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By Guilherme L. M. G. Carvalho, Zachary T. Fleming

In a world of 2-dimensional design documents, envisioning and understanding 3-dimensional interferences for complex foundation construction scenarios can be challenging. Videos and computer models serve as 3-dimensional spatial aids but have drawbacks related to a fixed perspective. Augmented and virtual reality (AR/VR) provide new tools to communicate design challenges and improve construction planning. This paper provides a practical look at the basics of AR/VR systems and the tools available to the foundation design and construction industry by giving a high-level example of the technologies’ use in the design and delivery phases of a complex micropile installation project for the remediation of a dam foundation. Using these technologies, GEI was able to design and deliver a complex foundation remediation solution. AR/VR benefited regulators, and the client, to help understand the design concept, construction sequencing, and approach to overcoming installation challenges. Due to its user-friendly nature and less rigorous programming and hardware requirements, AR proved to be more useful than VR for this scenario. AR/VR will likely not replace videos and computer models; however, it can be a useful 3-dimensional visualization aid that complements the project delivery process and offers benefits that traditional methods cannot. INTRODUCTION Augmented and virtual reality is a promising and rapidly developing technology within the engineering and construction world. Like any rapidly developing new technology, the language describing it can be confusing and dynamic. To eliminate the confusion some definitions must be made. AR/ VR definitions The definitions of virtual reality (VR) and augmented reality (AR) for the purposes of this paper are as follows: VR is a computer-generated immersive environment that the user experiences within a digital 3- dimensional space (Satava, 1993)AR is a composite view created by superimposing digital objects into the user’s real-world view (Azuma, 1997). Often, VR is used in an office environment and allows the user to “visit” the digital site to review site planning, construction sequences, and interference geometry. AR can be utilized in both the office and onsite environments. Like VR, the in-office application for AR is commonly site planning. AR also can be utilized in the field for applications such as seeing through the ground to locate known existing obstructions like utilities, gas tanks, etc.

Jan 1, 2019

By Noreen Tarac, Pablo Forgoso, Philipp Schober

A multiple use storage facility building is being developed in the Philippines on a peninsula that was reclaimed in the 1990s without any soil treatment. The subsoil now consists of loose to medium dense silty sand underlain by a soft to medium stiff clay. A liquefaction assessment by analytical methods have shown that the loose to medium dense silty sand yields a high potential for liquefaction and lateral spreading during pthe design level seismic event. To mitigate the risk of liquefaction and lateral spreading, as well as assure the slope stability of the shoreline, a solution utilizing a combination of ground improvement techniques by means of a Mixed-In-Place (MIPTM) Lattice Grid Wall and Stone Columns was developed and successfully executed. For the detailed seismic design, a Finite Element 3D analysis was undertaken to simulate static and dynamic actions on the buttress wall. The liquefaction assessment and settlement calculation were carried out based on analytical design approaches. For the execution of the Lattice Grid Wall, the Mixed-In-Place (MIPTM) method developed by BAUER Spezialtiefbau GmbH was applied. The stone columns were installed using the Wet Top Feed method.

Sep 8, 2021

By Dan Brown

Improvements in construction equipment and techniques in recent years have made possible the use of drilled shaft foundations in diameters and lengths not previously considered practical or feasible. Many highway bridge and other structures are now routinely founded on drilled shafts which -are 8 to 12 feet in diameter and extending over 200 feet in depth below grade. There are unique challenges associated with constructing such large and deep cast-In-place foundations and engineers should be aware of the special needs associated with site investigation, construction specifications, material requirements, and quality assurance. This paper outlines a number of special considerations for these foundations, along with strategies that may be employed to improve the reliability and quality of large drilled shaft foundations.

May 11, 2007

By Larry A. Enloe

The 16-to-1 milling operation is Sunshine Mining Company's first new silver and gold producing facility. The 16-to-1 underground mine and mill are located approximately 64 km (40 miles) southwest of Tonopah, Nevada. Ore re- serves in the epithermal vein deposit are estimated at 0.91 Mt (one million st) of ore, at an average silver grade of 206 to 240 g/t (6 to 7 oz/st) and an average gold grade of 1.2 g/t (0.035 oz/st). The underground mine uses a large diameter blasthole stoping system of mining using highly mechanized rubber-tired equipment. The mill uses conventional cyanide leaching with countercurrent decantation and Merrill-Crowe precipitation. The mill start-up was in February 1982 resulting in the first pour of dore' in March 1982. The mill's present annual production is approximately 31.1 t (1.0 million oz) of silver and 264 kg (8500 oz) of gold.

