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By Louis A. Sandbak

Drift excavation by boom-type roadheaders in the San Manuel and Kalamazoo sulfide copper ore bodies has been successfully demonstrated. Geomechanical rock classification in conjunction with detailed geologic mapping has been necessary to assess roadheader performance, and to predict advance rates in the varied rock classes in the San Manuel block caving mine. Rapid excavation and less fractured ground are obvious advantages of roadheader drift excavation over conventional drill and blast techniques. The geomechanical system of Engineers International (1984) can be an effective roadheader performance and ground support tool.

Jan 1, 1985

By Herbert H. Einstein, Edward C. Tse, David B. Ashley

INTRODUCTION Decision-making in the design and construction of underground facilities must be made under conditions of varying geologic uncertainty, uncertainty which can have a major cost impact if not properly regarded. Of the two approaches for dealing with this variability, preparing for the "worst" anticipated conditions and optimizing design and construction in-situ, preparing for the "worst" conditions is the more if not solely conventionally practiced method in the United States. While the conventional approach is recognized at times to be extremely overconservative, it will remain preferred until a more adaptable method is shown to be economically superior. This paper presents research aimed at providing just such answers as to when and if an adaptable tunnel design and construction approach is more cost effective than a non-adaptable one. To fully understand the characteristics of this choice between adaptable and conventional tunneling alternatives a summary discussion of adaptable methods is presented. An acknowledgement of the importance of geologic and other factor uncertainties in making this decision leads to the adoption of decision analysis as a quantitative methodology for formalizing the problem. Exercising this methodology on three prototypical tunneling scenarios--urban deep, urban shallow, and transmountain--allows an isolation and ranking of the most crucial factors in making the basic approach decision. One scenario, a transmountain highway tunnel, is carried further through a detailed probabilistic analysis to show under what conditions of varying uncertainty adaptable approaches possess economic advantages.

Jan 1, 1979

By A. C. Lyons

The presentation describes the history, preliminary report, site investigation, including examination of old records, design of tunnel including choice of levels, alternative linings and working sites, the preliminary contract involving shaft sinking on the site of the Tower Block; design modifications, the main contract, including shaft sinking, ground treatment, compressed air installation, machine tunnelling, tunnelling enlargements for chambers, waterproofing and equipment.

Jan 1, 1981

By Carmel Bofinger, Maureen E. Hassall, David Cliff, Eric Stemn

e Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

By F. Chavan

1. Introduction The new Cleuson-Dixence development project in the Valais region of the Swiss Alps, involves the construction of a new link between the Grande-Dixence dam (still world recordholder with a height of 300 m) and a power house on the banks of the Rhone consisting of approximately 20 km tunnels and shafts, and involving a fall of about 1900 m. This 1200 MW project will replace an existing 900 MW structure built in the 1960s, no longer considered efficient. The new project comprises a head race drift about 15.8 km long, a surge tank, an inclined cascade shaft 4,2 km long, and an underground power station. The work for lots C and D (head race drift from Tortin to Tracouet, surge tank, six adits ans the complete inclined shaft) was awarded to our group (Prader, Locher, SELL, Losinger, Evéquoz, Dénériaz, Imboden and Bouygues). The geological conditions are: Lower part of the shaft (300 m) : sedimentary - sandstone and soft tertiary sandstone. Middle and upper part (2600 m) : metamorphic - upper and lower carboniferous, interrupted by triasic chipping. The horizontal section (7 km) consists of mica

Jan 1, 1995

By A. Tsouchlaraki

The physical relief is a variable of utmost significance in the course of the analysis, evaluation, design and management of the visual environment. In this sense, there are cases where it would be desirable to isolate the relief from the other elements making up the visual environment and to investigate its visual value separately. Such cases include the technical works that cause major and permanent alterations to the relief, as well as the works, of which the spatial arrangement depends on the morphology of the ground. Slopes, distances, hypsometric difference values, viewsheds are elements of the relief that affect the visual value of a landscape, but also the ability of a particular landscape to accept and absorb new activities. This paper describes an evaluation and prediction model of the visual value of the landforms. A questionnaire survey takes place in order to investigate the public preference, using a sample of 221 persons in the broader area of Athens. The means used to demonstrate the various forms of reliefs are 32 perspective digital relief images. Following this and in order to investigate the elements of the relief that affect its visual value, 20 quantitative indices were developed and examined so as to select the best ones. Linear prediction models of the visual value were investigated from the previous elements, through a regression process. The applications of the proposed model in physical environment planning are many, such as the prediction of visual impact by arranging works that alter the relief of a region, as it happens in mining, metallurgical and waste disposal sites.

