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By J. A. C. Ross

Introduction To enlighten those who may be wondering where anyone could find sufficient data to write a paper on underground concrete work, the author would like to explain that, at Copper Mountain, we have found it necessary to line numerous headings with a layer of concrete in order to keep them in a safe and serviceable condition. The majority of these headings are scram drifts and ore-pass raises. This paper will therefore deal, in the main, with the methods of and reasons for placing concrete in these headings. During recent years, radical changes have been made in the methods of mining ore at the Copper Mountain mine. After considerable experimenting, a mining system has been developed making use of diamond drills for primary breaking and transfering such broken ore through scram drifts with slusher hoists. With the advent of scram drifts, it soon became apparent that some substantial means of reinforcement and protection for the scram drifts themselves would be necessary. Since the orebodies in this mine are cut by numerous dykes or faults, and often both, it was anticipated that some means of support would be required where headings necessarily passed through these incompetent zones. Further, as experience was gained, scram drifts were driven into pillars and in close proximity to old workings so as to recover the maximum amount of ore. In such places, the ground is often severely fractured, either as a result of previous mining or from the effect of excessive rock pressures.

Jan 1, 1950

By William R. Nash

Case histories of water problems in underground mine shafts and tunnels are outlined to illustrate varying degrees of sophistication in grouting techniques currently applied in such construction. The interception of water underground can be one of prior knowledge, i. e., the site investigation provides necessary data to plan a grouting program prior to construction start, or excavations may encounter "changed conditions" or unplanned water. The latter includes catastrophic inflows and emergency situations where the structural integrity of a building or concrete shaft lining are jeopardized. The presentation of this paper outlines some applications of grouting work in underground mine construction throughout the United States in a variety of geological provinces and for a variety of minerals.

Jan 1, 1984

By L J. Strachan, O J. Hawes, S W. Crossen, R C. Roberts

The Albany Conglomerate is a widespread geological unit found in northern areas of Auckland, New Zealand. It has previously been described as part of the early Miocene Waitemata Group which underlies most of Auckland. Much of the Waitemata Group comprises weak interbedded sandstones and mudstones, but also includes conspicuous conglomeratic units such as the Albany Conglomerate. The Albany Conglomerate comprises a well-cemented mixture of hard pebbles, cobbles and boulders of igneous and metamorphic derivation in lenticular beds. A number of tunnelling projects are planned for the near future in Auckland. Recent experience has shown that the variable features associated with the Albany Conglomerate can make selecting appropriate construction methods very challenging. This paper explores the engineering geological and sedimentological features of the Albany Conglomerate with respect to other conglomerates within the Waitemata Group and the potential implications on tunnelling projects in Auckland. Consideration is given to the extent of proposed geotechnical investigations and the production of geotechnical baseline reports.CITATION:Roberts, R C, Hawes, O J, Crossen, S W and Strachan, L J, 2014. Underground construction challenges associated with the Albany Conglomerate in Auckland, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 195–202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By John L. Kaplin

The underground construction for the Phase I Combined Sewer Overflow(CSO) Project is on an impressive scale by any measure, appearing more so in a midsize city like Providence, RI. The Narragansett Bay Commission recently completed $350 mil-lion in construction to improve the water quality in Narragansett Bay. This project included a number of serious challenges, delays, and disputes. Looking back on this complex project completed within budget, it is hard to consider the work as anything other than a success. Along the way, this outcome did not always appear certain.

