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By Sharanappa Yalal, Rakesh Kumar Khali

"Himalayan geology poses the most challenging ground conditions almost anywhere in the world, one of the reasons thereof is their evolution as the youngest mountain chains. They are demonstratively rising faster than any mountain elsewhere. The composition is also younger, and consequently less well consolidated than the other older fold belts. This is consistent with the fact that they constitute one of the most active of the plate margin zones rising at a rate that is almost double the Andes, which is in turn three times that of the Alps. Thus, stress conditions (Magnitude and variations) can potentially be more extreme and adverse on a Himalayan tunneling project. Tunnel excavation under the Himalayan Mountains will pose significantly more challenges than an equal length and equal cover drive almost anywhere in the world. These in-depth-tunneling difficulties through high mountainous terrains have posed major challenges for application of traditional drill and blast (D&B) and NATM methods. Handling such adverse geology at any depth is always problematic and generally leads, if not adequately foreseen, to the significant tunneling delays. The author wants to highlight the challenges faced and on the spot solutions adopted while executing most prestigious 273Km long Udhampur –Srinagar- Baramula Rail Link Project (USBRL) in the Himalayas in the state of Jammu & Kashmir, India. The main focus of the paper is on main stretch of USBRL Project i.e. T-80 (India’s 2nd longest railway tunnel & 3rd longest in Asia) where the team of the author has recently completed a 11.2 Km long tunnel and where the train track has gone operational from Qazigund to Banihal. The construction of this stretch posed several challenges akin to highly adverse geological conditions. Executing on -the -spot solutions, the project has been completed successfully. 1.0 INTRODUCTION Construction of Udhampur-Srinagar-Baramulla Broad gauge railway line is one of the Mega projects undertaken by Indian Railways to establish a dependable transportation in the state of Jammu and Kashmir. In engineering terminology, it is a challenging project negotiating breakthroughs against the complex Himalayan geology. The Project which has been operational over last 12 years , stretch by stretch, is in advance stage of construction . The purpose of the prestigious project is to connect the Kashmir valley to the mainland of the state of the country. On the date owing to the hurdles of the tuff terrain, the transport of this part is totally dependent on the surface transport, i.e., through a road which connects NH-1A from Delhi to Srinagar. The altitude of the region varies from 500.00 to 1700.00, ranging through Udhampur to Katra - Reasi –Sangaldan- Banihal-Quazikund-Ananthnag-Srinagar-and Baramulla. The main features of this project are its Pirpanjal Tunnel and T-48 & 49 tunnels which cover the maximum length of tunneling through thick hostile geological conditions, the total length being 138km. Details of Pirpanjal tunnels are shown in Figure-1."

Jan 1, 2016

By R. L. Atwood

This paper discusses the metallurgical and Manufacturing input to Merrill-Crowe plants. Topics treated are pregnant solution chemistry, clarification, degassing, zinc addition, product filtration, accounting, and costs.

Jan 1, 1985

By S. K. Sharma

The Bureau of Mines has investigated the fundamentals of the flocculation process. The objective of this study was to determine the effects of various physico-chemical parameters such as shear rate, polymer dosage, and polymer concentration on floc growth and to determine the applicability of a model in predicting polymer flocculation behavior. A rapid in-line particle size analyzer was used to follow the progress of both the floc growth and the breakage as a function of time. A genetic algorithm (GA) was used to determine the unknown parameters in the model and to fit a curve to the experimental data. Results show that the model, using GA as a tool to determine the unknown parameters, reproduces the experimental data with only reasonable accuracy and was relatively insensitive to the parameters. Results of the flocculation study showed that increases in polymer dosage had greater effect on the time required to reach the maximum floc size than on the floc size itself. It was also determined that, given all the aforementioned parameters, the degree of slurry mixing during the flocculation process had the greatest bearing on the floc growth.

Jan 1, 1993

An insufficient hydrologic data base exists for most large and small coal basins in Alaska owing to the lack of need in the past to collect data. The runoff process is insufficiently understood which is complicated by specifically northern phenomenon, and the lack of understanding of hydrologic relationships in permafrost environment. This paper presents an understanding of the hydrologic effects of frozen ground and presents methods by which the influence of surface mining upon the hydrologic balance can be analyzed.

Jan 1, 1988

High pressure grinding rolls have found widespread acceptance for cement processing, and are now making their debut in the metalliferous minerals industry. Significant energy and wear material savings appear achievable in many applications. This paper re- views the technical literature on this important, emerging technology.

