibration data were recorded in the underground mines. It was observed that the roof of underground roadways vibrated with higher peak particle velocity (PPV) compared to pillars. The amplification of vibration in the roof compared to pillars, away from the junction, was 1.02 to 2.58 times whereas at the junctions, it was 2.04 to 5.57 times. 相似文献
87.
Agne P. Rustan 《Engineering Geology》1998,49(3-4):303-313
The optimal delay time between the contour holes in rock blasting has been studied by theoretical and empirical research in Sweden, regarding ground vibrations, increase in crack frequency, radial crack length and finally overbreak (half cast factor). The model test presented in this paper concerns controlled contour blasting in tunnelling and the full-scale blasts concern tunnelling, road cutting, and dimensional stone quarrying. The results indicate that the microsequential contour blasting technique (contour holes fired in sequence and with a delay in the order of 1–2 ms) is superior to simultaneous initiation both regarding blast-induced ground vibrations and crack frequency increase in the rock mass. Both these evaluation methods reflects the conditions deeper in the remaining rock mass. Simultaneous initiation, however, is superior to micro-sequential contour blasting both regarding the half cast factor and the length of radial cracks emanating from the blastholes. These two parameters are more related to the surface conditions after blasting. The industrial applications of this new knowledge are the use of micro-sequential contour blasting when ground vibrations are of greater concern than the contour, for example, in trench blasting or quarrying in urban areas, and the use of simultaneous initiation when an even rock surface is of high priority. 相似文献
88.
节理岩体爆破数值模型及模拟研究 总被引:2,自引:1,他引:1
运用多刚体系统动力学及接触冲击理论建立了节理岩体弹塑性动态本构模型。基于DYNA-2D程序原理及其框架,利用所建模型,模拟了节理岩体的爆破过程,量化了节理岩体在爆炸载荷作用下不同时刻的应力场。 相似文献
89.
文章通过几项实例,指出在进行水压爆破施工确定药量和药包分布、布置时要充分考虑构筑物的结构与形状特点,并根据其特点对计算参数值要予以相应调整,同时还指出单位体积药量值随构筑物长宽比的不同而变化,可为类似工程施工提供参考。 相似文献
90.
直眼掏槽的爆破作用及参数计算 总被引:4,自引:2,他引:4
论述了分阶分段直眼掏槽爆破机理,提出了分阶分段直跟掏槽爆破装药量的计算依据,并给出相应的计算方法。 相似文献