You are all aware that mining is a major economic sector of any country. Line drilling a method of overbreak control which uses a series of closely spaced holes that are not charged. Prevention and control measures different measures were adapted to control geological overbreak, in particular, by preventing secondaryoverbreak. To simplify the work, rock blasting is the easiest way.
Airblast and ground vibration are discussed along with methods for evaluation and control. However, there are other issues related to bench stability, and future blast performance based on the amount of overbreak occurring during a blasting operation. The idea is to minimize or eliminate overbreak from the primary blast. It was used as a handbook for the fhwa course of the above title. Blast damage control reduces scaling time and dilution, allows easier. Ed, the handbook of chemistry and physic, fortythird edition. Rock blasting fundamentals a pdh online course for. This book was updated and launched in 2015 to include the newest information available in the explosives and blasting industry. A fuzzy rulebased approach to address uncertainty in risk.
Limiting of overbreak with good perimeter blasting cautious blasting practices such as presplitting and smooth blasting are well known e. A complete copy of rock blasting and overbreak control is available free of charge in adobe acrobat pdf format by following the internet link. Reflections on the functionality of presplit blasting for wall control in surface mining rock fragmentation by blasting, fragblast 10, proc. The use of vent holes or vent pits may also be necessary. This section only covers the basic concepts of rock blasting. Stemming is a material that is put inside of a blast hole to help prevent gases from escaping. Only the most naively optimistic amongst us would claim that the end of the road has been reached and that the subject has matured into a fully developed applied science. The oregon department of transportation is providing the short course rock blasting and overbreak control on october 3rd through 5th at their flanders office in portland, oregon. The primary objectives in rock blasting are to optimize blast performance and ensure the.
Loading density the weight of explosives per metre of. When an explosive charge is detonated, chemical reaction occur which, very rapidly changes the solid or liquid explosive. Anfo ammonium nitrate mixed with fuel oil is the most common product. Excessive amounts of overbreak on a rock face can cause several issues. Report date t i t l e and subtitle december 1991 rock blasting and overbreak control 6. In order to achieve the optimum blasting results, it is of paramount importance. Following are the techniques of controlled blasting. The detailed requirements for design of rock cuts provided in fhwa hi99007 rock slopes reference manual munfakh, et al. Pound for pound anfo is a more effective explosive. Strict control of the environmental impacts of blasting operations needs to be completely in line with the regulatory limits. This class is designed for engineering geologists, geotechnical engineers, and construction inspectors. Explosives are energy, and the efficient use of this energy is a major factor in keeping rock blasting costs under control. A guide for highway engineers and blasting practitioners working with highway applications.
The original version of this book was written in 1983 for the federal highway administration. This reference may be obtained free of charge in adobe acrobat pdf format through the fhwa at the following. Rock blasting consists of drilling holes in the rock at depths, in diameters, and at spacing so that the anfo ammonium nitrate fertilizer and fuel oil diesel fuel can fracture the rock in a controlled manner. Federal highway administration national highway institute u. Chapter 19 blast design introduction this chapter is an introduction to blasting techniques based primarily on the explosives and blasting procedures manual dick et al. Ruby pipeline, llc plans to blast only in the areas where the rock cannot be economically excavated by conventional means. Rock blasting and overbreak control drilling nature. Understanding the connection between blasting and highwall. Much of the information in the module is derived from the surface mining control and reclamation act of 1977 smcra. Zongxian zhang, in rock fracture and blasting, 2016. Controlling the adverse effects of blasting this module addresses the control of offsite impacts that result from blasting, namely. Common question during mining and tunneling operations is whether overbreak has been caused by blasting practice or poor rock mass quality. Participants at the conclusion of the class will be able to.
Toward this aim, a blast design software tool was completed in collaboration with the colorado school of mines and hustrulid mining services. The topic is covered in more detail in the fhwa manual rock blasting and overbreak control. Pdf rock blasting and control overbreak yuri garcia. Predicting overbreak blocks is a valid way to protect constructors, safeties in the process of tunnel excavation. Chapter 12 rock cut design washington state department. Conventional drifting or tunneling by drilling and blasting method requires a much higher specific charge than ordinary production blasting such as bench blasting. The 5th edition of rock blasting and overbreak control by dr. While stemming is typically put in the top of a blast hole, it can also be.