Jan 1, 1984

By William P. Prof. Blake

WHEN we consider the efforts made in Europe to promote the physical and moral well-being of the working classes, the question is suggested whether in this country, where, theoretically, every man is peculiarly the arbiter of his own destiny, we may not be too prone to expect every man to take care of himself, and neglect to make those provisions for the welfare of the employed, demanded alike by enlightened economy and humanity. In the older countries, where the disproportion between capital and labor is greater, and the working classes are more dependent, their welfare largely occupies the attention of employers. The subject is involved in the problem of the just relations of capital and labor, and we are rapidly approaching the time, if we have not already reached it, when a generous paternal interest in the welfare of the employed should be more generally manifested. It is a subject which is of special importance to mine-owners and engineers in this country, especially to those located in the coal regions. My own attention has been particularly directed to it by a visit made to the Hassard collieries, a few miles from Liege, Belgium, under the direction of M. Andrimont. This celebrated engineer has established a comfortable home for the miners near the mouth of the shaft of the mine. It has been highly successful and beneficent in its results, and may to a great degree be regarded as a, model for such undertakings. It is known as "Hotel Louise," this being the name of Madame d'Andrimont, who laid the corner-stone of the building April 4th, 1871. The structure is of brick, upon three sides of a square, and

Jan 1, 1875

By William P. Blake

When we consider the efforts made in Europe to promote the physical and moral well-being of the working classes, the question is suggested whether in this country, where, theoretically, every man is peculiarly the arbiter of his own destiny, we may not be too prone to expect every man to take care of himself, and neglect to make those provisions for the welfare of the employed, demanded alike by enlightened economy and humanity. In the older countries, where the disproportion between capital and labor is greater, and the working classes are more dependent, their welfare largely occupies the attention of employers. The subject is involved in the problem of the just relations of capital and labor, and we are rapidly approaching the time, if we have not already reached it, when a generous paternal interest in the welfare of the employed should be more generally manifested. It is a subject which is of special importance to mine-owners and engineers in this country, especially to those located in the coal regions. My own attention has been particularly directed to it by a visit made to the Hassard collieries, a few miles from Liège, Belgium, under the direction of M. Andrimont. This celebrated engineer has established a comfortable home for the miners near the mouth of the shaft of the mine. It has been highly successful and beneficent in its results, and may to a great degree be regarded as a model for such undertakings. It is known as ((Hotel Louise," this being the name of Madame d' Andrimont, who laid the corner-stone of the building April 4th, 1871. The structure is of brick, upon three sides of a square, and

By D Horacek, I K. Sheppard

Ok Tedi is in a period of transition. By 2008 mill feed will consist of higher levels of high-grade but metallurgically challenging skarn ores. Additionally, the Taranaki pit will start production in 2008 along with the start-up of a new pyrite concentrator. Taranaki ores are very high in sulfur. Sulfur is captured in a pyrite concentrate prior to tailing entering the Ok Tedi River. These and other complex scheduling issues will need to be resolved over a critical three-year period. With these requirements in mind, Ok Tedi contracted AMC Consultants to develop a custom version of the Life of Business Optimisation System (LOBOS¬) to assist medium-term production scheduling at Ok Tedi. LOBOS utilities enable Ok Tedi planning engineers to:import polygon-based reserve data (Blast Masters) from MineSightÆs Interactive Planning Tools (IP Tools); graphically construct block sequencing and material flow constraints; edit constraints defining standard scheduling, processing and financial relationships; define dump and stockpile attributes; and assign capacities to production systems, plants, dumps and stockpiles. LOBOS converts Ok TediÆs production scenario into a mixed integer program (MIP) and submits the resulting model to IlogÆs Cplex MIP Solver. The Solver seeks an optimal production schedule that maximises net revenue per mill hour while meeting all constraints. This paper introduces Ok Tedi and its production requirements and relates these requirements to the facilities developed for an Ok Tedi version of LOBOS.