Jan 1, 1997

By Eugene L. Foster

The engineering profession has traditionally devoted its efforts to understanding and modifying the Earth's environment in order to adapt it to man's needs. In appraising our overall performance, I would have to say it has been a mixed bag. In many areas, notably communications taken in the broadest sense, and development of creature comforts, we have done a good job. In others, we have failed, particularly in our assessment of the effect of our work on the environment. Our failures have been due in part to a lack of understanding or foresight, and in part to a disproportionate emphasis on lowest first cost. Now, with an increasingly large number of people living in a finite environment, there is an urgent need for reassessment. It is no longer possible to pursue a single objective without regard to its side effects. Our projects are too large, and there are too many of them. Environmental impacts must be taken into account in all important engineering decisions of the future. There are forces at work which will help to bring this about. Thinking people everywhere have realized that adverse alteration of our environment eventually affects every one of us. The majority of our citizens, who now live in cities, are beginning to appreciate the advantages of a good natural environment in a way which others who have been closer to the soil have appreciated for years. Our people have flocked to the cities because they wanted to be "where the action is." At the same time, there is a strong desire for what we have come to call the quality of life. Today, we all want the standard creature comforts. We want to be able to move freely

Jan 1, 1974

By T. Y. Yan

An effective elution technique has been developed for recovering uranium from ion exchange resins loaded in the carbonate leaching process. The procedure employs direct elution with acid. In comparison with conventional base elution, the procedure yields eluate of higher uranium concentration, results in a more complete elution, keeps the performance of the ion exchange resin at the fresh stage, reduces acid consumption, eliminates carbonate consumption, and reduces waste for disposal. The technique has been successfully demonstrated in the field and patented. It lends itself to commercialization.

Jan 1, 1987

By A. H. Brisse

In considering the use of a coal or a coal blend for the production of metallurgical coke, the fact is often overlooked that laboratory data can be most effectively used to determine coke plant operating conditions conducive to maximum output as well as to predict the quality of coke produced. The discussion here presented attempts to point out the manner in which carbonization data can be interpreted for industrial use and the significance of specific laboratory test results in this interpretation. The major considerable must, of course, be the safeguarded of coke oven batteries, against wall damage arising either from excessive carbonization pressures or from the wedging of the pushing ram into non-contracting coke charges. In order to be specific in the matter of handling the laboratory data involved, two series of blends are analyzed. The first of these, referred to as the "AB" series, is typical of some d' the more highly expanding Eastern- coal blends whereas the second series, here referred to as the "CD" series, is probably more typical of the Western coal blonds. Reference to Table II should be made for rank of coals considered in these blends.

Jan 1, 1959

By M. Li, J. K. Thompson, A. S. Azman

Powerful mining systems typically generate high-level noise that can damage the hearing ability of miners. Engineering noise controls are the most desirable and effective control for overexposure to noise. However, the effects of these noise controls on the actual hearing status of workers are not easily measured. A tool that can provide guidance in assigning workers to jobs based on the noise levels to which they will be exposed is highly desirable. Therefore, the Pittsburgh Mining Research Division (PMRD) of the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a tool to estimate in a systematic way the hearing loss due to occupational noise exposure and to evaluate the effectiveness of developed engineering controls. This computer program is based on the ISO 1999 standard and can be used to estimate the loss of hearing ability caused by occupational noise exposures. In this paper, the functionalities of this software are discussed and several case studies related to mining machinery are presented to demonstrate the functionalities of this software.

Jan 1, 2016

By Irwin H. Reiss

Gentlemen, the title of my paper is Surface Mining An Interim Land Use. Surface mining has become one of the major controversies of our time. This has happened in spite of the fact that all surface mining to date has involved only 6 million acres out of a total of 2300 million or approximately one-fourth of one percent of the total land area in the United States. I'm not going to dwell on whether peoples' perspectives are out of focus in light of the area involved, the energy crisis, national security, or the international balance of payments problem. While these things are all critically important, it is not the function of this paper to relate to them. Maybe the amount of attention attracted to surface mining is out of proportion to a lot of other things, but I don't feel that we should use that as a basis for procrastination. However, let me categorically state that anything that affects the surface of the earth is a form of land use --- be it an interstate highway, a power plant site, a golf course, a corn field, a strip mine, or the plot of ground on which your house is located.