By Steve Karl

"The global underground construction and tunneling industry is in pretty good shape. Billions are being spent in shoring up aging infrastructure in the United States and other places, and new underground projects are being put out for bid.With each new project, comes new equipment, technology and tunneling methods. So it is incumbent on tunneling professionals to constantly improve their knowledge of the profession. This is where spending a few days with other underground construction professionals can assist the tunneler in keeping up.Every two years, tunnelers and underground construction engineers, contractors, suppliers, designers and owners from around the world gather for the Rapid Excavation Tunneling Congress (RETC). The 2017 conference was held in June in San Diego, CA. The UCA of SME puts on the conference.This years’ RETC attracted 1,400 attendees. The accompanying sold-out exhibit totaled 188 service and equipment suppliers. In addition, the conference had the UCA of SME bookstore, where the new History of Tunneling in the United States book was introduced. And a short course on tunnel rehabilitation was featured.Technical programmingRETC 2017 featured nearly 100 technical presentations. Topics covered the breadth of the global underground construction industry. Here is a sampling of a few. The proceedings from the conference is available from SME, 303-948-4200, www.smenet.org.Accomplishing extraordinary tasks as a machine supplier for Metro Doha: The construction of the Metro Doha in the State of Qatar established a modern, safe, efficient and integrated public transportation network. Upon final completion of multiple phases, the network will comprise four metro lines with a length of 216 km (83 miles) and 100 stations. Phase one comprises 112 km (43 miles of underground tunnels (56 km or 22 miles of twin-tube tunnels). Twenty-one earth pressure balance tunnel boring machines (TBM) were deployed by the four different joint ventures. The project was initiated, managed and supervised by the owner, Transport Authority Qatar Rail.Phase two of the Doha Metro will start upon the completion of Phase One in 2019 (Qatar Vision 2030). The owner placed full faith in the manufacturer’s abilities to deliver equipment of high quality, state of the art standards within the given time frame. This paper focused on the manufacturer’s scope of delivery and on the supplier’s high standards of quality in production, logistics and services."

Jan 9, 2017

When the 2008 Olympic Games begin in Beijing, China is September it will not only mark the end of the journey for the Olympic torch and the thou-sands of participating athletes, but the games will also mark the culmination of a massive amount of construction in the city. On display for the world to see will be 31 new and refurbished venues including the 91,000-seat National Stadium called the ?Bird?s Nest? and the aquatics center, called the Water Cube. What will not be featured as prominently on the television cameras broadcasting the games around the world will be the network of tunnels built beneath the city. But that infrastructure of rail lines will be of critical importance to the games. While preparing to host the world, China added a subway tunnel that will include four stops in the Olympic Park. The 4.4-km (2.7-mile) subway line that runs through the complex of stadiums, gymnasiums and parks began trial operations in June. Prior to the opening of that line, Beijing's No. 5 subway line, which runs through the heart of the city from north to south, opened in October. That 27.6-km (17-mile) line took nearly five years to build and includes 23

Jan 1, 2008

By Susan L. Bednarz

Recent advances in digital cameras and image processing allow photographers to produce excellent high-resolution action shots in low light and high contrast conditions commonly encountered underground. Digital photography is often used for construction and inspection documentation for underground structures. Designers, owners, and contractors benefit from quality photographs that document incremental progress and project milestones. Documentation photos serve as a lasting record of as-built conditions, are an important marketing tool, and help the owner build public support for expensive public works projects. When the project is complete, the only mementos that the participants will hold onto are the photographs.

Jan 1, 2008

By David Forrester

"At the 95th CIM Annual General Meeting in Calgary, 1993, a paper entitled “Progress on Futuristic Mining Technologies” was presented(Matthews and Sarin), in which they outlined the goal of continuous excavation of hard rock and some of the technologies being developed to achieve it. The subject continues to be featured in periodic reviews and articles in the literature, (Gertsch, 1994; E&MJ, 1995). Matthews and Sarin note the considerable success of the development and application of continuous mining technologies in the soft rock under-ground mining industry, especially those in coal and potash, with major benefit to overall production, productivity and economic viability. It is the belief that similar achievements can be realised in the underground hard rock mining which continues to drive the development of hardrock continuous mining technology.This overview has been prepared specifically for this issue of the CIM Bulletin. It attempts to tie together current advancements in continuous mining in soft rock (where remote control and automation are already well established) with the background and status of development in hard rock continuous mining. Following a brief review of key factors and machine types, soft rock aspects are discussed, then a more detailed review is given of hard rock technology, with particular reference to Canada’s HRDK Mining Research Ltd. and their key role.The mining industry has long been at the forefront of technology development, for example, the application of the early steam engine to reach reserves at greater depth for dewatering mines in the industrial revolution. By necessity, the individual characteristics of seams and orebodies dictate the mining method, continually presenting mining engineers with new challenges. One of these is the extraction process itself and the goal of replacement of the drill-blast-muck cycle by continuous excavation. Very soft rocks have always been mineable using some form of cutting, even with primative tools. However, as the challenge has been taken up, technologies have evolved to steadily increase the hardness of rock that can be mechanically excavated. It may surprise some readers that at least three machines have successfully cut and loaded rock with an unconfined compressive strength (UCS) of 250 Mpa to 300 MPa (36 000 to 43 500 psi) in field trials (Table 1)."