Jan 1, 2007

By Alessandro Molinari

In recent times, coke oven machines are acquiring a more prominent role in the coke making process. Apart from the traditional handling of the coal and coke flow, nowadays these machines are also deeply involved in all environmental and process control aspects. Paul Wurth coke oven machines have been developed by Schalke to meet the most recent requirements in terms of emissions control, automation, instrumentation, operability and maintainability. In CSP, Ceará, the new coke making plant represents the status of the art of the technologies applied to the whole coking process; starting from the Coke Oven Batteries and the Gas Treatment Plant developed by Paul Wurth up to the Coke Machines supplied by Schalker Eisenhütte, whose technology is now part of Paul Wurth coke making products portfolio. Present paper describes the plant configuration focusing on Coke Oven Machines and the key factors which are guarantying the success of the project.

Aug 16, 2017

By Jack Taggart, Chris Barker

Pile load testing strategies for large infrastructure projects and multi-phase building developments have historically justified cost and programme benefits for undertaking advance preliminary and working pile load testing. However, more recently piling and pile load testing strategies have included assessment of the embodied carbon to understand and present the carbon savings that can also be achieved. This paper gives an overview of the factors contributing to carbon and emissions in the construction of bored pile foundations and presents the methodology taken in assessing embodied carbon as part of the pile load testing strategy for a multi-phased building development in London. Potential embodied carbon savings for various bored pile types and load testing strategies are discussed alongside alternatives and other considerations including pile re-use and carbon offsetting to inform continual improvement for future projects.

May 1, 2022

By Luca Pingue, Regine Jagow-Klaff, Franco Muratore, Carlandrea Albonico, Damiano Frontini, Rudolf Wernecké

This paper describes an artificial ground freezing (AGF) application carried out to ensure both watertightness and structural support for the safe excavation of four cross passages of the Forrestfield Airport Link (FAL) project in Perth. The line will deliver 8.5 km extension of the existing urban rail network connecting the growing eastern suburbs of Perth with the existing suburban rail network. The proposed soil improvement technique is adopted as a smart alternative to jet grouting from the surface since the use of heavy equipment with long vertical mast was not allowed due to the line underpassing an airport in operation. In this paper, details of the challenges and lessons learned during both design and construction phases are given. Furthermore, it is described the geometry and the installation of freeze pipes in presence of a massive steel frame, ventilation system and slurry pipes of the tunnel boring machine (TBM) in operation. It is also illustrated the web monitoring system to allow key personnel to follow in real time the development of soil temperatures, tunnel convergences and ground surface deformations as well as changes in the interaction between international parties involved due to the COVID-19 pandemic.

May 1, 2022

By AIME AIME

MESSRS. BURT and Shockley and others have been for three years urging upon the Institute the matter of simplified spelling. The Institute endeavors to be progressive in the matter of spelling and. is in cooperation with the national body which has this in hand and which has its principal office in New York. Our spellings are changed as fast as-good usage will permit (so it seems to the Board of Directors) and the national body, which is the real representative of the simplified spelling interests, deems that the Institute is making real progress, although not quite as fast as extremists would wish. In January, 1919, Mr. Shockley sent out letter ballots which created a misconception in the minds of many members, who received the impression that the communications came from the Institute instead of from a small group of members. As a result of this propaganda 163 proposal-ballots were sent in to the Institute divided as follows: Yes ?114 No ?20 Negative letters ?9 Split ballots ?20 Total ?163 The total membership at this time was about 7200. The disgusted members would not vote.

