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By Robert Drummond

Away back in the eighties of the last century, when Sir Charles, then Doctor, Tupper, was not only a prominent but a dominant figure in the political life of Nova Scotia, his opponents brought the railing accusation against him that he was the foremost of egotists because of his frequent use of the personal pronoun. I heard Tupper speak and had no sympathy with the railers, because I could not well see how the pronoun could be dispensed with without laying himself open to a charge of affectation. I shall make reference in what follows to incidents in which I have taken part, and shall be at no pains to dispense with the pronoun, even though thereby I lay my-self open to the charge of being a pupil of the deceased states-man. EVENTS LEADING UP TO THE ORGANIZATION OF THE PROVINCIAL WORKMEN'S ASSOCIATION The Springhill Mining Company began development work at Springhill in the early seventies of last century. So vigorously was the work prosecuted that in 18 7 4 two slopes, the east and the west, were in active operation, with a considerable. output, the east slope on occasional days producing 800 tons. The President of the Company, the late Senator McFarlane, was a Nova Scotian, the other directors were mainly merchants from St. John, N.B. From the first the enterprise was an .astonishing success, due in the greatest part to its geographical position, and in large part to the untiring vigilance of the directors, a majority of whom visited the collieries at short intervals, thereby keeping the manager, much of the time, on tenter hooks.

Jan 1, 1924

By A. Moyano

The development of the traditional converting process performed in a PeirceSmith or Hoboken converter is limited by the investment magnitude associated to the fulfillment of the environmental regulations. Thus, the continuous converting process rather than a conceptual process alternative is becoming a necessity for a smelter facing limited converting capacity and/or lacking of fulfillment of the environmental regulation with its maximum converting capacity. The objective of this paper is to present the progress of the Codelco continuous converting process evaluated at pilot-scale level when converting solid mattes or white metal into blister copper. These tests allowed for gathering of relevant data to be considered for a new stage of evaluating the Codelco continuous converting at industrial-scale test. The pilot-scale tests were done in a Teniente Converter pilot scale unit at the Codelco Norte Smelter. The results of processing solid copper mattes (65-75% Cu) and producing low sulfur content blister copper with production of a constant S02 gas concentration, and the production of liquid slag with low copper solubility was achieved and is discussed in the present paper.

Jan 1, 2007

By W. Blum

Progress made in improving the creep resistance of Mg alloys is reviewed with the emphasis on microstructural interpretation. Experimental results on the increase of creep strain with time at constant stress a measured for limited times and strains are displayed in a transparent form as creep rate-strain diagrams from which the minimum creep rate stress is safely derived. In addition, data on the thermal stress component a derived from high-precision a-reduction tests are reported. Within a simple statistical dislocation model these data allow one to quantify the relation between dislocation velocity v and a . In combination with structure evolution laws this relation serves as a basis for modeling the creep rate. New alloys have distinctly higher creep resistance than AZ91 where precipitation hardening plays a minor role. This is due to hardening by intermetallic phases which may form a continuous skeleton along the grain boundaries (e.g. Ca-alloyed AZ91) and/or submicron-sized precipitates within the grains (MRI230D, Mg-Zn-Ca alloys).