Jan 1, 1974

By D. A. Curry

This paper describes a study of the influence of non-normal loading on the indentation behaviour of single bit-teeth. Indentation experiments have been performed on a soft, isotropic limestone using both sharp and blunt 60 degree wedge-shaped indentors constrained to penetrate the rock at 0, 15, and 30 degrees to the rock surface normal. For both sharp and blunt indentors, the normal force required to produce a given normal penetration decreased as the offset of the penetration direction from the rock surface normal increased. The crater volume produced by a given normal penetration with the sharp indentor was largely independent of the penetration direction. In contrast, the crater volume produced by the blunt indentor was increased markedly by non-normal penetration at small penetration depths, because the threshold penetration for chip formation decreased with non-normal loading. The crater volume produced by a given normal force was significantly increased by non-normal penetration, and this increase was particularly pronounced with the blunt indentor. The energy required to form unit crater volume was correspondingly reduced by non-normal indentor penetration. A simple method for predicting the reduction in the rock's resistance to chip formation is outlined, which is supported by the experimental data. The implications of these findings for rotary drilling are considered.

Jan 1, 1986

By William Wargo

The basic reason for lining underground cavities is to keep the cavity open during its useful life by providing adequately for the support of the surrounding rock and for the necessary degree of water tightness. This covers the entire field of support methods from the simpliest timber support to reinforced concrete in all its variations as applied to tunnels, galleries or shafts. The problem involved in the design of more efficient and economical lining systems for even bigger cavities has been magnified by increased speed of advance made possible by better blasting tecniques, improved tunneling machines and more efficient material handling. Tunnel lining today requires a disproportionate amount of time and money compared to other operations mostly due to the manuel labor involved in its installation. One solution to this problem is the developement of an entirely new concept in tunnel lining designed notoonly to overcome this bottleneck but also to open up the field for further increases in speed of advance. This new lining system acts first as a fast protective armour then becomes the concrete metal form and ends up as reinforcement sheet inside the concrete lining. This system developed and manufactured by Bernold A. G. of Switzerland since October 1968 has been installed in 25 applications in Europe under all ground conditions from stable rock to unconsolidated ground.

Jan 1, 1970

By Simon J. McDonald

In late 2007 Neptune Minerals Plc. commissioned Genesis - a leading consultancy and engineering company affiliated to the Technip group - to undertake a Seafloor Mining Conceptual Study for mining of Seafloor Massive Sulphides (?SMS?) in Neptune?s New Zealand licenses. A key deliverable of the study was information to de-risk the perception of SMS mining for investors the minerals, and that deep-sea mining of SMS material is technically feasible, commercially viable and can safely be managed as a sustainable marine resource industry. The aim of the study, completed in April 2008, was to evaluate alternative existing marine technologies for seafloor mining, ore lifting, dewatering and surface offtake, considering the following parameters: ? Efficiency; ? Reliability; ? Safety; ? Environmental impact; and ? Cost

Jan 1, 2008

By Y. C. Kim

One aspect of long-range mine planning in an open-pit mine is first to define the ultimate pit limit, i.e., the projected size and shape of the pit at the end of its life. This chapter is concerned with various techniques that are currently in use today in determining the ultimate pit limits using the computer. Prior to the early 1960's, open-pit limits analyses were entirely performed manually. This manual technique has been well explained by Soderberg and Rausch in Surface Mining (1968). Soderberg and Rausch also explain clearly the need for establishing the ultimate pit limits in long-range mine planning, i.e., location of surface facilities, dumps, etc. Consequently, the need for ultimate pit limit design will not be reiterated here. Nor will the definitions of the most commonly accepted terminologies such as break-even stripping ratio, economic cutoff grade, ultimate and working slope angles, preproduction stripping, etc. be repeated here. Briefly, the objective of the ultimate pit limit design (which is also frequently referred to as pit design in short) is to determine the projected final pit limits of an ore body and its associated projected grade and tonnage, which will maximize some prespecified economic criteria while satisfying practical operational requirements.

Jan 1, 1979

By R. F. Kovar, R. N. Torbin, R. E. Gundersen

I have to express my .surprise and must send a note of warning concerning the use of polyurethane foam as described in a paper by R.N. Torbin and R.F. Kovar, entitled "Innovative Shaft Lining Method," published in your February 1989 edition. In September, 1986, 177 miners lost their lives when they were exposed to fumes downwind from a fire in a tunnel lined with polyurethane foam. Whilst polyurethane exhibits reasonable fire retardent properties in small-scale tests, mass use in a tubular configuration, exacerbated by the furnace effect of cross-radiation, can lead to a rapid, uncontrollable conflagration. I do not wish these comments to detract from the engineering achievements of the authors but rather to sound a loud warning as to the application of the system. Any shaft designed for human access- be it for transport or shaft work - and any intake airway, should not consider the use of polyurethane foam. It only needs a slip with a cutting torch or an electric fault to initiate a disaster. Many countries have banned or restricted the use of polyurethane foam in the workings of a mine and maybe alternative foams (e.g. phenolics) can be used or developed