Jan 1, 1920

By Hallet R. Robbins

KOREA, the ancient " Hermit Kingdom," is a peninsula jutting out from the coast of eastern Asia. By the natives it is called " Chosen," which, translated, means " Land of the Morning Calm." It lies between the Yellow sea and the Sea of Japan. On the north it is separated from Manchuria and the Russian province of Primorsk by the Yalu and Tiumen rivers ; on the south the Korean straits interpose a rough voyage of 120 miles to the nearest point in Japan. The entire country is situated between the parallels of 34° and 42° N. latitude. The surface of the country is made up of successive ranges of unglaciated mountains, separated by narrow, fertile, and more or less densely populated, valleys. Through all the obscure centuries of its history, Korea has succeeded in maintaining a monastic seclusion, over which, from time immemorial until the late Chino-Japanese war in 1894, China exercised a shadowy sovereignty. Although Korea had been forced into slight foreign contact previously, her first foreign treaty was signed with Japan in 1876. Under the restraining guardianship of China, the Japanese treaty bore but insignificant innovations for Korea; but when, in 1883, a treaty was made with the United States, the first of the western nations, a decade after the American gunboats, under Commodore Rodgers and Lieutenant Schley, forced their way up the Salee river, shooting daylight through the ancient walls and fastnesses, Korea awoke from her sleep of 4,000 years. The Korean peninsula suddenly became the arena where rival nations' enterprises and individuals met in fiercest conflict. Out of this struggle grew two singularly successful American

Jan 7, 1908

By Rachael M. Fischer, Daniel J. Woeste, Terence P. Holman

"A new 50 MW biomass renewable energy power plant was planned for construction in southwestern Georgia. The original foundation design consisted of very conservatively designed H-pile groups with vertical and battered piles to carry the axial and lateral loads. The authors conducted a testing program to value-engineer the foundations with the goals of increasing the working axial pile resistance and reducing or eliminating battered piles. Seven test piles were installed and dynamically monitored with a Pile Driving Analyzer (PDA). Two lateral load tests and one tension load test were conducted. The results of our testing program allowed the project team to: (i) increase working pile resistances by factors of 1.5 to 2, reducing the total number of piles by more than 30%, (ii) eliminate the battered piles, and (iii) lessen overall project risk. Poor communication and documentation in a critical area of the site required some piles to be spliced and re-driven after additional PDA testing, establishment of new driving criteria, and consideration of longterm soil setup. This case study emphasizes the economic and risk reduction benefits of a design phase testing program, and the need for consistent communication between parties in the field.INTRODUCTIONA new 50 MW biomass renewable energy power plant (Plant) was planned and constructed in southwestern Georgia. The Plant converts clean wood-based and paper-based waste from existing forestry and pulp operations, waste timber, and maintenance operations into steam that is used by an adjacent manufacturing facility. The Plant also generates electric power with limited greenhouse or particulate emissions for use by a local utility provider.The project site (Site) is located in Dougherty County, in the Coastal Plain physiographic province of Georgia; an area of known karstic activity. Specifically, the Site is underlain at depths of 30 to 45 ft by the Ocala Formation, a light-colored fossiliferous limestone of the Eocene era. According to Watson (1981), the Ocala Formation is 125 to 200 ft thick in the vicinity of the Site and increases in thickness to the southeast. Due to differential weathering, this formation is characterized by an irregular upper surface that transitions from sandy clay/clayey sand into a dense to very dense silt and fine sand locally referred to as limestone. This subsurface stratum is most relevant to the foundation design of the Plant."

Jan 1, 2016

By R. K. Sinha, B. S. Choudhary, Desh Deepak, A. K. Mishra, Hemant Agrawal, Shankar Kumar

There are several methods (empirical, statistical, and machine learning tools) to calculate blast-induced ground vibration. Still, due to complications in the blasting procedure, under varying blasting loads and strata conditions, it is not easy to predict and simulate blast vibration precisely. Therefore, a study was conducted to simulate the field blast data in Ansys software using explicit dynamics. For this study, monitoring of ground vibration for 20 single hole blasts was carried out. The density of emulsion explosives was in the range of 0.9 to 1.15 g/cc. In the laboratory, rock properties were determined from the rock sample collected from the mine site before blasting. The in-hole velocity of detonation (VoD) and the density of the emulsion explosive were also determined. These parameters were used for numerical analysis to know the ground vibrations at specified points. The results of ground vibration predicted by the model are validated using field data.

