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By P. S. Miller, S. H. Ash

EXTENSIVE and diversified resources justify large populations and great industries. To carry on the business of commerce and meet the demands of large populations, the utilization of tunnels in some form for transportation purposes constitutes an important link in modern civilization. The driving of tunnels has been appropriated by the tunneling branch of the heavy-construction industry, and the progressive steps taken by modern tunnel builders were not even dreamed of 50 years ago. Great strides have been made toward more rapid progress in tunneling in the United States during the past 10 years. Tunneling consists of a definite cycle of operations developed from ideas that are crystallized and translated into action programs through various engineering phases that begin with the first preliminary survey and do not end until the job is completed. Once the line of the bore is established and a time set for the completion of the work, the face must advance according to estimates prepared before the work commences. This schedule must be followed in regular sequence from the moment the drills start against a new face of rock until they are ready again to drill the succeeding face, constituting a round.1 Mining is largely tunneling carried on under conditions often more inherently hazardous than actual tunnel construction, but for various reasons1 tunneling is more hazardous than mining in any branch of the mineral industry, On the other hand, obstacles are sometimes encountered in heavy-construction tunneling projects that when met in mining enterprises do not offer comparable tasks to avoid or overcome them. One of these is the existence of water under high pressures. In mining enterprises, various alternatives offer a solution in driving a tunnel, even to the extent of its discontinuance or the abandonment of the mine, but a "construction" tunnel usually must go forward because some important project depends largely if not entirely upon it. This paper describes an unusual method of driving a water-supply tunnel through rock carrying water under pressures and conditions that did not permit the use of ordinary tunneling methods. THE DELAWARE AQUEDUCT The new Delaware aqueduct is a Manhattan project of some magnitude; when completed, it will contain what probably will be, for some time to come, the longest tunnel in the world. Various features in its construction are currently described in the trade journals of the construction industry, and informative engineering details are given in the Delaware Water Supply News, published twice a month by the Board of Water Supply of the City of New York. Work was begun on this project on March 24, 1937. The tunnel will convey water from reservoirs at the headwaters of the Delaware River to the City of New York.

Jan 1, 1942

By Jim Rix, Ken Been, Nihal Bohra, Anthony Rice, Juan Lopez

"A temporary bridge, supported on steel pipe piles, was built to expedite the construction of a breakwater structure off the western coast of Peru. The bridge provided access for dump trucks to the breakwater across a 342 m (1122 ft.) wide navigation channel from a liquefied natural gas (LNG) loading facility, at the end of a 1.3 km (0.82 miles) long permanent trestle, in 15 m (50 ft.) water depth. After the completion of the breakwater, the temporary bridge was removed, and the piles were extracted approximately one year after the initial driving. The bridge deck was typically supported on pairs of 914.4 mm (3 ft.) diameter, 18 mm (0.708 inch) wall steel pipe piles spaced at 7.5 m (24.6 ft.) across the bridge width and 18 m (60 ft.) along the bridge length. In an attempt to reduce the driven pile embedment, an inner closure plate was installed at 2.7 to 7 m (9 to 23 ft.) from the pile toe to force closed-end behavior. The piles were designed to carry 3400 kN (383 tons) axial compression load, and a minimum of 8 m (26 ft.) embedment was specified to provide sufficient resistance to the lateral loads.The subsurface conditions consisted of cemented conglomerate of sand, gravel, pebbles and some boulders, locally known as the Cañete Formation. The driven pile embedment varied widely, between 8 to 24 m (26 to 79 ft.). A significant portion of each pile was above the seabed, passing through seawater and up to the bridge deck, and was therefore unsupported. The extraction of the piles was challenging due to the subsurface conditions, presence of significant water column, pile weight, and the inner closure plate. Several different approaches were attempted before the piles could be successfully extracted. This paper summarizes the difficulties encountered and observations made during the driving and extraction of these piles."