Jan 1, 1996

By G. S. Brierley, R. D. Drake, J. E. Kelley, J. C. Kellogg

This case study embodies the problems of an underground project under current contracting practices. It will provide a realistic framework for a structured examination of the anatomy of a major complex underground project. Just as it will illustrate the frustrations of the parties to an underground contract, it will also provide a means to examine potential opportunities to provide a better way to develop underground space. Urban Transit Authority (UTA) had planned to expand their heavy rail underground transit system through an extension to an existing line. UTA lacked sufficient funding to guarantee the construction and operation of this planned extension. Venture Partner Associates (VPA) in conjunction with four major department stores entered into an agreement to create a major underground space for a commercial/recreational facility. The concept was to locate the facility adjacent to a planned station and beneath existing aboveground office facilities. This group was known as Commercial Development Corporation (CDC). UTA had reached an agreement with UMTA to provide 20 percent of the line and station costs. UTA then entered into an agreement with CDC to provide the needed additional funding for the station work in return for locating the station adjacent to the planned underground commercial/recreational complex. The agreement called for CDC to contribute 20 percent to the station cost to a maximum of $25 million plus a one percent contribution from commercial/recreational revenues for operating costs.

Jan 1, 1989

By Howard M. Graff

The Inland Steel Company operates five underground iron mines in the Lake Superior District. The two largest of these, from the standpoint of productive capacity, are the Sherwood Mine in Iron River and the Bristol Mine in Crystal Falls, both on the Menominee Range of Michigan. It is at these two mines that we have had our principal experience with belt conveyor installations underground, .At the Sherwood Mine, which has an annual capacity of about 450,000 tons, the first conveyor belt installationwas made in 1947 when conveyors were installed in the main haulage drifts on the 1200 ft, level, It was estimated at that time that approximately 5,000,000 tons would be mined from the stopes above the 1200 ft, level and. that if all this material could be moved to the shaft by belt conveyor, the entire cost of operation, including maintenance and the amortization of the equipment, would be about $,05 per ton, which was slightly more than half of what the cost would have been by conventional tramming methods employing locomotives and cars. Now, ten years later, the 1200 ft, level is almost completely mined out and we have actually removed. 5,200,000 tons and. the average cost of transporting this material to the shaft by belt conveyor has been $.095 per ton. Since there has been a substantial increase in hourly rate of pay and also in the cost of materials since 1947, we feel that the anticipated savings were very nearly realized., The 1200 ft, level installation at the Sherwood consisted of two 36" trunk line conveyors 815 feet long and 380 feet long, respectively, deliverying ore to the shaft. These in turn were fed. by three lateral 36" conveyors which paralleled the sides of the orebody, These gathering conveyors passed under draw points to which ore was brought from the stopes by mea S of scrapers or shaker conveyors, Shaker conveyors were used for a number of years in conjunction with the conveyor belt system of haulage but it was finally concluded that with this particular type of ore, the maintenance on shaker conveyors was excessive. Therefore, more recently, we have gone back to scrapers for the shorter distances and. are using belt conveyors in the scraper drifts for the longer distances. After this belt system had been in operation for about three years, it had proved to be so successful that it was decided to proceed with the same system or. a new level to be opened up 200 feet below. Instead of sinking the shaft and driving a horizontal drift to the orebody on the 1400 ft, level, an inclined conveyor drift was started near the shaft at the 1200 ft. level and driven downwards toward, the orebody at a slope of 15 degrees. The conveyor installed in this inclined drift is 36" wide, 990 feet long, is powered. by a 100 hp motor, and is capable of delivering 300 tons per hour to the 1200 ft, level shaft pocket. It is fed by lateral horizontal conveyors on the 1300 ft? 1400 ft., and 1425 ft, sub levels. Wien the inclined drift was started, the rock was scraped from the breast directly to the rock pocket at the shaft. As the distance increased., double scraping was employed, until the advance had reached 350 feet, At this point a portion of the final conveyor was installed, with a scraper slide near the breast, T e drift was then advanced be scraping on to the conveyor until a sufficient distance had been driven to permit the installation of an additional 200 feet of conveyor. This proved to be a very efficient and economical means of moving the development rock to the shaft and obviated the need of using cars or an inclined skip way, At the present time 85 percet of tie entire mine output is being mined below the 1200 ft, level and is delivered to the shaft via the inclined conveyor. The system appears to be working as well and as economically as did the conveyor systemonthe 1200 ft, level.