Jan 1, 2006

By B. MohammadSadeghi, S. Bakhshivash, M. Haghshenas, F. Rahimi

"Constrained groove pressing (CGP), as a severe plastic deformation (SPD) technique, is one of the applicable methods for sheet metal forming capable of producing ultra-fine grained materials (UFGMs). In CGP, processing and die design parameters can significantly affect the deformation response of sheet metal specimen. Having said this, in the present research the effects of die design variables and processing parameters (i.e. shear angle and friction) on the deformation behaviour of an Al-Mg-Si Alloy are studied thoroughly. Finite element analysis (FEA), was used to evaluate the effectiveness of mentioned parameters on the deformation homogeneity, strain distribution and pressing load variations. Also, mechanical properties of the deformed sample in term of micro-hardness was analyzed. It is observed that with increasing the shear angle, effective stress, strain and pressing load are enhanced. Moreover, by increasing the coefficient of friction, pressing load enhances. The color coded micro-hardness measurement showed a good agreement with the strain distribution obtained from FEA (higher hardness for the zones associated with higher shear plastic strain values).INTRODUCTIONWork hardening results in enhanced mechanical properties upon cycles of deformation (Hosford & Caddell, 2007). However, the formability of the processed products are affected by work hardening reducing the possibility of processing in subsequent deformation cycles. Therefore, many industrial processes cannot be performed on sheet metals to produce products with desired mechanical and physical properties (Valiev, Islamgaliev, & Alexandrov, 2000). Severe plastic deformation (SPD) is an effective grain refining technique which can impose large plastic strains through cold working on a metallic specimen (Bisadi, Rastgou, Payganeh, Zeynali, & Ghahremani, 2010). SPD techniques are mainly categorized into three types; sheet, bulk and tube forming. Among SPD sheet forming methods, Constrained Groove Pressing (CGP) (Shin, Park, Kim, & Park, 2002), Accumulative Roll Bonding (ARB) (Saito, Tsuji, Utsunomiya, Sakai, & Hong, 1998) and Repetitive Corrugation and Straightening (RCS) (Zhu, Lowe, Jiang, & Huang, 2001) possess potential applications in manufacturing industries."

Jan 1, 2016

By G. G. Bowser

PERUSAL of a list of present-day commercial explosives perhaps does not convey a full realization that there has been a great deal of improvement since the original dynamite was discovered nor that, in recent years, great developments have taken place in specialized explosives. This is true particularly of high-explosives for use in metalliferous mining or what is more commonly termed 'hard-rock' mining. Not many decades ago, only two or three types of explosive were avail-'able for commercial use. One was black blasting powder. Another was ordinary nitro-glycerin dynamite in various strengths. Black blasting powder remains with but very little change. Despite its ancient lineage, it is still with us as perhaps the sole explosive in use today which is almost identical in appearance, physical properties, and working ability or execution co the original. Which dynamite the story is different. Its evolution may be likened to that of the dog, nitro-glycerin as first discovered being the counterpart of the wild dog and, like it, dangerous and hard to control. The original dynamite as made by Nobel might then be considered as representing the first domesticaced species. This original dynamite, however, has been 'crossed with other bloods' until one sees now many distinct 'breeds' in the list. Present-day explosives still have the 'bark' and the 'bite', but with control and research have come many improvements; and types have been created which are specially adapted for particular kinds of work. We still have the direct descendant of Nobel's dynamite in the form of an improved nitro-glycerin dynamite. This C-I-L explosive, Polar Dynamite, is no longer the best type to use in the hunt for gold, silver, iron, and other metals. There have been developed other explosives more suitable for chat work. In Canada, such explosives are accomplishing this work effectively, not only where climatic conditions are moderate but through the rigours of our northern winters, with their sub-zero temperatures.

Jan 1, 1938

By John W. Bell

A FEW years ago the writer had the privilege of examining a piece of apparatus in the Forest Products Laboratory of McGill University which engaged his attention. The Forest Products Laboratory has an excellent installation of wood-grinding machinery, and the officials in charge were naturally interested in acquiring means for estimating the fineness of various wood grinds. The problem was referred to Dr. O. Maass ( l ). Dr. Maass designed a piece of equipment to measure the surface of a wood grind and derived an equation applicable in calculating its value, as follows : After inspecting this apparatus, the writer was disposed to believe that, with some modifications, Dr. Maass' ingenious idea might be utilized to measure the surface of mineral powders. Obviously, some difficulty would be found in maintaining an even suspension of mineral particles of high specific gravity compared to that of wood pulp. The writer will not bore the reader with a description of the various machines built and tried out. Some of these were satisfactory enough to obtain some valuable information, and to bring to light a difficulty which threatened to bring the investigation to an abrupt ending. For the mineral quartz, it was found that Kin the formula above stated was not a constant.