Jan 1, 1991

By Theodore H. Eyde

The porphyry copper province of the southwestern United States and northern Mexico, is the largest copper producing region in the world. Most of the deposits occur in Arizona which now produces over 54% of the newly mined copper in the United" States. As the many recent discoveries are brought into production, Arizona's share of the nation's copper production will increase. The term "porphyry copper" as used in this paper includes all deposits of generally low grade disseminated copper mineralization amenable to bulk mining techniques. Therefore, copper deposits such as Pima-Mission, Twin Buttes, and Vekol where the copper mineralization occurs principally in the intruded rocks will be considered as "porphyry copper" deposits. Most of the deposits have been discovered since World War II, consequently, the southwest, and particularly southern Arizona is perhaps the most intensively explored area for copper deposits on earth. Most of the major natural resource companies in the United States and Canada maintain exploration offices in southern Arizona. To illustrate the success of exploration efforts, the location of porphyry copper deposits either known or producing prior to World War II are shown on figure 1 and the deposits discovered since World War II which are either in production or in the exploration and development stage are shown on figure 2.

Jan 1, 1973

By Don Rose

Steel-fiber-reinforced-shotcrete (SFRS) methods of testing and the wording of specifications vary from country to country. In the USA ASTM C1018 is widely used. The Canadians have taken a close look at C1018 and point out that exact determination of the first crack is very subjective, and they propose a method of design that eliminates this variable. The Europeans (EFNARC) have taken the principles of testing a step further than ASTM C1018, and have added a new step in measuring the effectiveness of SFRS. EFNARC uses an "energy absorption" of a plate loaded in its center, in addition to the principles of C1018. The principles of SFRS design are also used in Japan, Norway and elsewhere.

Jan 1, 1999

By J. A. Ryder

Compressed air is a relatively inefficient yet very convenient vehicle for transmitting mechanical energy. It is inefficient when compared to, say, hydraulic or electric energy systems since compressor and pneumatic machine efficiencies are quite low (in the range 20-65%) and reticulation losses can be quite high unless adequate pipe diameters are used to minimize friction drops. It is convenient in that capital and maintenance costs of pipes and machines are exceptionally low, the equipment is flexible and lightweight, the technological level is simple, the form of the energy supply is intrinsic- ally safe, and as an additional minor but psychologically important benefit, it provides a ready source of cooling and air supply for emergency use in deep hot mines. It is for these reasons that compressed air is a premier source of energy for many forms of underground equipment, in particular hand or rig-mounted rockdrills, some forms of rock- handling equipment, and a host of minor applications including agitators, small-lift pumps and temporary f am installations. In a typical S. African deep-level gold or platinum mine, compressed air generation accounts for 15% of the total mine electrical energy bill - more than is used for hoisting. In these mines it is not uncommon for over 100 km of underground compressed air piping to be installed, primarily to supply handheld rockdrills.

Jan 1, 1979

By Miguel Angel Ibarra

This paper describes the results of a digital computer simulation study in which the impact of the proposed truck dispatching on the overall mine productivity was investigated for an operating open pit mine. In the study, the existing operation was first simulated for a one-month period, using both the actual time study data and the computed cycle times. By adjusting certain input parameters to the simulation program, the actual one month production was first duplicated through simulation. Afterwards, the operation was again simulated in a dispatch mode. Comparison of simulation results under the dispatch mode, with the initial base case simulation results, showed a definite improvement in overall productivity with dispatching; i.e., approximately 10% gain for the operation. As expected, the results also showed that the extent of possible improvement did vary with the particular pit configuration being investigated.

Jan 1, 1980

By J. Launay

In order to control and dispatch the sewage water coming from 3 tunnels toward 2 downstream sewage tunnels, a large cavern has been excavated in a suburb of PARIS. Located at a depth of 47,00 m, it has been excavated using the NATM procedure through swelling clay, weathered sandstone, and marl and chalk. It is 16,50 m high, 12,40 m wide and 60, 00 m long, with an elliptical cross-section and its two ends are egg-shapped. The final lining of the cavern is composed of 30 to 40 cm of shotcrete, steel ribs and passive anchor bars. The excavation stages and related movements were surveyed by extensometers, pressure cells and convergence devices. The design, method of construction of the cavern and the results of the measurements made are commented.

Jan 1, 1989