Jan 1, 1958

By Hugh P. Godard, K. Winslow

"AbstractA number of panels of various aluminum alloys in different combinations and secured by steel and three types of aluminum rivets were exposed underground at two locations in a Northern Ontario gold mine for two years and then examined to determine the extent of corrosion. The results indicate Alcan 65S-T to possess considerable advantages over Alcan 178-T, which has been employed in the construction of light skips and cages with considerable success for almost twenty years. Information on the behaviour of these alloys when used with steel rivets and in mixed combinations with themselves was obtained.IntroductionBy the complete substitution of aluminum alloys for steel in the fabrication of mining skips and cages, their weight can be reduced as much as 50 per cent. Lesser savings are possible though its savings are possible through its plates, doors, reinforcing members, etc. Reduced weight leads to economy through increased hoisting efficiency.For a new installation, the basis of design is the rate of production, which thus fixes the live load to be hoisted per trip. A lighter skip permits the use of a lighter rope and a smaller hoist. In deep shafts with high-speed hoists operated in balance, the power required for accelerating is considerable. The hoist size is determined by the weight of skip, load, and rope plus the force required to accelerate or decelerate these three elements A light skip may result in a considerably lighter rope. This is important because, even though the skip can be completely balanced this is not true of the rope. Partial balancing is possible, but conical hoist drums or other devices for this purpose are costly; thus a smaller rope results in a smaller hoist, with consequent general reduction in cost of the whole installation. A reduction in power consumption is also obtained as a result of keeping to a minimum the amount of unbalanced load and the weight of all moving parts which must be accelerated."

Jan 1, 1950

By S. K. Paul

"This paper briefly describes the underground crushing and conveying system at Sherritt Gordon Mines' Ruttan Mine. A series of three steel-cord belted conveyors, with a total length of 2J55 metres and a total vertical lift of 407 metres, convey the muck from the underground crushing station to the mill at the surface. The maximum size of the crushed rock is 6 in. All the conveyors are provided with numerous safety and fire suppression devices. IntroductionThe Ruttan Mine of Sherritt Gordon Mines Limited is located 20 km east of the town of Leaf Rapids, 760 km north of Winnipeg. The orebody is multilensed, with lens width varying from 6 to 45 m. Ore production started in 1973 with the opening of a 10,000-tpd open-pit mine. Initial development of the underground mine was started in 1972 with the driving of parallel conveyor and access declines at minus-2507o gradient to the I 220-m level, and then the access ramp was further extended to the 1160-m level. Exploration drifting was done on the 1280-m and 1160-m levels from the access ramp. The final development plan for the underground project was approved in January 1977, and full-scale development and constructionwere resumed.At present, Ruttan Mine is in a period of transition from open-pit to underground mining. Ore production is now coming from both operations. By mid-1980, open-pit production will cease and all production will come from the undergroundmine.The underground mining method at the Ruttan Mine is sublevel open stoping with delayed backfilling. The orebody is divided along strike into a series of 27-m-long stopes and 15-m pillars, both 60 m high."