Jan 1, 2017

By Nihal Bohra

A temporary bridge, supported on steel pipe piles, was built to expedite the construction of a breakwater structure off the western coast of Peru. The bridge provided access for dump trucks to the breakwater across a 342 m (1122 ft.) wide navigation channel from a liquefied natural gas (LNG) loading facility, at the end of a 1.3 km (0.82 miles) long permanent trestle, in 15 m (50 ft.) water depth. After the completion of the breakwater, the temporary bridge was removed, and the piles were extracted approximately one year after the initial driving. The bridge deck was typically supported on pairs of 914.4 mm (3 ft.) diameter, 18 mm (0.708 inch) wall steel pipe piles spaced at 7.5 m (24.6 ft.) across the bridge width and 18 m (60 ft.) along the bridge length. In an attempt to reduce the driven pile embedment, an inner closure plate was installed at 2.7 to 7 m (9 to 23 ft.) from the pile toe to force closed-end behavior. The piles were designed to carry 3400 kN (383 tons) axial compression load, and a minimum of 8 m (26 ft.) embedment was specified to provide sufficient resistance to the lateral loads. The subsurface conditions consisted of cemented conglomerate of sand, gravel, pebbles and some boulders, locally known as the Cañete Formation. The driven pile embedment varied widely, between 8 to 24 m (26 to 79 ft.). A significant portion of each pile was above the seabed, passing through seawater and up to the bridge deck, and was therefore unsupported. The extraction of the piles was challenging due to the subsurface conditions, presence of significant water column, pile weight, and the inner closure plate. Several different approaches were attempted before the piles could be successfully extracted. This paper summarizes the difficulties encountered and observations made during the driving and extraction of these piles.

By Lucien Weber

In the Shanghai area, the soil conditions are such that bearing piles have become an essential foundation part of the new highrise buildings. In order to reduce the settlements under the high working loads of about 2300 kN/pile, the Chinese building authorities require the pile tip to penetrate into the compact sand layer, situated at approx. 60-70 m depth. No H-piles have yet been tested under these conditions in Shanghai. This paper describes the driving of 8 H-bearing piles with 4 different shapes and with lengths varying from 45 to 75 m. Dynamic measurements are performed during driving and after a wait time of approx. 40 hours in order to assess the change in bearing capacity in function of time and in order to get an idea about the resistance distribution along the piles by using a stress wave analysis program (CAPWAP). One pile is equipped with channels between the flanges for executing verticality measurements with an inclinometer. However, this test has not yet been performed. One month after driving, two piles of 75 m length are statically loaded both in vertical and in horizontal directions.

Jan 1, 1987

By P. Holman

I would like to start this paper by looking back about twenty years to see where we have been in the mining industry. We will also look forward a bit and talk about what lies ahead. Here is what has happened to the world economy since the 1970s. Economic growth was strong in the early 70s, but slipped into a recession in the middle of the decade. Then, after a fairly decent recovery recession struck again in the early 80s and since then growth has been rather sporadic. All in all, it has been a real roller coaster ride. There will continue to be plenty of ups and downs in the world economy in the future.

Jan 1, 1993

By S. T. Murray

The European industrial minerals industry and its markets are largely self-sufficient. The companies who are members of the Industrial Minerals Association (IMA-Europe) number around 150 contributing 5 billion Euros to the EU?s GDP and range in size from global publicly quoted corporations to small family owned private companies. Their means and capability to implement sustainable development vary considerably. However the leading companies provide an excellent set of best practices, which IMA as a trade association with recognised core competencies in the field of sustainable development is ideally placed to promulgate throughout its membership. As an active participant in the EU Voluntary Scheme for SDI reporting IMA is not only working to increase the level of response to the SDI questionnaire but is also developing with its members a new sustainable development charter which its members will voluntarily adopt as a guiding principle for their implementation of sustainable development This work will be a consultative process involving all IMA?s section members as well as other trade associations, NGOs and MEPs. Public awareness of the benefits of minerals and their contribution to sustainable development has been raised by IMA?s awareness campaign now being followed by a more targeted programme aimed at MEPs. Further work in the future will consider product stewardship and life-cycle analysis. IMA is already positioning itself with the help of its members to assimilate the minerals industry of the accession territories in the sustainable development process.

Jan 1, 2003

The current drill-and-blast method of tunnelling is cyclic and, for this reason above all others, has a future application potential which is lower than that of continuous methods. There is scope for progress in several facets of today's drill-and-blast tunnelling. But even if each of its unit operations and the synthesis of these were to be optimised, this conventional method will, in the long term, fail to be a serious competitor for tunnelboring machines (TBMs), roadheaders and the like. If its role in tunnelling is not to decline at an increasing rate, drill-and-blast will need to be transformed into a continuous system. Boring and cutting machines consume considerable energy (and expenditure) in creating rock fragments which are smaller than those required by muck-handling equipment. In this respect, blasting is more efficient. Mechanical methods are also less versatile and flexible and, when planning proceeds on a basis of meagre or inadequate geological data, cannot be costed as accurately. Currently, research gains for TBMs and roadheaders are greater than those for conventional tunnelling. If (as is likely) the disadvantages of mechanical methods continue to be reduced at a greater rate, the swing away from drilling and blasting will gain momentum.