By Paul M. Tyler

Hafnium appears to be among the more abundant of the newly discovered elements . Though quite widely distributed in nature , its compounds chemically so resembled those of zirconium , its sister element , that it escaped detection until 1923 , when Coster and Hevesy announced the discovery of the element , to which they gave the name of " hafnium " , from Hafniae , the Latin name for Copenhagen , where their research work was performed . Hafnium has so far been found only as a minor constituent of zirconium minerals . Zirconium as an element was discovered more than 140 years ago , but only a few unimportant uses were found for the metal or its compounds until some 18 years ago ; it is still classed among the rarer commercial metals . It is not surprising , therefore , that hafnium has not yet found a definite place for itself in industry . Nevertheless it has commanded a considerable interest among scientists ; and in 1930 some 70 grams of perfectly pure oxide of hafnium were prepared in Europe . A commercial future for hafnium is already glimpsed in the radio industry , and its high melting point and electronic emissivity have already led to the taking out of patents for its use in radio tubes and incandescent electric lamp filaments and for the cathode surfaces of devices such as X- ray tubes and rectifiers .

Apr 1, 1931

By E. P. Youngman

The basic mining law of French Morocco is the Edict of 1914, "Danir of Jamary 19, 1914, for the Regulation of Mineral Prospecting and Exploitation in the Zone of the French Protectorate of the Cherifien Empire," which, as the preamble states, was promulgated at the instance of the Director General of Public Works, in consideration of the fact that mines constitute one of the sources of wealth of the Empire. According to a consular report, dated May 18, 1923, by Bradford, men- tioned above, the mining industry of that country, aside from the exploitation of the extensive phosphate deposits, can scarcely be said to exist, but the potential field for mining is promising. However, no large-scale exploitation of the mineral wealth of French Morocco can be hoped for until there is complete pacification of large areas that are still in an unsubdued state or until adequate transportation facilities, scientific prospecting, and large investments of cap- ital are assured. An edict in 1920 (Dahir of January 27, 1920) modified the law mentioned above by declaring the prospecting for and the exploitation of phosphates to be exclusively reserved to the Government. The Dahir o. August 7, 1920, announced the creation of the Cherifien Phosphate Office (Office. Cherifien des Phosphates), a State monopoly charged with the exploration, management, and exploitation of the phosphates of Morocco.

May 1, 1930

By GRANT COLLIGAN, BROCK O’KELLEY, Corby Anderson

With the world’s ever-expanding push to expand technological capabilities, the need for specialized materials including rare earth elements has exploded. One source found in the USA is bastnaesite, a rare earth bearing fluorocarbonate mineral, currently mined at the Mountain Pass Mine in California. To increase production, it is essential to optimize existing processes and create new ones to better utilize current resources. Therefore, a US Department of Energy Critical Materials Institute sponsored research program was carried out at the Kroll Institute for Extractive Metallurgy to expand the fundamental understanding of the industrial bastnaesite concentrate leaching system. With the help of prior knowledge, thermodynamic calculations and design of experimentation based lab testing, a novel single-stage hydrochloric leach system was created to optimize the rare earth extraction from bastnaesite. Historically, the existing industrial process has utilized a two-stage leach system involving a high-temperature hydrochloric acid leach with liquid solid separations followed by a caustic crack stage of the leach residues. A series of single-stage leach experiments were run by reacting locked cycle flotation concentrates with hydrochloric acid to test common leaching parameters. The results of these patent pending single-stage tests have shown rare earth recoveries significantly higher than reported recoveries of historic two-stage caustic crack processes, all while decreasing the equipment required and the type and amount of reagents needed.