Jan 1, 2005

By Gerald G. Griswold, Allan G. Provost

"To Sink or Not to Sink"; this play on the Bard's words sums up the considerations and problems that face the owner on every potential shaft sinking project. The growing demand for access into the earth is pressing construction into new areas and to greater depths. The following discussion will entertain some of the effects of these new and unknown aspects upon the approach to designing and sinking of deep shafts. We will also look at the current shortages of equipment, materials and skilled manpower, and their effect upon the planning and sinking of shafts. Particular emphasis will be placed upon equipment selection, and we will discuss how economics, while always a prime consideration, is now, more than ever, both an incentive and a detriment to the industry. FUTURE CONSIDERATIONS Shaft construction is assuming ever increasing importance both in mining and civil endeavors. The rapid depletion of near surface mineral reserves is requiring the mining industry to look deeper into the earth for new sources. These greater depths increase the exposure to unfavorable geological conditions; heavier ground, high water pressures, and high temperature. South African gold mines have now reached depths of 12, 000 feet, where the rock temperature is 1380 and water bursts from the fissures. In North America depths to 7, 500 feet have been sunk, but deep shafts are still generally considered to be those of

Jan 1, 1974

By Karin Bäppler

Hydropower produces almost two-thirds of the world’s renewable electricity generation and delivers a major contribution on the ambition of the Paris Agreement and Sustainable Development Goals (SDG) with a range of benefits to society and environment. These include clean and flexible generation and storage in addition to reduced dependence on fossil fuels and avoidance of pollutants. The Limberg III PSP is one of the European projects that addresses the implementation of the UN SDGs. The challenge of the project is the construction of a 770 m long pressure shaft to be excavated with a TBM at an inclination of 42°.

Jun 13, 2023

By J. Seiter

Mining has always been among the most hazardous of occupations, and with the increasing demand for coal and minerals, safety in mines assumes even greater importance. Worldwide, underground miners are being exposed to noise and respirable dust hazards associated with roof bolt drilling. These hazards are now being understood to cause irreparable damage to the health of miners. The objective of this research was to discover if a Polycrystalline Diamond Cutter (PDC) drill bit generates less respirable dust and hazardous noise than a competing Tungsten Carbide (WC) bit, in dry vacuum drilling. In order to control the drill parameters the drilling tests have been conducted in a laboratory setting. The results were met by determining the quantities of dust and noise generated using each drill bit and analyzing those levels by using monitoring devices and software to collect the data. This paper includes information on experiment setup, equipment used, drilling parameters, and data collected. The test results suggest that there are noticeable trends that the PDC bits produce less dust than WC bits but more testing is needed to substantiate these trends.

Feb 23, 2014

By Ronald B. Gabitzsch, Norbert P. Hanke

During 1982, record advances have been achieved in the excavation of vertical shafts with a V-Mole (a vertical shaft boring machine). The V-Mole, supplied by Wirth GmbH in Erkelenz, West Germany, has been used in West German coal mines since the early seventies, mainly for the construction of internal shafts. In 1981, it was brought into the United States for the construction of a series of ventilation shafts with depths varying between 512 m (1680 ft.) and 622 m (2040 ft.) excavated to 7.0 m (23 ft.) diameter. These shafts were needed for the development of coal mines for Jim Walter Resources, Inc. in Brookwood, Alabama. After a description of the mechanized shaft excavation system with the V-Mole, the conditions and parameters, such as ground, shaft dimensions, and linings are discussed. These factors are important considerations for a technically and economically feasible utilization of the V-Mole. In addition, the advantages and disadvantages of using the V-Mole technology in comparison to other shaft construction methods are evaluated.

Jan 1, 1983

By Heinz Kettling

Labor costs, which have rapidly increased in the industrial countries for several years, have forced the mining industry to develop new methods and cost saving systems. Also, because mining is basic to meeting the increasing requirements for raw materials, the mining industry is guaranteed a key position in cost cutting efforts. Although this report aims to describe major recent developments in the Federal Republic of Germany, it is restricted to a limited number of them in view of the wide variety of current innovations. The most important mining activities in West Germany are concentrated in the coal mines on the Rhine, Ruhr and Saar, in the lignite open-cast mines west of Cologne and in the potash and salt mining region in Lower Saxony and Hesse. This report will only discuss developments in the underground coal mines and the potash and salt mines, and focuses on projects of Salzgitter Maschinen and Anlagen AG (SMAG). HYDRAULIC DRILLS Drilling strata of varying strength One special difficulty faced in European coal mines is the varying of compressive strength of strata that occurs even over a few meters. The strata associated with the coal measures ranges from hard and tough sandstone or conglomerate to very soft carboniferous shale. It is often difficult to use continuous miners or roadheaders so that drifting by blasting still predominates. But the varying compressive strengths of the strata makes it difficult to choose the best method to drill the rock. For example, it is best to penetrate hard sandstone or conglomerate with heavy percussion drills. The soft carboniferous shale on the other hand, should be penetrated by high speed rotary drilling to obtain optimum performance.

