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Over the past 18 months the De Beers Consolidated Mines Ltd operations have made a concerted effort to move away from using the traditional shock tube initiating systems. These systems are being systematically replaced by the use of electronic delay detonators (EDD). Various trials were conducted in both host rock and kimberlite rock masses to improve tunnel advance as well as to optimise delay timing during trough openings [1-3]. The high cost of EDD's, when compared with traditional initiation systems, led to a number of detailed studies being conducted on the mines where EDD's were being used. These studies aimed to quantify the additional benefits when blasting with electronic detonators. The studies showed that the change was justified on the basis of increased quality control and reliability gained through the use of EDD's. However, these benefits attract other related benefits, like fragmentation control, and backbreak reductions. When compared to the shock tube initiating systems the increased development face advance and the reduction of oversize during production blasting using EDDs, compared favourably to the less costly systems. As blasting engineers gained experience and confidence in the use of the system bigger blasts were initiated in mass under-cut blasts and slot raise development, by using multiple hole firing and second delay periods between holes. In the open pit and sublevel open stope mining methods the control of the fragmentation distribution and the effect of the mass of explosive detonated during a blast is detrimental to the loading and hauling production rates and the stability of the rock mass behind the blast. With a stable rock mass the bench cutting can be executed to establish steeper overall slope angles leading to large cost savings due to a reduction in waste stripping. It is the purpose of this paper to indicate through quantification that the use of the EDDs as an initiating system improves all-round blasting performances and assists in meeting customer requirements. The customer being the ore treatment plant. 相似文献
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C. V. B. Cunningham J. Campos C. Robertson 《Fragblast: International Journal for Blasting and Fragmentation》2003,7(1):23-33
The South African mining industry first experienced en-masse use of electronic detonators in the Narrow Reef environment using AEL's Electrodet™ pre-set delay system. In recent years, programmable systems such as AEL's Smartdet™ have also established their position, and within both AEL and the mines there has been important learning around the strengths and weaknesses of these systems. In general, the fixed delay systems tend to be more easily appreciated by less-skilled work teams, and are very well suited to simple layouts, especially long, narrow blasts. However, development of programmable row controllers and series delay inserts has greatly expanded the field of usefulness of these systems while retaining most of the simplicity of use. The programmable systems are immensely flexible and therefore able to function under any condition, but require a higher level of discipline and knowledge. Much has been done to address this issue and make the systems user friendly, so the systems have converged to some extent. These systems are both valuable tools for achieving control over blasting in underground and surface applications. The choice of system is very dependent on the prevailing conditions. Accurate timing with electronic enhancements continues to show an increasing range of benefits to mining operations. There is a strong parallel with non-electronic initiation systems which helps to understand the appropriate use of the systems. 相似文献
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根据栈头公路隧道的工程特点及隧道施工的复杂性,阐述了隧道开挖的减振爆破控制技术和隧道开挖的方法,以及施工量测和振速监测技术在隧道开挖过程中的应用。 相似文献
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拟建的某洞库工程开挖断面101 m2，采用钻爆法施工修建。介绍了采用的光面爆破参数、微差爆破、间隔装药结构、复式楔形掏槽等施工工艺。 相似文献
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Thomas A. Simpson 《Environmental Geology》1989,13(2):129-135
The much increased use of explosives to move and extract rock masses in construction and mining over the past two decades has resulted in a plethora of complaints from the general public in areas of close proximity to public facilities, communication, and transportation systems. Air blasts and ground vibrations caused by explosive detonation can have desultory and damaging effects to public and private property, impose adverse effects on underground mining operations, and change the course of flow or effect the availability of surface and groundwater.Attempts to prevent damage and alleviate problems from blasting have been initiated by the federal and state governments by the promulgation of rules and regulations to prevent against vagrant and negligent blasting procedures. The Office of Surface Mining, Reclamation and Enforcement (OSMRE) provided regulations in the Federal Register on March 8, 1983, with particular reference to surface mining practices. Most of the states have adopted the OSMRE guidelines to enforce these rules and regulations.This article refers to surface mine blasting within the State of Alabama and describes some of the research efforts conducted by The University of Alabama, Department of Mineral Engineering, Tuscaloosa, Alabama, over the past several years. The article does not provide answers to the environmental problems caused by blasting but describes research activities in the past and present time frames. Although restricted to Alabama, the problem is worldwide. 相似文献