Jan 1, 1987

By R Thompson, J Miedecke, D Handel, E Tomicek, D Tulloch

"The Mine Haul Road Optimisation Alliance (HROA) is a unique Australian industry–academia collaboration that has been developed to support mine haul road operators. The alliance integrates industry, end-user service providers and academic research expertise in mine haul road design, construction and operation to identify, quantify, implement and monitor the various equipment, materials and road management strategies and solutions required to drive haulage productivity improvements.Initially, a broad overview of the university–industry collaborative landscape is presented, following which the current situation in the Australian mining sector is reviewed both nationally, and on a country-wide basis internationally. This insight places into context the opportunity that strategic collaborations present, to drive productivity and efficiency in mining, while also delivering innovative technology solutions.Following an overview of the HROA collaborative structure, aims and objectives, it is shown how academia and industry collaborations can deliver a more robust and needs-driven solution to mine haul road design, performance and management, especially where integrated solutions are needed. Critically in this approach, implementation and monitoring data provided by industry and service providers alike form the foundation on which to develop research knowledge and innovation that is more responsive to the end-user requirements, typically represented by ‘early goals’ and practical, implementable solutions.The paper concludes with examples of how the alliance collaborations work in practice to deliver focused mine haul road research outcomes, together with the mechanisms used to ensure industry needs are met through end-user driven research solutions for enhanced operational performance.Citation:Handel, D, Miedecke, J, Thompson, R, Tomicek, E and Tulloch, D, 2016. Driving Haulage Productivity Improvements through Industry–Academia Collaboration, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 243–252 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By W. L. Saunders

(New Haven Meeting, February, 1909.) This paper deals specifically with heading-driving as distinguished from the broader term tunnel-driving. A heading is a pilot or path-finder for the main tunnel. Some headings are complete tunnels in themselves; that is, conditions at times warrant driving a heading the full diameter of the proposed tunnel. A tunnel 10 ft. in diameter might be driven to advantage through a single heading, provided the nature of the material admits, but it usually pays to drive rock tunnels of large diameter through the heading-and-bench system. Much de-pends upon the material, as in soft ground tunnels of much larger diameter are driven in a single heading. In mines, the tunnels, drifts, cross-cuts, adits, etc., are usually of small diameter, hence the driving of headings applies to completed tunnels in minim-work, except, of course, in cases like drainage-tunnels and main entries leading into coal-mines, where conditions call for tunnels of large diameter, approximating those driven for railway-service. In building aqueducts the tunnels are driven from 6 to 8 ft. in diameter up to 15 or 20 ft., while in railway-service the dimensions vary from 18 to 30 ft. in diameter. There is no department of rock-excavation so difficult as that of heading-driving. This work. also belongs to the most expensive class in rock-excavation. A heading is driven .directly in the solid. There are no lines of lesser resistance towards which to direct the energy of the blast, but. the material must be blown out by main force. The completion of the heading simplifies all the rest of the work of excavation. It is easy, for instance, to enlarge a heading either from above, below or oil the sides, by breaking towards the open face through holes approximately at right angles to the axis of the heading; or the enlargement sometimes takes place by holes driven outside

