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By Morteza Gharouni Nik

Flexible Dilatometer Test (FDT) is one of the in-situ test methods for determining the deformational characteristics of rock masses. In this study, several dilatometer tests have been conducted in different geotechnical phases of site investigations by means of two types of FDTs. The purpose of this paper is comparison of the performance of these two types of dilatometers and analysis of the differences in the results of the tests.

Jan 1, 2008

By Charles S. Robinson

INTRODUCTION Geology, the science of the earth, is the fundamental science in the construction of a tunnel. The approximate site of a tunnel is determined by its purpose. The geology of the tunnel site will determine the cost--or feasibility of a tunnel--the specific alignment to accomplish the purpose of the tunnel, the design of the tunnel (within the limits of the purpose of the tunnel), and the methods of construction. The more accurately the geology of a proposed tunnel can be depicted, the more accurately can the cost of a tunnel be estimated. The factors that should be defined for tunnel design and construction are the physical characteristics of the material in which the tunnel is to be constructed. The physical characteristics of the material are determined by the genesis of the material, and subsequent geologic processes that have affected the material. The geologic materials in which tunnels are constructed can be broadly classified as unconsolidated and consolidated. The unconsolidated materials include chiefly deposits of recent geologic time that occur near the surface. Because these deposits occur near the surface, and tunnels constructed in them will be at shallow depth, methods of physical exploration such as geophysical methods, trenching, and drilling will give more data at relatively low cost--therefore the physical exploration is generally, or should be, quite extensive--and the

Jan 1, 1997

By Don Phelps, Dean Brox, Peter Procter, Andy Saltis, Tom Morrison, Jeff Pringle

The Greater Vancouver Water District is currently constructing the Seymour-Capilano Water Filtration Project to enhance the quality of drinking water in the Vancouver metropolitan area. The Seymour-Capilano Water Filtration Project comprises the 1,800 million litres per day Seymour-Capilano Filtration Plant, the 1,080million litres per day Capilano Pumping Station, twin tunnels with associated shafts, and the Capilano Energy Recovery Facility. The twin tunnels will convey raw water under pressure from the Capilano Reservoir to the Seymour Filtration Plant and return treated (filtered) water for distribution. The Twin Tunnels component of the project comprises twin, 3.7 m diameter, 7.2 km TBM bored tunnels, the 180 m deep Seymour Shaft as the main launch shaft, and two 4 m diameter, 268 m deep raise bore exit shafts at Capilano. The Twin Tunnels have been planned as predominantly unlined tunnels sited at depth entirely within granitic bedrock and cross under two major buried glacial valleys of breadths in excess of 1500 metres that are filled with glacial sediments to depths up to 200 metres. The maximum overburden along the tunnel alignment is approximately 400 metres. Comprehensive site investigations and studies were completed during the detailed design stage of the project. The construction of the twin tunnels started in the fall of 2004 and is planned to be completed by mid-2008.

Jan 1, 2005

By Brent Duncan, Doug Harding, Bob Stier

The 73rd Street Tunnel Project is part of “The Tunnel and Reservoir Plan” (TARP)also known as the Deep Tunnel Project, and is located in the Village of Bedford Park, County of McCook, State of Illinois. The project consists of a ø 4.42 meter × 2,060 meter long (14´-6? bore, 6,760 foot)tunnel. The completed tunnel is used as a bypass tunnel for the McCook Cup Reservoir Project. The project was awarded to Affholder Inc. of St. Louis, in 2000. The paper describes the project in which a new, high-powered open gripper type main beam machine was used in which high advance rates have been achieved using conventional muck haulage techniques. Features of the project include the installation of rock support consisting of counter-sunk rock bolts that are required to be pull-tested for strength per project specifications. Installation and testing of the bolts are done during the boring cycle. Muck haulage was done by conventional muck car train and hoisting at the construction shaft. As the site layout did not include a tail tunnel, the trains needed to be shuttled at the shaft bottom. Even with the bolting requirements and the muck haulage without a tail tunnel, the Affholder site personnel still achieved high advance rates on the 73rd Street Project.