University of rizona mining and geological engineering rock excavation mne 415 515. This handbook is specifically designed as a guide to highway engineers and blasting practitioners working with highway applications. Several examples are given to help simplify calculations with some stepbystep procedures. Causes, impact and control of overbreak in underground excavations article pdf available in tunnelling and underground space technology 201. The newly developed light sectioning method has been used to investigate some of the causes and costs of overbreak and underbreak. Tempat belajar semua engineer teknik sipil indonesia anda bebas untuk mendownload ebook, software dan tutorial tentang teknik sipil anda juga bisa mendapatkan info terbaru tentang lowongan kerja dan ilmu teknik sipil all about civil engineering. Line drilling, trim cushion blasting, smooth contour or perimeter blasting, presplitting, selecting and employing various parameters of blast design, using modern technology, precise and accurate timing delays, muffle blasting at critical and congested areas. Pdf causes, impact and control of overbreak in underground. University of rizona mining and geological engineering. Control and reclamation act of 1977, upon which their state surface coalmine. Blasting will take place along the ruby pipeline project rightofway. Investigations at the aquamilpa hydroelectric project in mexico have shown decreased overbreak and increased underbreak as a result of increased rock quality and decreased explosive energy. In addition, for the development of blasting plans for rock cut excavation, the fhwa manual entitled rock blasting and overbreak control,fhwahi92001 konya and walter, 1991 shall be used. Pdf drill and blast system is used in hard rock excavation due to its economics and adaptability to changing rock mass conditions.
In this paper, a prediction method of the overbreak blocks in tunnels is developed in the frame of the wavelet neural network of geological statistics models. In such operations, flyrock control is of high importance especially due to safety issues and the damages it may cause to infrastructures, properties as well as the people who live within and around the blasting site. Initiations and timing effects as well as patterns are also discussed. Stemming for blast holes academy blastingacademy blasting. Measurement of blast damage office of surface mining. Techniques of controlled blasting linkedin slideshare. Engineered blasting agents, not dynamite account for 99% of explosive material used. Observations should be aimed at providing insight into. Tagged blasting, blasting techniques, controlled blasting techniques, mining leave a comment. Rock blasting and control overbreak fhwa us department of. Types of blasting primary type of blasting will be for ditch excavation. It is anticipated that this may occur anywhere along the rightofway. Advantages emuline is a continuous length of emulsion packaged in tough.
In this video anthony konya of explains stemming and stemming calculations. Emuline is a continuous length of emulsion packaged in tough film cartridges with an. There is a tendency to consider mine tunnels as temporary access ways, but how many mines are using tunnels that are thirty or. A new measure of explosive energy, the perimeter powder factor. Image from rock blasting and overbreak control, fhwa, 1992. It was used as a handbook for the fhwa courses of the above title. The handbook is specifically designed as a guide to highway engineers and blasting practitioners working with highway applications. The typical method of drifting is to drill and blast. Many of the figures and specification concepts originated from the rock blasting and overbreak control manual. The damage results in overbreak or rock that was not designed to be removed, loose rock to be scaled, and permanent damage to the remaining perimeter.
Predictions of overbreak blocks in tunnels based on the. In classification and development in grade control blasting for surface mines fragblast, trevor little, director and principal consultant. Modification of blasting procedures should include limiting the size and frequency of blasts to limit the production of noxious fumes, and stripping of the overburden prior to blasting and excavating the shot rock immediately after blasting to allow the venting of gases. Drilling and blasting an overview sciencedirect topics. For example, the specific charge at tunneling is 310 times higher than at bench blasting, depending on borehole deviation, tight holes, lift of the. Mechanism of rock breakage while release of explosives energy upon detonation and other relevant points are discussed below. The economic analysis of the use of explosives is an important part of blasting operations in mining and construction.
Highenergy explosives enhance fragmentation, which ultimately produces a positive effect on production. Blasting is an economical method to break rock, but t he consequence of blasting is damage to the perimeter of the opening. Rock blasting and overbreak control free ebook download as pdf file. Rock and mineral identification for engineers 1991. The project aim was to provide industry and mine research institutions with detailed information on perimetercontrolled blasting and blast damage models that support perimeter control design. Balasubramanian centre for advanced studies in earth science university of mysore mysore6 2. In portal area, overbreak was minimized by preexcavation treatment of rockmass through fore. Geometrical parameters of structural plane are first obtained by field survey. The most important of these is the increased worker and equipment exposure to potential rock fall hazards. Rock blasting and overbreak control fhwahi92001 a slideshow presentation has been provided for the participant to.
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