Apr 1, 1909

By J Taylor, M Smith, A Tunnadine, D Nikolakopoulos

As Olympic Dam rapidly expands into the Southern Mine Area (SMA) the Mine Geology team has concurrently ramped up underground diamond drilling to sustain rates of above 175 km/a. With >10 underground rigs double-shifting, traditional paper sections used for the management of drill programs were no longer optimal due to scale of operations. An opportunity was identified to modernise monitoring of all underground diamond drill programs, through the integration of logged copper sulfide estimates with Olympic Dam’s first-fully integrated deposit-scale geological model in Leapfrog Geo. This paper describes the transition within the Mine Geology team from reliance on 2D paper sections, towards near-real time 3D geological modelling for optimising end-of-hole decisions in the field. This transition was enabled by innovative database solutions informing locally constrained implicit models, limited by a distance buffer around active underground fan drilling. Due to the high volume of historic drilling, there were significant computational challenges with the implementation of daily production style implicit models at Olympic Dam and initial testing of regular updates to implicit gradeshells and sulfide domains required in excess of 12 hrs to run. The enabling solution was to optimise the interfaces between the AcQuire database, Deswik MDM and Leapfrog Geo to create a dynamic, streamlined workflow that was easily completed by Mine Geologists in accordance with daily production duties. Geologists are now building rapid implicit models for a range of variables from an integrated data set of logged sulfide estimates and existing assays, spatially constrained by 150 m buffers around active drilling using a unique drill fan identifier flagged during the planning phase. Once the live-implicit models are updated, they are exported for visualisation on field tablets to be used during logging and core checks at the start and end of every shift. To manage the risk of ‘going digital’ interpretation remains at the forefront of the drill section close-out process, with Mine Geologists critically reviewing the finished sections on a standardised template with new learnings wireframed and communicated to stakeholders. The Live Field Model has enabled a step-change in the geological effectiveness of diamond drilling, reducing over – and under-drilling ore-waste at Olympic Dam continuing to push drilling effectiveness towards 20 per cent of intercepts >2 per cent Cu. In addition, upside or risk identified during the proactive management of drilling execution can be rapidly capitalised or mitigated.

Mar 22, 2022

By H. W. Judges

A 16.5-kt/day underground molybdenum mine is being developed at Questa in Northern New Mexico by Molycorp, Inc., a wholly-owned subsidiary of Union Oil Company of California. Construction of the underground mine began in 1979, and first production is scheduled for early 1983. A gravity block caving method has been selected for mining the ore. Access to the mine will be through a service shaft, development shaft, and a conveyor decline. The shafts are being sunk under contract and the conveyor decline is being driven by Molycorp. The driving of the decline began in February, 1979 with a 10-man mining class. By the first of May, enough men had been trained to begin a continuous operation and by March 1, 1980 the face had reached the 1500 m mark. The heading is being driven with trackless rubber-tired equipment using a three-boom drill jumbo, 2.7 m3 LHD units and 7.3 m3 trucks. Ground support has been by rock bolts and wire mesh, followed by Fibercrete. A 16.5-kt/d underground molybdenum mine is being developed at Questa in northern New Mexico by Molycorp, Inc., a wholly-owned subsidiary of Union Oil Company of California. The new $200-million underground project will revitalize mining and milling activity at Questa, where small scale underground mining first began in 1920. Large scale open-pit mining was initiated in 1965 but now, because of the high stripping ratio, surface mining is being phased out. Construction of the underground mine began in 1979, and first production is scheduled for early 1983. The company expects full capacity - 9 Gg of molybdenum per year - to be reached in 1984.

Jan 1, 1980

By D. R. Shoemaker, H. W. Judges

A 16.5-kt/d underground molybdenum mine is being developed at Questa in northern New Mexico by Molycorp Inc., a wholly-owned subsidiary of Union Oil Company of California. The new $200-million underground project will revitalize mining and milling activity at Questa, where small scale underground mining first began in 1920. Large scale open-pit mining was initiated in 1965 but now, because of the high stripping ratio, surface mining is being phased out. Construction of the underground mine began in 1979, and first produc¬tion is scheduled for early 1983. The company expects full capacity-9 Gg of molybdenum per year-to be reached in 1984.

Jan 6, 1980

By D. M. Weinberg, S. R. Novascone, R. R. Reynolds, J. H. Cole, C. D. Christensen

The mechanical properties of the rocks surrounding an orbital vibrator alter the shape and amplitude of the vibrator’s orbit. Detecting these changes with driving point impedance measurements promises to reveal fractures and, possibly, identify the in situ stress state and significantly increase the depth that can be investigated. Our research emphasis has been on detecting vertical fractures through casing. Experimental and numerical results to date indicate that our new logging tool has excellent potential for determining both the vertical extent and azimuthal orientation of such fractures. Fracture and in situ stress orientations are useful in mine planning.