Jan 31, 2022

By Rainer Hüsken

Over the last decades long BOF campaign lives have successfully been established due to improved quality of the refractory material and due to intensive use of slag splashing. On the other hand, steelmakers are more and more faced with elevated phosphorous contents in the hot metal. This phenomenon is a global tendency caused by the increasing pressure to utilize cheaper iron ore sources. In India, iron ore sources have traditionally elevated phosphorous contents. The phosphorous removal challenge calls for using bottom stirring at the BOF converters, as these combined technology of top oxygen blowing and inert gas stirring through the bottom, helps significantly to improve bath mixing and thus in shifting the process towards the optimum metallurgical equilibrium conditions. All this is common knowledge and daily business in the steelmaking shops all over world. Unfortunately, focusing on a long BOF refractory campaign by means of slag splashing and maintaining optimum conditions for high efficient bottom stirring are naturally conflictive aims. Applying slag splashing causes unavoidable bottom built-up which in turn covers or even blocks the bottom tuyeres. Most of the steelmaking shops today are either operating slag splashing without bottom stirring or bottom stirring without slag splashing. Some are trying slag splashing with bottom stirring but mostly only for a certain short period of the whole campaign. Baoshan Meishan Steel is an integrated steel plant, located in Nanjing (China). The plant is operating two BOF shops (3x 150t and 2x 250t), producing various steel grades. Because of the iron ore source used, the hot metal phosphorous content is rather high with up to 2,000 ppm. In order to achieve low phosphorous contents in the molten steel below 200 ppm, Meishan uses the TBM (Thyssen Bottom Metallurgy) bottom stirring technology in both of their steel plants, successfully applying slag splashing and efficient bottom stirring for campaigns up to 10,000 heats. This paper describes the operation procedures, strategies, and the maintenance concept established at Meishan Steel which is suitable to meet both conflicting targets at the same time.

Jul 30, 2018

By Hongling Wang, DI WU, Shuai Li, Hui Shu

Isothermal reduction experiments on carbon-bearing pellets of copper slag were investigated by the thermogravimetric method with biomass carbon as a reducing agent. The results indicated that the reduction process of copper slag‑biomass composite pellets was dominated by gas phase diffusion, and the apparent activation energy was 88.44 kJ/mol. In the temperature range from 1000 to 1200 °C, the metallization rate of pellets increased with increasing temperature, and the maximum metallization rate was 78.4%. The optimal reduction temperature of CSBCP (copper slag-biomass composite pellets) was 1200 °C.

Nov 23, 2022

By G. van Eck, H. Smit, L. Meyer

The Cook Islands (CI) possesses within its Exclusive Economic Zone (EEZ) a massive field of polymetallic nodules representing one of the world’s largest undeveloped cobalt deposits, along with large quantities of other metals critical to achieving global energy transition targets. In February of 2022 the Seabed Minerals Authority (SBMA) of the CI granted Moana Minerals a license to conduct our nodule exploration program. This paper describes how Moana Minerals chose to approach conducting exploration activities, one of the greatest challenges to Deep Sea Mining (DSM) development and the securing of the social license to advance to eventual mining of the resources, in an unconventional manner. The remote location of the project poses logistical challenges in mobilizing to and operating in the region and is a significant cost driver. Historically, exploration campaigns mobilized large vessels from mainland Europe, the Americas, and Asia as this model works well when contemplating long duration and widely temporally spaced campaigns without the need to revisit. Moana Minerals, when considering these challenges determined a multi-year deep sea mining (DSM) exploration program conducted in such a remote location can be better optimized by the deployment of a smaller yet highly capable “exploration optimized” vessel that is dedicated to the task and is based full time in the Cook Islands. INTRODUCTION The paper describes the challenges of exploration in remote regions including the South Pacific, and how an unconventional consideration of the problem led to the solution. Completion of an Environmental and Social Impact Assessment begins with a detailed environmental scoping study, resource update sampling requirements, and engineering data and sample requirements, which identifies the exploration goals of the project and technology needed to accomplish those goals. The method walks the reader through vessel and technology selection, discusses the challenges of equipment selection considering size and capability, describes the final arrangement, and provides results from the initial exploration campaigns. We followed the project from conception through the shipyard conversion, mobilization, and initial operations in the Cook Islands. The result shows how a smaller vessel with limited budget makes a large impact on the exploration capabilities in the region while building public trust. The Anuanua Moana is the first dedicated deep sea minerals exploration vessel modified with a suite of technologies that allow it to compete technically with existing ships but operate locally in the smaller ports of the South Pacific. The unique combination of size and technical capability gives the Anuanua Moana advantages over other vessels. This paper shows the importance of the Anuanua Moana in the development of offshore exploration strategies in the emerging deep sea minerals space.

Feb 22, 2026