Jan 1, 1944

By M. Choy, A. Kadiayi, E. Magdzinski

"Design of engineering controls to limit occupational noise exposure rely on accurate calculation inputs. Sound in mines can carry considerable distances. Mine ventilation engineers rely on noise propagation calculations to estimate silencer performance criteria for key mine fan installations that are often in proximity to occupied areas of a mine and can remain in service for decades. The blasted and rockbolted walls of hard rock mining tunnels have unique acoustical properties. Underground testing in an operating metal mine in Sudbury, Canada was performed and results processed to characterize noise propagation in mines, with the goal of improving the accuracy of noise calculations.INTRODUCTIONAs mine operators continue to improve and promote workplace safety, addressing noise at fixed infrastructure locations is observed as increasingly common. Underground fans are important to consider in this context, as they are typically loud, in proximity to occupied and sensitive workplaces, and operate nearly continuously. Predicting noise propagation from ventilation fans within underground mines has long been a challenge, with few available resources documenting acoustical properties as calculation inputs. Other factors in addition to rock face absorption properties include tunnel geometry and distance from the fan, which play critical roles in characterizing the noise level at any given point away from the fan. By understanding and establishing methods to better predict noise dissipation along underground mining tunnels, engineers can design noise controls with a greater degree of precision and confidence to effectively protect workers from over exposure to noise.This paper investigates classical methods of predicting reverberant room and direct field noise propagation. These prediction methods are then compared to noise measurements taken within the Fraser Mine of Glencore’s Sudbury Integrated Nickel Operations (Sudbury INO) Measurements were taken at a depth of ~881 m (2,889 ft), along an ~300 m (984 ft) long blasted hard rock mining tunnel. The noise along the mine tunnel resulted from the intakes of two 900 kW (1,200 hp) ventilation fans with a combined exhaust capacity of 300 m3/s (630,000 cfm)."

Jan 1, 2019

By Raju S. Sagi

This paper deals primarily with the different types of drilling methods used by the Iron. Ore Company of Canada for sampling the soft and friable hematite-limonite (secondary) iron ore deposits found in the Scheferville area. The problems associated with drilling, sampling, sample handling and sample preparation. for chemical analysis of these ores are discussed. Systematic evaluation of the various drilling methods led to the selection of an integrated drilling system. This system consists of a rotary dual- tube - reverse-circulation drill, with tricone bit, polymer mud and mechanical sample splitter, The historic al development of this drilling system is described in detail, as are the equipment , sample flow and quality control checks carried out to obtain representative samples. This integrated drilling and sampling system has been used satisfactorily on a routine basis for determining the grade and tonnage of ore for the various deposits for the last five years (1972-76) in the Schefferville area.

Jan 1, 1977

By B. Burke

Magnesium and its alloys are attractive materials for use in automotive and aerospace applications because of the low density and good mechanical properties. However, difficulty in forming magnesium and the limited number of available commercial alloys limit their use. The present paper reviews the efforts to improve the attractiveness of magnesium through non-traditional processing, and presents preliminary results of current work on producing magnesium alloys via powder metallurgy P/M. P/M can be used to alleviate the formability problem through near-net-shape processing, and also allows unique chemical compositions that can lead to new alloys with novel properties. The feasibility of producing magnesium powder metallurgy products utilizing the industrially dominant process of mixed powder blending, uniaxial die compaction and controlled atmosphere sintering was investigated. An alloy composition based on the commercial Mg alloy AZ31 (3% Al, 1% Zn) was used to facilitate comparison to similar wrought products. The optimal processing conditions (compaction pressure, sintering time and temperature, and quenching temperature) were found to maximize sintered density and mechanical properties.