Jan 1, 2003

By J. S. Chen

DOE recently funded 21 projects under the solicitation by its Environmental Restoration and Waste Management Division. This project is combining the expertise of an interdisciplinary team of researchers with that of three manufacturers to isolate nuclear waste storage sites using remote longwall mining. The concept is being pursued in Germany, too. This paper will present the conceptual approach to the project and discuss the problems in transferring longwall mining technology to nuclear waste containment.

Jan 1, 1994

By M. Murphy

The multibillion dollar cost of cleaning up thousands of environmentally contaminated sites across the country created by decades of inadequate disposal of hazardous waste has led to a search for "deep-pocket" sources of cleanup funds. The resul1:: is the emergence of a growing body of law that could have a profound impact on commercial financing transactions and other investment activities when present or past owners of contaminated property are involved.

Jan 1, 1988

By H. O. Harju

In July 1968, P.T. Inco Indonesia was granted a Contract of Work to explore and develop the nickel laterite resources on the southeastern peninsula of the island of Sulawesi. Since 1970, exploration has centred on the deposits at Soroako as the site for initial project development. This paper describes the exploration methods used to evaluate these rather unique laterite deposits, the geology of which is described in the first section of this volume.

Jan 1, 1979

By K. Fuenkajorn

Geomechanics and geohydrological considerations for the seal design for mine openings are presented. Design guidelines derived from laboratory and in-situ experiments are proposed. The results suggest that seal design, specifications and material selection should be site-specific. Performance requirements for a specific seal location should be identified. Evaluation of sealing effectiveness should be made on the entire seal system, i.e. seal, seal-rock interface, excavation-induced damage zone and the surrounding rock.

Jan 1, 1997

By T. J. Toy

The topography reconstructed following land disturbance is the foundation for all other reclamation practices. As the manufactured drainage basins, hillslopes, and stream channels approach a steady-state condition, the amount of adjustment of these landforms by geomorphic processes following reclamation decreases. As the adjustment required to establish a steady-state condition decreases, the prospect of reclamation success increases while the prospect of site maintenance decreases. Careful topographic reconstruction is a good investment.

Jan 1, 2002

By C. Dale Elifrits

Observations made from laboratory analysis of samples of fine-grained argillaceous materials (shales) subjected to various changes in moisture content have been correlated to loss of strength in the rock material. This reaction to a change in in-situ conditions (subsequent to mining) at a mine site combined with the observed relationships of surface-disturbing subsidence features at locations where the predominant overburden material is fine-grained, provides a predictive tool for the subsidence engineer.

Jan 1, 1983

By M. Paul

"INTRODUCTION In 1990, the uranium production of SDAG Wismut in East Germany was stopped. 45 years of inconsiderate destructive exploitation had scarred both landscape and nature. With the “Wismut law” which came into force in December 1991, the Federal Republic took responsibility of the remediation of the legacies from former uranium ore mining and milling in Saxony and Thuringia. A unique opportunity turned out in order to remove environmental damage, to enhance the life quality of the local population, to shape new landscapes and to advance the economic restart. (1) The results of nearly 25 years of remediation activity are evidence that this opportunity was used at all former SDAG (Sowjetisch-Deutsche Aktien-gesellschaft) Wismut sites. The reference project “Wismut“ has evolved into a joint project of all parties involved and radiates beyond the affected regions. This is particularly reflected by the Know-how transfer starting from Wismut and the increasing activities for third parties abroad.WATER MANAGEMENT AT WISMUT REHABILITATION Within the Wismut project, water management and conventional technical water treatment are by far the most cost-intensive long-term tasks of the remediation programme. Over the medium term, there is no viable alternative to the operation of active systems to catch and treat contaminated mine waters at the Ronneburg, Schlema, Königstein, Pöhla, Seelingstädt and Helmsdorf sites. Based on the status quo, this paper outlines the key issues of the Wismut GmbH water management strategy over the medium and long term. It is focused primarily on achieving protection goals for potentially impacted water bodies in the surroundings of Wismut sites and on optimising associated remediation expenditures as well as on creating the prerequisites for achieving low post-remedial care and maintenance or walk-away system status over the long term. (2) The applied mining practices during the active SDAG Wismut period have not been up to the high standards of modern mining operations and their requirement to leave former production premises and deposited residues in a condition that was not only physically but also chemically stable. Rather the emission of mine and seepage waters laden with high acidity, metal and salt content is a frequent corollary and difficult legacy of historic mining and processing operations (4, 5). As a consequence, the control or mitigation, respectively, of environmental impacts associated with contaminated mine waters ties up enormous public resources worldwide (6, 7)."