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Essaïeb Hamdi Najla Bouden Romdhane Jean du Mouza Jean Michel Le Cleac’h 《Geotechnical and Geological Engineering》2008,26(2):133-146
The theoretical explosive energy used in blasting is a common issue in many recent research works (Spathis 1999; Sanchidrian 2003). It is currently admitted that the theoretical available energy of the explosives is split into several parts during a blast:
seismic, kinetic, backbreaks, heave, heat and fragmentation energies. Concerning this last one, the energy devoted to the
breakage and to the creation of blocks within the muckpile can be separated from the microcracking energy which is devoted
to developing new and/or extending existing micro cracks within the blocks (Hamdi et al. 2001; López et al. 2002). In order to investigate these two types of energy, a first and important task is to precisely study the main parameters
characterising the two constitutive elements of the rock mass (rock matrix and discontinuity system). This should provide
useful guidelines for the choice of the blasting parameters (type of explosive, blasting pattern, etc.), in order to finally
control the comminution process. Within the frame of the EU LESS FINES research project, devoted to the control of fines production,
the methodology was developed in order to: (1) characterize the in situ rock mass, by evaluating the density, anisotropy,
interconnectivity and fractal dimension of the discontinuity system and (2) evaluate fragmentation (both micro and macro)
energy spent during the blasting operation. The methodology was applied to three production blasts performed in the Klinthagen
quarry (Sweden) allowing to estimate the part of the fragmentation energy devoted to the formation of muck pile blocks on
one side and to the muckpile blocks microcracking on the other side. 相似文献
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The literature of explosives and blasting consists of a great variety of printed materials. These materials include technical papers, books, and articles by individuals and organizations; manufacturer's product catalogs and brochures; handbooks offering guidance for the field blaster; complete encyclopedias on the subjects (and short entries in general-interest encyclopedias); government publications; proceedings of meetings of organizations devoted to the subjects; magazines specific to the subjects; articles in general circulation magazines; and other miscellaneous sources. In short, there is a multitude of literature, some well indexed for retrieval, but most not. This is a broad-brush look at the literature. 相似文献
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A Survey of Blasting Vibration Regulations 总被引：2，自引：0，他引：2
In 1998, the Blast Vibration and Seismograph Section of the International Society of Explosives Engineers formed a working group to collect and compile a list of regulations limiting ground vibrations from blasting. The goal was to locate those countries, states, provinces, and cities that have such regulations, identify which governmental body enforces them, and determine what limits on ground vibrations are imposed upon the blasting operations, and if possible, determine the basis for such regulations. In the course of this study, data was collected from over 60 jurisdictions where peak particle velocity restrictions range from non-existent to very stringent. Some of the regulations were found to be based upon standards grounded in good science, while others possess little or no technical justification. This paper will summarize the findings of the subcommittee, focusing primarily on what the limits are, which type of blasting operations must adhere to them, and to what structures they apply. The degree to which these regulations are based upon valid scientific and engineering research will be discussed. A listing of specific locations having such regulations and information about those regulations will be provided. 相似文献
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通过大量的素混凝土及钢筋混凝土结构切割爆破实践,分析归纳出其主要爆破参数计算方法和工程施工技术特点。将这些计算方法和技术要点应用于工程实践,取得了较好的切割爆破效果,达到了相应的工程目的。 相似文献
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广东省郁南县华新选矿厂拟爆破拆除的楼房,除倾倒方向外其余3个方向近距离均有保护设施或试验性保留的建筑,周围环境十分复杂。设计采取了单向倾倒∠形爆破切口,合理的爆破参数设计,可靠的爆破网路,严密的防护结构,恰当的切口支承柱切筋技术处理等一系列爆破与安全技术措施,精细化施工管理,确保了楼房向设定的方向精确爆破倒塌,而且基本不发生后坐,将建筑物的爆破塌散范围控制在安全范围内。同时,严格控制好爆破振动、爆破飞石、空气冲击波等有害效应,实现了楼房爆破拆除的成功。 相似文献