Jan 1, 2002

By S G. Walters

The minerals industry is facing a productivity and investment crisis. The ‘Millennium Super Cycle’ from 2003–2011 was an unprecedented period of growth and investment resulting in increased throughput and development of lower grade resources to meet demand. During the boom quantity became more important than quality with throughput the key metric. This was accompanied by a general trend of decreasing feed grades across all commodities that was offset with higher production volumes.Current industry perception is that feed grade depletion is an unavoidable consequence of ore deposit geology and mass mining technologies for increasingly mature mining operations. In typical crush-grind-float operations value recovery only takes place at ~1–200 micron particle size during flotation, ie 3–4 orders of magnitude size reduction compared to primary feed. For increasingly low-grade deposits the cost of energy and capital intensity required to process and reject low value material at micron scale drives poor productivity. An alternative is to deploy a range of coarse (~10–100 mm) separation and rejection technologies. Grade Engineering® is an integrated approach to coarse rejection that matches a suite of separation technologies to ore specific characteristics and compares the net value of rejecting low value components in current feed streams to existing mine plans.Coarse rejection can be used on size distributions ranging from run-of-mine (ROM) to semi-autogenous grinding (SAG) discharge. Grade Engineering® is based on five rock based ‘levers’ linked to combinations of screening, sensor-based sorting and heavy media separation. These involve exploitation of preferential grade deportment to specific size fractions during breakage: differential blasting to condition grade by size at bench scale; sensor based sorting at truck and conveyor scale; and differential particle density.Grade Engineering® is being developed and implemented by a consortium of over 30 mining companies, equipment suppliers and research organisations. Emerging results from collaborative site activities demonstrate potential for generating significant value, which can reverse the trend of declining productivity due to feed grade depletion.CITATION:Walters, S G, 2017. Driving productivity by increasing feed quality through application of innovative Grade Engineering® technologies, in Proceedings Tenth International Mining Geology Conference 2017, pp 263–274 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

A drive, 3,500 ft long, was planned to explore mineralization exposed by diamond drilling. A rate of advance of 150 ft per fortnight, approximately double previous Broken Hill rates, was required. Subsequent to the completion of this drive its extension for a further 6,200 ft was planned to provide a main haulage way along which ore could be transported from a newly acquired lease back to the main hoisting shaft, a total distance of 13,500 ft.This paper describes the working conditions, relationships, manning and costs, and gives details of the cycle and equipment used to achieve rates up to 170 ft per fortnight.OBJECTIVEDiamond drilling from the 1,000 ft level at the Delprat Shaft section had indicated that the zone of mineralization, about 150 ft wide, which had been explored on the 1,000 ft level for a length of 2,600 ft, continued downwards with a westerly dip. The drilling results showed that within this wide zone there were arrower lenses of mineralization of possibly payable grade (see composite plan, Fig. 1).Diamond drill holes of 2,000 ft and over, particularly through heavily sheared areas of sericite schist, had been found to be costly, slow, and inadequate in testing the potential and trends of these smaller concentrations of mineralization.It was therefore decided that an exploratory drive should be advanced from the northern limit of the 1,480 ft level into the western mineralization, and that from this drive diamond drill holes should be drilled at dose intervals to outline the ore.The 1,480 ft level was chosen for the following reasons.1. It had the greatest northerly reach of the accessible levels at No. 7 Shaft section below the 1,000 ft horizon and therefore would enable the test to be made most quickly.

Jan 1, 1965

By Victor L. Stevens

The Oso tunnel is one of three tunnels located on the San Juan-Chama Project in south-central Colorado. The purpose of the tunnel is to carry water from the upper San Juan watershed through the Continental Divide into the Rio Grande watershed. The Oso tunnel contract was awarded by the U.S. Bureau of Reclamation to a joint venture of Boyles Brothers Drilling Co., Gibbons & Reed Co., and Cimco in February 1966. The Oso tunnel is 26,660 ft long and has a rock section of 10 ft, 2 in. with a lined diameter of 8 ft circular. The main portion of the rock formation was in the Lewis shale. This formation is quite consistent in hardness and texture with exception of localized limestone concretions and sandy siltstone inclusions. The job was bid on the basis of using a James S. Robbins mole of the P221 series. The decision for using a mole was predicated on the geology and the experience of the same joint venture on the adjoining Azotea tunnel where a mole was successfully used. The Robbins P221 series mole is capable of cutting from 9 ft, 11 in. to a 10 ft, 7 in. diam without any major change. It is 40 ft long and weighs 60 tons. The cutting head has 22 disk-type cutters and one center pilot (standard 9 7/8 -in.) tricone bit. The head is powered by four 75 hp electric motors. Gripper pads at about the midway point on each side of the machine are pushed into the tunnel ribs and thrust-cylinders in front of each gripper apply pressure to the face as the head rotates. The regripping cycle is 3 ft and then the grippers are retracted and advanced. Each cutter on the perimeter of the head is followed by a bucket which scoops up the cut material, almost in the same manner as a water wheel, and dumps it into a conveyor situated along the top of the mole. The muck from the mole conveyor is dumped into a gantry-type conveyor. The gantry conveyor is 350 ft long and is pulled