Jan 1, 1979

By François Martin, Roland Plassart, François Laigle

"MOTIVATION The storage of nuclear waste gives rise to a lot of innovative issues for underground space technologies. The nuclear activity of waste generates temperature effects on both the lining and the surrounding rock mass. In order to avoid these unfavorable effects, the number of waste containers is controlled in the gallery section. The galleries section has consequently ranged from a diameter of 4 to 6 meters. However, in the case of intermediate-level nuclear waste, due to the lower temperature, the number of containers in a cross section of a gallery is assumed to be safely increased. Despite technical difficulties, a large diameter gallery (typically 12m excavated) seems to be more cost effective. This paper demonstrate the feasibility of such a gallery in the specific context of CIGEO (French Geological Repository Project for nuclear waste), located in the Bure area in the north-eastern of France. The geology of Bure at the project’s depth (about 520 meters) consists in a quite homogeneous layer of Callovo-Oxfordian argillites (COx argillites). With such an overburden, this rock is known to have a high plastic behavior with significant time-dependent effects. These mechanical properties require complex behavior laws in computational modeling used for the design of underground facilities.EXPERIENCE OF LARGE DIAMETER GALLERIES In order to identify some specificities in the design of such openings, a research has been run on existing galleries of large diameter (more than 10 meters), like the tunnel of Chamoise, Lötschberg, Tartaiguille or Saint-Martin-La-Porte. Two of these representative examples are detailed hereafter. Tunnel of Chamoise (French Jura) In spite of a lighter overburden (400m versus 520m), an anisotropic initial stress state and a variable rate of carbonates, the highway tunnel of Chamoise is quite similar to the planned gallery for intermediate-level nuclear waste, with a geology very close to the CIGEO’s one in some sections. Because the northern tube encountered difficulties during the excavation a few years before (several over-excavations and spalling, especially in the bench), the excavation of the southern tube has been carried out in two steps, but with a high bench and a small curved invert (Figure 1). The design of the immediate support consists in long bolts and a shotcrete layer. The concrete lining is about 50cm thick."

Jan 1, 2016

By Michael S. Robinson, Serge Moalli

Construction of the CSO Retention - Treatment Tunnel, Segment 1 in Dearborn, Michigan includes excavation for an overflow Structure with a minimum inside diameter of 15.24 m (finished). The excavation extends downward through overburden soil including a 15.2 m thick zone of potentially weak clay. This paper presents the subsurface data for the clay and a geotechnical analysis thereof, together with predictions of the behavior of the planned 15.54 m inside diameter open end caisson as it is sunk through this potentially weak zone. In a companion paper, the writers will compare the behavior observed with that predicted.

Jan 1, 1995

By John A. Shuster

Case histories are reported for several soft ground shafts ranging from 6' to 40' in diameter and 50' to 230' in overburden depth for which ground freezing was employed to provide temporary ground support and groundwater control during shaft sinking through the overburden. Cases reported emphasize dealing with difficult site and ground conditions such as working within existing buildings, through very soft, running and bouldery soils, in the presence of substantial lateral groundwater flows, and into salt dome deposits requiring special considerations. Construction procedures, schedule, and relative costs are discussed for each case.

Jan 1, 1985

By A. Fiszer

One of the major problems with deep Polish hard coal mines are deformations of close-to-wall galleries since they are necessary and must he kept open for emergency situations and are largely responsible for work disturbances. In order to ensure safe and effective working operations, it is necessary to often rebuild galleries which, apart from the inevitable stoppage of operations, is greatly disadvantageous for the operation of a mine. The largest problems with maintaining the galleries open occur in Lower Silesian Coal Field mines where sometimes it is necessary to reconstruct the galleries several times [(Fig. 1)]. In light of what has been said above, the aim of this article is to present the reader with methods and ways of determining deformations occurring in close-to-wall galleries. Squeezing or convergence of headings is only a portion of the entire process of ground movement caused by ground disturbance due to workings. The term "squeezing of headings" is to be understood as a shortening of the distance between a point set on the roof of a heading and the corresponding one on the floor. It is very important to know the rules governing the process of squeezing in a particular mining system since it affords possibilities to define changes of the process and its parameters at any moment for a given system. This is of utmost importance because convergence of a heading is one of the most significant manifestations of ground pressure which has already been proved by studies performed by Everling (1). On the basis of those studies it has been observed that there exists an almost linear relation between the rate of convergence and loading [(Fig. 2)]. This, in turn, means that the deformations of the already exploited portion of heading are proportional to the pressure changes.