Jan 1, 2016

"In addition to outstanding technical sessions and networking opportunities, the SME Annual Conference and Expo offers attendees a chance to see the latest and greatest technology that the industry has to offer. The 2017 SME Annual Conference and Expo was no exception as 575 companies filled 756 booths from Feb. 19-22 in Denver, CO. The following is a look at some of the vendors that were on hand.AIL MiningThe Edge, featured by AIL Mining at the 2017 SME exhibit, is a four-flange structural liner designed to be an alternative to structural plate’s traditional lapped seams and to help mine operators build more efficiently and safely. It is ideal for creating underground structures, such as mine shafts, ventilation raises and escape ways. The Edge is available on SuperCor structural steel plate — 10 times stiffer and five times stronger than traditional steel liner plate. It facilitates curved structures, both horizontal and vertical, and eliminates the need for ring beams. It is ideal for remote sites. For added safety, structures can be assembled from the inside, and the leak-resistant structures can be dismantled and removed easily. Brackets can be attached to mine shafts or vent raises to support Alimak rails or climbers. Similarly, brackets or hangers can be attached to drifts or tunnels to support mine air, water or electrical utility services.ArcadisMining companies spent nearly $12 billion on water infrastructure worldwide in 2014, reflecting the industry’s heightened concern about environmental issues and social, regulatory and political risks.So, with an increasing focus on water reuse and recycling, mining companies must have effective water management plans that include sustainable solutions. Also, many water quality issues fall under both state and federal regulatory jurisdictions. To solve these problems, Arcadis provides comprehensive ground- and surfacewater technical support in a complex hydrogeologic setting. It can characterize the nature and extent of mine-related constituents in ground water and surface water, as well as the complex interactions between the two waters, and prepare the operational permits needed by mine and tailings facilities. As an example, Arcadis constructed a hydrogeologic and geochemical conceptual site model that improved site understanding for a molybdenum mine in the western United States that spanned several watersheds. It also provided technical support for permitting and compliance issues, allowing the mine to return to active production."

Jan 5, 2017

By Ravi Sahu

"In the global mining industry, there are those who seem resigned to the fact that the mining industry has always operated according to certain time-tested principles that don’t involve jumping on every new technological trend. Others expect that mines will soon have autonomous electric vehicles running around the clock. The truth lies somewhere in the middle. In business, as in life, that is usually the best path to follow.The instant access to people and information provided by 21st-century technology continues to push businesses in all industries toward greater efficiency and unheard-of levels of modernization. And in the world of mining, the embrace of advanced technology is all about managing risk.However, even in this age of digital information overload, some mine sites still require employees to physically download data from individual trucks to monitor payload data and inspect road conditions using a clipboard. What’s more baffling is that other mine sites still have no way of tracking tons moved at all.This isn’t due to a lack of innovation in the industry. Quite to the contrary, there is an abundance of new technology available that provides real-time monitoring of vehicle movements and tracks road conditions without the intervention of people. So why are owners reluctant to embrace advances in mining tech?Gauging the value of changeSurvey data has traditionally been captured by ground laser scans and LIDAR systems. A mine site surveyor would drive around the pit with a truck-mounted scanner to generate a point cloud. This process would be completed every few days and would take an entire day.The many cons of this method far outweigh the pros. First, it provides no visual data. If an operation has moved beyond the roller wheel and tape measure, visual pit models and LIDAR scans are typically completed once every six to 12 months by an aerial flyover, but such sporadic information gathering isn’t likely to result in the most actionable data. Moreover, given the high cost (in terms of both money and time), the numerous safety and liability issues, and the lack of flexibility in scheduling, manual processes are more trouble than they are worth.Overall, while miners are excellent operators who value innovation, their employers often try to outsource it or acquire innovators instead of investing in existing technology that can improve current operations. It is a never-ending dilemma:"