Jan 1, 2007

By S. Nakamura, M. Takaoka, Y. Mizuno, T. Kusakabe

"Mercury is produced as a byproduct from gold mines and, historically, has been transferred to recyclers and used for various industrial processes and products. However, under the Minamata Convention on Mercury, adopted in 2013,the intentional use of mercury in processes or products will be minimized in the world. Surplus elemental mercury should be treated as a hazardous waste and consequently, should be converted to a more stable chemical form for long-term storage or permanent disposal. A stabilization method has been developed to react mercury and sulfur using a planetary ball mill. The planetary ball mill can produce high-energy conditions and enable samples to react within a short period of time. A series of tests has been conducted to confirm that mercury sulfide can be produced using a bench scale machine with 2400 mL pot. Under a suitable experimental condition with 25 mm ball diameter, 30%of ball filling rate and 1.05 of molar ratio of S/Hg, a powdered mercury sulfide product was successfully obtained in 60 minutes. The leach ability and atmospheric emission from the product was extremely low. This stabilization method would contribute to an environmentally sound mercury management strategy for the gold industry.INTRODUCTIONDue to its unique physical and chemical properties, mercury has numerous applications, including in industry and medicine. However, mercury and its compounds are highly toxic. For example, in Japan, methyl mercury in waste water caused Minamata disease in the 1950s, which affected large numbers of people (Minamata Disease Municipal Museum, 2001). In recent years, environmental pollution caused by emissions and releases of mercury into the atmosphere, waterbody and land by various emission sources such as coal fire plants, artisanal and small-scale gold mining (ASGM), non-ferrous metal industries, waste incinerations etc. has also become a significant problem. To protect human health and the environment from anthropogenic emissions and releases of mercury and its compounds, the Minamata Convention on Mercury was adopted in 2013(UNEP, 2013)Because ground gold ore typically contains mercury at 0 to 100 ppm, mercury is often produced as a byproduct from gold mines (UNEP, 2016). In gold mining operations, mercury can be released from the ore by roasting or by leaching in cyanide solutions and recovery onto activated carbon. According to Yanget al. (2016), 85.1%of mercury in a concentrate was vaporized during a roasting process. Both processes finally discharge elemental mercury as a byproduct. In the USA, more than 100 ton of mercury was discharged from large-scale and industrial gold mining (Miller, 2004)."

Jan 1, 2017

By P. Clinton Milne

Uranium mines in Washington State include the producing Midnite and Sherwood mines and several mined-out deposits, the most productive of which was the Daybreak mine. The Midnite mine is generally classified as a hydrothermal deposit consisting of tabular orebodies in Precambrian pelitic and calcareous metasedimentary host rocks. The host rocks occur as roof pendants in a Cretaceous porphyritic quartz monzonite intrusive; the quartz monzonite averages 12 ppm U308 The uranium deposit appears to have undergone a complex genesis, involving a series of depositional and enrichment stages. The Sherwood uranium deposit, approximately 4 miles south of the Midnite mine, occurs near the bottom of a basal Late Cretaceous to Paleocene arkosic conglomerate. The conglomerate lies nonconformably on the porphyritic quartz monzonite that is associated with the Midnite deposit. The Sherwood and Midnite uranium deposits may have had a similar genetic history linked by a common uraniferous pluton source, ground-water action, and/or leaching of uranium-rich ash flows from now-eroded, overlying, Eocene volcanics. The Daybreak deposit, in northeastern Spokane County, consists entirely of secondary uranium mineralization (metaautunite) in a quartz monzonite pluton. Mineralization is confined to a low-angle fault zone and is most highly concentrated at the intersection of primary and secondary shears. Both hydrothermal and ground-water origins are feasible. Besides the Midnite-Sherwood area, 14 other areas in the western Okanogan Highlands physiographic province and Cascades region have favourable characteristics for uranium potential. Criteria include the existence of uranium occurrences, Tertiary basin sediments with intercalated volcanic and volcaniclastic rocks, favourable geochemical data, alkaline plutons associated with uranium occurrences or borders of Tertiary basins, and structural controls.