Jan 1, 1980

By O. E. Andrew

THE object of this paper is to present a brief summary of the dust control system in use on the 3,825-foot level at the jaw crusher station, Lake Shore mine. During the years 1936 and 1937, dust survey reports were presented to the management showing that high dust concentrations were being created during operating periods. At that time, however, this crusher was running only an hour or so each shift, and it was felt that no large capital expenditure for dust control equipment could be justified. In order to afford some protection to the operators, a number of respirators then on the market were .tested and the 'Comfo' respirator was adopted for use by the crusher-men. In 1938 this crusher began to handle a large share of the total mine tonnage and the hours of operation were increased. Further dust sampling showed increased dustiness with the longer operating time. It was also realized that the operators suffered considerable inconvenience if they wore their respirators throughout the shift. If the respirators were not worn, then dangerous amounts of dust were being inhaled. The fact that the crusher station was situated on the 3,825-foot level limited the means that could be employed to eliminate the dust hazard. At that rime there was not available the 5,000 c.f.m. of fresh air which would be required to sweep out or dilute0 the dust, and there was also no way of disposing of the contaminated air without passing it on for other men to breathe. Thus it became apparent that a self-contained dust disposal system would have to be installed.

Jan 1, 1941

The limit of pressure to which an underground dam may with safety be subjected, is a question that-as far as the writer knows has not received the same attention from authorities on engineering construction, or practical mining, that has been accorded to questions on which the design and strength of other structures or machines in connection with a mine are based. That dams may, under certain conditions, be constructed to resist water under great pressure is a known fact. But the difficulty of demonstrating beforehand that any proposed structure of this kind will withstand the pressure and be effective is, owing to the indeterminate nature of some of the risks to be provided against, very great. In the present state of our knowledge it may almost be laid down as a rule, that a dam of this kind should not be undertaken where grave consequences would attend failure until experience of structures where the physical conditions are similar, but where there are no such risks, has given assurance that such work would stand.In Mines and Minerals for May, 1900, there is published a paper by Mr. James McNaughton describing the construction of three underground dams in the iron mining district of Michigan.The first of these was put in to hold back a flow of 750 gallons per minute, which when pent up created a pressure of 276 pounds per square inch, showing that the height of the sustained column was about 635 ·feet. The hole through which the water issued was in the bottom of the cross cut it was enlarged by removing all loose rock for a depth of 18 ft...

Jan 1, 1901

By W. F. Netzeband

THE zinc-lead mines of the Eagle-Picher Lead Co. are situated in the Tri-state district of Oklahoma-Missouri-Kansas. The company is operating, at the present time, seven mines in the brecciated deposits of the Picher, Okla., camp; two in the water-course ground of the Treece, Kans., camp; two in the open, boulder ground of the Crestline, Kans., camp; and one in the sheet ground of the Pierce City, Mo., camp. The accompanying map (Fig. 1) shows the relation of the rich narrow runs to the other ore-bodies of the district. The runs are designated by cross-hatching so as to distinguish them from narrow drifts that have been driven as prospect drifts or haulage drifts. Figs. 2, 3 and 4 are cross-sections showing the type of formation encountered in the operation of the drills. The Picher camp is in the brecciated type of deposit with some water-course ground encountered, usually near the edge of the deposit. These deposits are flat and fairly uniform so that they can be mined systematically. However, scattered between these deposits are narrow runs that are usually very rich. Up to the present time, most of the prospecting has been done from the surface with churn drills, supplemented with some prospect drifts in the ground, once the mine is opened up. Prospect drifts are expensive, do not give much information except the presence or absence of ore and are therefore not used to any great extent. In the early days of the camp only the larger deposits were found and mined, with an occasional narrow run which was drilled out more or less by sheer luck. Later, more of these narrow rich runs were found and mined, until today many of the properties that were formerly considered worked out are being leased and re-drilled. It is very evident that many of these narrow runs, which are often only 20 ft. wide, can easily be missed by drilling from the surface unless very close drilling is practiced. This, of course, becomes very expensive as there are from 150 to 250 ft. of