Jan 5, 2018

By Davar Abi-Zadeh, Cillian Brown, Deepak Kandra

"Grout backfill strategy for a particular subsurface concrete tunnel (~4.9km long, 3.5m in diameter, carrying 20” gas pipeline) was based on achieving 1:100 slope of the fill in order to progressively fill the tunnel, in a series of 350m section. Grout rheology, particularly its non-Newtonian and thixotropic behavior, determines the final fill slope for given backfill strategy. The objective of this study was to simulate the two-phase grout mix backfill process using Computational Fluid Dynamics (CFD) and determine the slope of the fill to validate and optimize the backfill strategy. Three dimensional CFD study showed that for a 500m long tunnel section with a single injection point of grout, given its rheology, it will likely keep flowing without filling the 500m section height wise. Design optimization for filling was carried out using two dimensional studies to make the backfill process “slope independent” by incorporating a 2.5m high bulkhead at ~1,000m. INTRODUCTION As part of a gas field development a 20” onshore gas pipeline is required from the landfall site to the processing terminal some 8km inland. At the landfall site the gas pipeline is routed in a ~5km underground tunnel underneath a bay. For operational reasons and planning consents as well as to mitigate environmental impact based on an environmental impact study, once the gas pipeline and the associated services and spares have been installed, the subsurface gas tunnel will be fully grouted. There will be no permanent access to the tunnel after construction is completed and the site compounds have been reinstated once works are complete. One of the key requirements is that “full grouting of the tunnel” is desired. The grouting material used is a non-Newtonian and thixotropic fluid mixture of bentonite, cement, plasticizer, retarder/stabilizer and water. The tunnel is filled progressively in 350m sections using a combination of existing and new pipework assuming the grout rheology will yield a fill slope of 1:100 in a 350m section. The proposed grouting system used one pump at the grouting compound to pump the grout into the tunnel using the existing tunneling pipework. For the longer runs a second booster pump was used in series to pump the grout to its final discharge location. The filling process is controlled via a system of flow meters, pressure transmitters and a tunnel CCTV system."

Jan 1, 2016

By Jung-Hum Lee, Young-Joon Lee, Eui-Joon Hong, Seon-Hong Kim, Chan-Dong Kim, Keon-Woong Jeong, Ki-Lim Kim

"Subsea tunnel needs to be built over 50km long to connect between nations and continents. However there are only 19 tunnels longer than 5km in Korea, and there is no history of constructing and operating a tunnel longer than 50km. As the concept of a subsea tunnel, which withstands high water pressure and has an extremely long length is completely different from that of a land tunnel, all kinds of the latest technologies for tunnel construction are required such as survey and analysis of geology, design and construction under high water pressure, ventilation and prevention of disasters within an ultra long tunnel. Therefore, this paper describes the determination of tunnel cross-section under a high speed railway, structural stability, ventilation and fire safety under construction and operation, etc. through the virtual project for the length of 108km subsea tunnel under high water pressure of maximum 20bars from Honam to Jeju island in Korea. 1. INTRODUCTION The Honam-Jeju virtual project is subsea tunnel project to link from Honam(land) to Jeju(island) extending the currently operating Honam high speed railway line, and the same express train(t=18, design speed 350km/h, total train length 200m) operating at Honam line is applied in this project. As Honam-Jeju site is approximately 80km in straight distance with 160m maximum depth, subsea tunnel project should determine the various issues such as air quality/ventilation, aerodynamics, temperature, drainage, fire & life safety, structural stability. Figure 1. is the plan of subsea tunnel, with be constructed using Shield TBM. This double tube-Single track is composed of cross passages (every 350m in general section and 40m in emergency station), service tunnel, pressure relief ducts (every 250m), cross-over tunnels, shafts and emergency stations. 2. ALIGNMENT AND SITE CONDITON This project is planned as an ultra long tunnel of total length more than 105km via existing islands between Honam and Jeju island because straight alignment requires an artificial island which has high cost and construction risk, by deep water depth, though this is the shortest distance (see Fig 2). Water depth and topography in project site is divided into two blocks by Chuja Island. In first block to Chuja Island, depth of the water is 40m on average and maximum 60m, which indicates gradual change of water depth relatively. Also, outcrop bedrock is widely distributed near island."