Jan 1, 1979

By Rick Coleman, Chelvan (Chevy) Veloo

"P.T. Freeport Indonesia's lrian Jaya Operation has been producing copper concentrate continuously since 1972. Numerous ore discoveries and five mill expansion programs have seen the initial milling rate of 7,200 MTPD escalate to the present rate of 125,000 MTPD, producing 2.5 million pounds of copper and 3,500 troy ounces of gold per day. The latest expansion, commissioned in February 1995, incorporates a 34 foot Semi- Autogenous Grinding (SAG) Mill, two 20'x30' Ball Mills, conventional roughing, cleaner column flotation, and attendant upgrades to the existing concentrate pumping and dewatering facilities. This paper will describe the SAG Plant flowsheet, and focus on the key training issues which contributed to a successful plant start-up.IntroductionP.T. Freeport Indonesia's operations in the Ertsberg mining district are located in the Jayawijaya Mountains of Irian Jaya, the easternmost province of the Republic of Indonesia. P.T. Freeport Indonesia (PTFI), the operator, is owned by Freeport MacMoRan Copper and Gold (81.3%), the Government of Indonesia (9.4%), and private Indonesian investors (9.4%). Geographical location, and sailing distances are provided on the attached location map.The operation stretches over 7 4 miles ( 114 km) from the dewatering and concentrate shipping facility at the Port of Amamapare on the Arafura Sea to the Grasberg open pit located at 3400m. The regional geology is covered in detail by Van Nort et al (1991 ), with current proven and probable reserves estimated at 1.13 billion metric tonnes grading 1.30% Copper, 1.42 ppm Gold, and 4.06 ppm Silver. The Grasberg open pit mining operation provides 92% of the mill feed, and is described in detail by Hickson (1991). The remainder of the mill feed is derived from several underground block caving operations. Current production rates provide a mine life in excess of 25 years. However, very favorable geology in the area leads to expectations that additional reserves will extend the life of the operation considerably."

Jan 1, 1996

By W. G. Scott

IT IS APPROPRIATE that your Institute should have chosen, for its 1956 Annual General Meeting, the Capital City of a province which is making such rapid advances in mining. The railway industry is proud to be playing an active role in this development, expenditures on equipment and railway construction in the Province of Quebec alone in recent years being in ?excess of a quarter of a billion dollars. In looking up some background material for this address I ran across a definition of a mine by Mark Twain, the great American humorist, which I thought might amuse you. He said that a mine was "a hole in the ground owned by a liar". I am sure that if he were alive to witness the enormous value attached to Canada's mineral resources today he would quickly change his definition. Canada's postwar record of mining development has been staggering in its variety and enormity. Historically, only the ?construction of our transcontinental rail ways outranks the largest of three of these development projects - the aluminum undertaking at Kitimat; the Quebec-Labrador iron ore deposits ; and the petroleum and natural gas developments in Wes tern Canada.

Jan 1, 1956

"AbstractThe Sedimentary Basin area of Western Canada, which lies between the Precambrian Shield and the Cordilleran mountain area, covers approximately 800,000 square miles. Sediments ranging in age from Cambrian to Tertiary are present and, of these, horizons in the Upper and Lower Cretaceous, Jurassic, Mississippian, and Devonian have yielded commercial oil and gas flows. Producing horizons in the Cretaceous and Jurassic are sandstone, while all those of the Palaeozoic are carbonate rocks such as red limestone or dolomite (bioherms). Shows of oil and gas have been encountered also in the Cambrian and Triassic sediments.The broad structural features of this vast expanse of sedimentary rocks are the Moose Jaw syncline, the Sweet Grass-Battle River arch, the Alberta syncline, the Foothills belt, the Rocky and Mackenzie mountains, the Great Bear-Slave Lake basin, and the Mackenzie Delta Basin area.This contribution outlines the .stratigraphy and structure of the Basin area, and gives examples of present producing oilfield structures and stratigraphic traps.Part 1.-Regional StratigraphyIntroductionThe vast expanse of relatively undisturbed sedimentary rocks of western Canada has long been recognized as prospective territory to search for oil and/ or gas. This search in western Canada dates back before the turn of the century, but, considering the size of area to be explored and tested, the effort an<l money expended upon it, which, before the recent discovery of oil at Leduc, Alberta, appeared large and fruitless, now seems almost ridiculously small. A check-up of effort and money expended prior to and since the Leduc discovery would undoubtedly reveal that more wildcatting and development has taken place during the last two and a half years than during all previous years combined. The figures would astound not only the average citizen, but many within the industry itself."