Jan 11, 1926

By Bradford F. Townsend, Gary Peach, Roger Rothenburger

From the experience of the authors on recent large infrastructure Design-Build projects this paper reviews major lessons for Contractors and Owners in the delivery of large Design-Build infrastructure projects and some major pitfalls and warnings to both Owners and Contractors. The paper is written from both the Design and Construction perspective. A case history is presented that details the approach employed to ensure a quality project consistent from the initial design phase through construction and outlines the strategy used to guide the Design-Build process to an acceptable completion. Suggestions are made for Contractors and Owners for handling the Design and the Construction elements of Design-Build contracts.

Jan 1, 2003

By R. M. Barker

The historic Getchell property, near Golconda, NV, is being mined from the Getchell Main Under- ground workings, a footwall extension of the Getchell open-pit deposits along the Getchell fault. Drift-and-fill techniques are used to extract the ore through a ramp access. The adjacent Turquoise Ridge deposit is under development by two vertical shafts. These two mines will continue to provide feed to the Getchell's 2.9 ktld (3,200 stpd) mill/autoclave circuit. This will take Getchell Gold from its current production rate of 6.2 t/a (200,000 oz/year) to more than 12.4 t/a (400,000 oz/year) by 1999.

Jan 1, 1997

Operating and Social Considerations from a Contractor?s Perspective

May 1, 2013

By J. A. L. Campbell

The Galatia Mine is a dual-seam underground coal mine located in Saline County, IL. In 1984, it became the first coal mine to be permitted by the Illinois Department of Mines and Minerals to operate diesel equipment underground. And it is one of the larger underground coal mines in the nation to use diesel equipment. From the beginning, Kerr-McGee determined that diesel equipment offered the best approach to the safe and productive development and operation of the Galatia Mine. The flexibility of this equipment and its ability to promptly respond to changing conditions and mining locations made its use desirable for building this large dual-seam coal mine. The mine had a planned nominal annual capacity of 3.6 Mt/a (4 million stpy) and would employ more than 500 people. Galatia's current reserves are estimated at 231 Mt (255 million st) of recoverable coal from two seams of high-quality, high-volatile bituminous coal. The Harrisburg No. 5 seam is shipped primarily as a low-sulfur steam coal or as a metallurgical blend stock. It is also used in the pulverized coal injection (PCI) process for steel making. The Herrin No. 6 seam is a medium-sulfur coal. Annual production is shown in Fig. 1. A good indicator of a mine's success is employee productivity improvement. For many reasons - the proper use of diesel equipment, the introduction of longwalls and increased employee ex¬perience - Galatia employees have achieved a steady growth in annual productivity (Fig. 1) while maintaining an exceptional safety record.

Jan 1, 1993

By John R. Marks

The first 0.7 m3 (1 cu yd) diesel load- haul-dump vehicle (LHD) arrived at the Homestake Gold Mine in Lead, SD in I969 to muck a ventilation drift. Others soon followed. Mechanization has subsequently changed stoping methods, manpower requirements, ventilation practice, the definition of minable reserves, and it has impacted safety and health. These have all had a direct bearing on the economics of producing gold ore from deep underground. Mechanized mining Before mechanization, production quotas at Homestake were met by several open cut-and-fill (OCF) mining methods. OCF mining relied on jackleg and wagon drilling, electric and compressed air slushing and cribbed raises brought up through the fill. Even square- set stoping was used until about eight years ago. The mine became 100% mechanized in 1988. The two current stoping methods are mechanized cut-and-fill (MCF) and vertical crater retreat (VCR). In 1992, MCF accounted for 54’S, VCR for 44% and development/uphole for 2% of the 1.4 Mt (1.55 million st) of underground ore produced. These methods are typically ramp- based and use diesel-powered LHDs, trucks, pneumatic drill jumbos and utility vehicles. Electric LHDs and rubber-tired compressed air muckers have also been used in VCR scrams. Pfarr (1991) and Mitchell (1980) provide good overviews of current production methods.

Jan 1, 1993