Jan 1, 2016

By William Gleason

"It has been more than 10 years since Montana Resources’ copper/molybdenum mine has had a lost-time injury at its site in Butte, MT. With more than 350 employees and an average production of about 15.5 Mt/a (17 million stpy), which includes 29.5 kt (65 million lbs) of copper and 4 kt (9 million lbs) of molybdenum, the mine’s journey to a decade of exemplary safety is an impressive feat that has required hard work, commitment and, most of all, leadership from every level of the operation.It has not always been an easy journey, nor has it been one without scrapes and bumps along the way, but it is one that has produced stellar results. Mike McGivern, vice president of human resources, and Pete Steilman, safety manager at the mine, spoke with Mining Engineering about how the operation transformed from a site that was accustomed to collecting citations for safety violations to one that is now collecting awards for its safety record.Simply put, Montana Resources has made safety a value and the people its top priority.The operations faced many predictable challenges in 2003, when the mine was being brought back online after three years of sitting in care-and-maintenance status. It had been shuttered in 2000 because of low commodity prices and high operating costs, and, in the three years that the mine was idled, the equipment became dilapidated, and some of it was no longer in compliance. Less than half of the workforce returned to the site for the restart, and the team was challenged with getting the gears turning again to produce copper and molybdenum. But the most daunting challenge of all of was keeping the workforce safe during the transition.In the first few years of operation the mine racked up citations from the U.S. Mine Safety and Health Administration (MSHA) at an alarming pace, so much so that in May 2006, Montana Resources received a letter from the MSHA District Office informing the company that the operation was being placed on the Potential Pattern of Violations list due to its excessive citation history and high rate of significant and substantial citations. It was clear that something significant had to be done to change the course of action at the mine."

Oct 1, 2019

By D. Royston

The use of large face angle shell lifter-liners in combination with wider lifter spacing has grown in recent years, especially in large SAG mills. The claimed benefits are reduced ball on liner impact, leading to increased liner lives and less ball breakage, and both reduced packing and improved ball-on-charge impact, leading to improved mill performance. This review covers available published data on several mill sites and aims to quantify the observed benefits.

Jan 1, 2003

The major stages in the life cycle of a tailings facility include site selection, impoundment de-sign and construction, operation and closure. Optimum management of these stages requires an integration of all legal, engineering and environmental aspects in order to improve safety and minimize future potential risks for humans and the environment. This paper discusses the main factors involved at each stage and focuses on the stability considerations of the impoundment facility.

Jan 1, 2002

By André Vervoort

The roof behaviour in room and pillar panels during the development of roadways and the subsequent pillar extraction was monitored underground and numerical simulations were conducted. For several underground sites, a satisfactory, correlation was found between underground measurements and three-dimensional numerical simulations using a boundary element code in the linear elastic domain. However, to simulate bed separation, and roof block collapses more complex models were required, of which examples are presented.

Jan 1, 1992

By Christopher Laughton, Michael P. Bruen

At Fermilab, a 4000-ft long underground complex has recently been constructed for a high-energy physics experiment. The complex is sited up to 350 ft, below grade principally in bedrock. The rock excavations were mined by TBM and drill and blast methods and supported by a combination of rock bolts, dowels and shotcrete. Water control was achieved using a combination of pre- and post-excavation grouting, drainage systems, drip shielding and air desiccation measures.

Jan 1, 2003