Jan 1, 1950

By E. Henderson, L. K. Daneshmend

Drawpoint control is critical in determining the cutoff point for load-haul-dump mucking operations to minimize dilution. It is also necessary to ensure even mucking distribution and to prevent possible hang-up of material within a stope. A prototype production monitoring and reporting system has been developed for load-haul-dump operations in under-ground mines. The system generates accurate and timely information regarding mucked tonnages and drawpoint and ore/waste pass utilization. The monitoring system integrates a PLC-based load weighing system with a radio frequency identification (RFID) system for locating the vehicle. The system records the identification and time of entry and exit of each draw-point and ore/waste pass visited during a shift, as well as the weight of each bucket load. A trial of the system was conducted at the CAN-MET Experimental Mine near Val d’Or, Quebec. The monitoring and reporting system functioned as designed, with the exception that the maximum read range of the RFID tags under dynamic conditions was found to be a limitation. RFID systems with greater range capabilities have been identified for a second generation system. The system is the first of its type in North America to demonstrate that RFID tagscan be successfully applied to locate trackless underground equipment. Because of their ability to locate equipment and personnel within underground mines, RFID systems should be considered a key technology for future mine information and process control systems.

Jan 1, 1996

By Allan A. Este, Bruce Arthur

"Rio Algom&apos;s Stanleigh Mine and Mill Operation Was&apos; officially started up in August 1983. In September 1982, Rio Algom contracted Estonix International Inc. from Lively, Ontario, to develop and implement two innovative programs: (1) Work Renovation Planning, and (2) Systems Performance Training. This paper deals with the development and implementation of these two concepts relative to the plants technology from start-up to present and the exceptional results achieved. This paper discusses how a small but motivated workforce resulted in the smooth transition from startup to full production. It also deals with how these concepts were applied elsewhere in the organization which permitted a successful transition and downsizing of the over-all operation.IntroductionRio Algom Limited produces uranium in Elliot Lake, Ontario. In the late 1970s Rio Algom entered a contract with Ontario Hydro to supply uranium from its Stanleigh property, which had been idle since 1960. The mine was subsequently upgraded, and a new modem mill was designed and built, commencing operation in 1983.From then until September 1990,Rio Algom had three producing mines and mills in the Elliot Lake area. Quirke mill, with a capacity of 6350 tonnes per day, operated continuously from 1968. The Panel mill with a 3000 tonnes per day capacity, operated since 1979. Stanleigh mill continues to operate under long-term contracts, although at a production rate about 25070 lower than its rated capacity of 5000 tonnes per day.Both the Quirke and Panel mills, although not entirely similar, were conventional uranium mills utilizing crushing, grinding, leaching and ion exchange. As such, and in keeping with the traditional management style, there was a rather large mill operating workforce, which utilized a line-of-progression job classification system."

Jan 1, 1993

CONSTRUCTED WETLANDS (CWs) ?Human-Constructed ?Built Specifically to Remove Contaminants ?Can Treat a Wide Variety of Wastewaters Including Stormwater(SW) ?Three Major Kinds ?Pond Wetlands ?Free Water Surface Wetlands (FWS) ?Sub-Surface Flow Wetlands (SSF) ?HSSF & VSSF