Jan 1, 1970

By M McCurd, M Lynch, B H. Yin, S Mendoza, C W. Bumby, Y Iwasaki, B Rumsey

Iron and steel production is responsible for approximately 6.3 per cent of global anthropogenic CO2 emissions. Direct reduction of iron with hydrogen is a potential route for decarbonising the iron and steel industry. Extensive small-scale laboratory experiments have been performed to test the feasibility of hydrogen-direct reduction of iron ores sourced from diverse geographical locations. However, test results from the batch reduction of small-sample do not necessarily translate to continuous commercial-scale processes. Establishing a small-scale continuous test reactor for H2- DRI process is challenging, requiring substantial resources and investment. The limited availability of small-scale reactors that enable testing under relevant conditions has become a major obstacle for H2-DRI development, leaving a big gap between laboratory success and proof of commercial feasibility. Here, we report on the recent commissioning of a continuous counter-flow vertical shaft reactor, which has a processing capacity of 6 kg/hr iron ore pellets at up to 100 NL/min H2 flow. We believe this to currently be the largest H2-DRI facility in the Southern Hemisphere. In this talk, we will discuss the design and construction journey for this reactor, starting from the initial system design to the initial demonstration of H2 reduction of titanomagnetite ironsand pellets. This reactor now enables a range of research capacities, including the validation of laboratory results on a larger scale with practical operational variables, feasibility assessment of hydrogen direct reduction of different iron ores on a commercial scale; identification of scalability, sticking, and other potential issues before building a full-scale plant; and a viable solution for producing small-quantity DRIs for downstream melting investigations. Overall, this new research facility offers significant benefits for assisting the transformation of iron and steel production to a more sustainable and green industry.

Sep 18, 2023

By Chris Tattersall, Tomyuki Kudo, Peter Raleigh, Nestor Garavelli, Steve Redmond, Michael J. Lehnen

Twin bore running tunnels driven approximately 4,500 route feet by a Mitsubishi Heavy Industries (MHI) EPB Tunnel Boring Machine link the West Portal and East Portal on this complex Light Rail Project. One third along the way, the TBM arrives at the Beacon Hill Station which is the deepest underground “binocular” station of its kind in North America and then “walks-across” the station to be re-launched on the other side to complete the drive. This paper discusses briefly the layout and design considerations but then focuses more deeply on the approach by the Contractor to drive and supply the tunnel. The paper addresses the approach used to launch, re-launch and recover the TBM and touches briefly on muck volume control and monitoring plus settlement monitoring and the performance achieved. Also of interest is a unique solution to a difficult launch situation involving a secant pile tieback wall designed with several rows of double I-beam steel walers spanning the eye at the West Portal under the I-5 freeway.

Jan 1, 2007

Owing to the 'creeps' and consequent movements in the mines, followed by the recent fire in the southern workings, the whole of the orebody above the 800 ft. level is now very much crushed and broken. The same applies to the hanging wall or overwall coutrny, which has subsided towards the workings, so that for some years past all development work within the lode has had to be carried out with extreme care.The continual but slow subsidence of the overburden into the stopes necessitates a periodical renewal of all gangways in the lode, and, as the subsidence amounts to as much as 60 ft. in places, these new gangways must necessarily pass through the mullock-filling of old stopes in addition to broken ore. They at times pass into the broken ground of the hanging-wall for some distance, where the orebody has widened underneath by the original folding and puckering.

Jan 1, 1932

By Jose A. Gomez, Javad Sattarvand

Failures of tailings dams have been happening lately. Due to the lack of laws on particular design criteria and stability requirements related monitoring during construction and maintenance, they are thought to be more fragile than hydraulic dams. Monitoring the dam is therefore necessary to understand its current condition and guarantee its safety. The physical condition of the dam could be evaluated with the early identification of seepage. Additionally, due to their adaptability and capacity for high-resolution data collecting, UAVs are an excellent choice for efficiently covering the tailings dam site. UAVs may capture high-quality photos when equipped with a high-resolution RGB camera, thermal sensors, or multispectral sensors. When these sensors are paired with image processing and machine learning algorithms, the result is a reliable estimate of the dam condition.

Jun 25, 2023