Jan 1, 1982

By J. R. Walls

Mining is one of world's oldest industries. Its rich history continues into modern times. The Waste Isolation Pilot Plant (WIPP) located in southeastern New Mexico is writing the next chapter in mining history. In fact, WIPP technology is the key to closure of the nuclear cycle with the disposal of nuclear waste in a deep geological repository. It might seem odd that the age-old institution of mining would be linked to the problem of nuclear waste disposal. In fact, the nuclear industry would not exist without mining. Uranium ore is mined from either underground or surface mines as the initial step in harnessing the magnificent resource of nuclear energy.

Jan 1, 1996

By Djamhur Sule, Husaini

Almost 90 % of phosphate in Indonesia is consumed for natural and manufactured fertilizers, while the rest is used in chemical industries. The consumption of phosphate always increases each year, while Indonesian phosphate production is almost constant at around 75,000 tons annually, except the production in 1988 was 165,000 tons. Due to the limited amount of domestic production, the imported phosphate is increasing each year. Phosphate trading in Indonesia is unique. Some of the domestic production is exported to Taiwan, while phosphate from USA, Morocco, Jordan and Nauru is imported. Indonesian phosphate includes guano phosphate, caving phosphate and small amount of marine phosphate sediment. Problems with Indonesian phosphate include: scattered deposits in difficult locations and a relatively small amount of reserves. Exploitation of phosphate deposits for domestic purpose has a good prospect, mainly because of the rapidly increasing phosphate demand as natural fertilizer or as a raw material for manufacturing fertilizer to support an agricultural sector.

Jan 1, 1993

By J. Alton Burks, Robert R. Stein

This paper focuses on the noise exposure levels of miners employed on longwall production faces. Along with the increased production from longwall units has come the potential for greater noise exposures. Typical noise levels are given for the various noise sources that are present on modern longwall faces. Exposure times have typically increased since the introduction of longwall technology in this country. Representative exposure times and patterns are analyzed. Possible solutions are presented for generalized cases. Engineering controls developed by the Bureau of Mines are explained and their potential effectiveness is calculated for the cases presented. The role of hearing protectors in an overall hearing conservation program is also investigated. Recent research performed by the Bureau suggests that the actual performance level of muff -type protectors may be less than the manufacturers ratings under certain circumstances. The use of muff- type protectors is discussed and analyzed with respect to their use on longwall operations.

Jan 1, 1992

By B. Lin, C. Tang, Z. Chen

Earthquakes, underground impact pressures and rock bursts all produce acoustic emissions. The rate of these emissions can be used to describe rock instability. In this study, it was found that acoustic-emission rates obtained by simulating a twin sample (rock-rock) model could be used to indicate the acoustic-emission-rate characteristics during rock instability. A computer simulation and two case studies support this conclusion.

Jan 1, 1997

By D. D. Snyder, J. D. Bode, F. T. King

INTRODUCTION Only in recent years have the environmental hazards associated with mining and tunneling operations been fully acknowledged and determined remedial action undertaken. The nature of these excavation operations leads to a wide diversity of hazards spanning mechanical, electrical, chemical, environmental, and physiological. The most insidious of these are unquestionably the environmental ones which have the greatest long-term effect and are the most difficult to pinpoint and monitor. It is the atmospheric contaminants that lead to a significantly greater illness and mortality rate among miners. Dust is the most prevalent, hence most important of the atmospheric contaminants. Respirable particles lead to diseases characteristic of many mining operations: coal workers pneumoconiosis, asbestiosis, silicosis, talcosis, anthrocosis, etc. But toxic and suffocating gases can be equally insidious and the most innocuous pollutant, methane, leads to the most imminently disastrous results of all - explosion and fire. This means that truly effective monitoring of the environmental hazards in tunneling cannot be limited to a few simple standard check measurements. It must include the most precise measurements we can make for specific, documented hazards and even for factors, such as noise and heat stress, not immediately obvious as hazards. The Federal Metal and Nonmetallic Mine Safety Act and more recent Occupational Safety and Health Administration standards are clearly designed to match such effective monitoring. We must, therefore, consider not only presently available monitoring instruments and those currently under develop-

Jan 1, 1997