May 1, 2009

By Lebeau M., P. Duguay

"The cost of occupational injuries and diseases in the mining industry in Quebec was estimated for the period of 2010 to 2012. The method used takes into account the financial and human costs assumed by employers, workers, and the community. To better direct research and prevention toward issues with the most significant consequences, the results are presented in various ranking tables, which stakeholders might find useful.RÉSUMÉ Le coût des accidents du travail et des maladies professionnelles dans l’industrie minière au Québec a été estimé pour la période 2010-2012. La méthode utilisée prend en compte les coûts financiers et humains endossés par les employeurs, les travailleurs et la communauté. Afin de mieux orienter les recherches et la prévention vers les problèmes ayant les plus graves conséquences, les résultats sont présentés dans divers tableaux de classement, qui seront d’une grande utilité aux parties prenantes. INTRODUCTIONThe mining industry is much safer today than it was 30 or 40 years ago, mainly due to a more qualified workforce, the use of automated equipment, and a corporate culture more focused on occupational health and safety (OHS); however, the number and the severity of occupational injuries and diseases continue to make this industry one of the most hazardous. In the province of Quebec, the mining industry accounts for approximately 0.4% of paid workers but is the source of 4% of fatal work accidents. It is, therefore, important to continue the prevention efforts already underway in the mining industry.The difficult global economy, which has affected the mining industry in the last few years, is an opportunity to reaffirm that sound management of OHS can have a positive impact on companies’ productivity and profitability. Occupational injuries and diseases are costly for the companies concerned and for society as a whole. Reducing their occurrence makes it possible to reduce not only the size of workers’ compensation board contributions but also several other financial and human costs."

Jan 1, 2018

By K. Sakai, M. Miyaue, T. Aoki, T. Tani, S. Tanaka, N. Kudo

In the planning stage of a tunnel, due to limited available technology in the geological survey and the financial restriction, tunnel supports are often designed from unsatisfactory information, and the tunnel construction is started. Therefore, "observational construction" is carried out in the construction stage, in which the design is rationally verified and modified by observations/measurements. Moreover, the ground conditions ahead of a tunnel face must be predicted for efficient and safe tunnel construction. The authors have examined effective prediction methods to the ground conditions ahead of a tunnel face under construction of a mountain tunnel (Aoki et al., 2010) in view of the established method (Schubert et al., 1995). Though the prediction method of Schubert et al. requires the displacement in the direction of tunnel axis, it is difficult to obtain its accurate data by the electro-optical distance meter. Then, we have proposed a method that uses tilt sensors installed at the tunnel crown near the face to obtain the slight tilting information. To measure inclination of the tunnel crown, this inclinometer was originally developed as a daily management measurement, such that the geological condition and its possible change behind the face could be detected early, and a steady advance and construction safety could be ensured. This paper describes the method of forward prediction mechanism and advantages of this proposed method. It then presents the typical results of a field demonstration test at a tunnel under construction. Lastly, the predictable range from the stratum boundary at which ground stiffness changes are discussed based on the results of three-dimensional numerical analysis.

Jan 1, 2015

By P. L. Schwartz

The present method of shipping potash to the myriad of consumers is inefficient, not only because of the extreme and unpredictable nature of seasonal demand, but also because railway car turnaround times are very lengthy. The Floating Train system employs unit trains of potash operating from Saskatchewan mines to distribution warehouses located throughout the six corn-belt states of Minnesota, Iowa, Wisconsin , Illinois, Indiana and Ohio, transshipment points at Thunder Bay and the U.S. waterway network, and, where applicable , large consumers. These unit trains would "float", meaning that they would not originate at the same mine nor terminate at the same warehouse on each trip . They would " float " freely among the origins, destinations and participating railways. The potash would be shipped uniformly throughout the year and usually stored in warehouses located within the six states. It would be subsequently delivered to consumers within a 75-mile radius. Distribution warehouses and rolling stock would be provided by a new company, Potash Distribution Limited, consisting of major potash producers and the Canadian railways. Potash Distribution Limited would be responsible for the distribution of potash from the origin through the warehouses to the final consumer. The additional costs of providing warehouse space and outbound delivery will be offset by the reduction in both rail rates and "peaking" expenses.

Jan 1, 1978