Search Documents

By Lynn Crayne

We used Glyoxal as the hardener, at a final concentration of 10% by volume and therefore 20% by volume in the A-Component. They worked pretty well what we did was we shaved the joints on each of the pipes when we assembled them so they wouldn't rip the packers and then we greased the packers very well going in. We had to replace some but we have any getting stuck or didn't lose any pipes.

Feb 10, 2003

By Raymond Henn

Yes we have also used some however, again because of the nature of the maintenance window where we have that two hour (at best) window every night and due to the numerous other crews that are wanting to get in to do the other types of maintenance activities, we don't know if we are going to be getting into that same area from one night to the next. So even with the dormancy additives that one can add to cementitious grouts (that are good up to 72 hours) we don't know if we are going to get back in to the same locations from one week to the next. That's why I use the term "the forgiving nature of the acrylamide". It allows us to ream out the hole allowing us to use the exact same hole without having to re-drill a new hole. The program started in 1997 and we have a budget between labor/materials and equipment of 4.5 million dollars on a year to year basis. For the next few years that is going to come down drastically because the program is going to be more of an ongoing maintenance program. The program started in 1997 and we have a budget between labor/materials and equipment of 4.5 million dollars on a year to year basis. For the next few years that is going to come down drastically because the program is going to be more of an ongoing maintenance program. Up to the end of 2001 we were just over 1.7 million liters of between AV100 and AV118 grout. Of that, approximately just under 200,000 was AV100 and the remaining balance was AV118.

Feb 10, 2003

By Lois G. Schwarz

I did not make studies about this parameter but I can say that some researchers recommend using low C3A cements to repair masonry mortar in order to reduce a possible combination with sulphate that can be present in old mortars.

Feb 10, 2003

By Lois G. Schwarz

I did a project (Sungai Piah) as a consultant to your firm in Malaysia, where we were faced with a similar situation as sketched out in your question. The following is what we did for the grouting of the primary holes, which were both located upstream of the plug as well as downstream: We used a hydrophobic MDI based semi-rigid polyurethane prepolymer in the first phase of the grouting operation when grouting under water flow conditions. Then in the second phase and also for the contact grouting we used a two component water compatible polyurethane elastomer. And then for deeper formation grouting, when all the water flow had been stemmed in the vicinity of the plug, we used a regular (balanced stable) cement based grout. So it may not exactly answer your question, but we first used hydrophobic grout because it is very efficient to grout a formation through which water flows. We didn't stop all the leaks day-lighting downstream of the plug or all water running through the formation near the plug, but the flow of water through the rock formation adjacent to the plug was reduced by 99.9%, after completing the urethane grouting. This facilitated the placement of cement based suspension grouts without wash-out.

Feb 10, 2003

Paper 1: Risk of gastrointestinal cancers from inhalation and ingestion of asbestos, John F. Gamble Selikoff suggested the hypothesis that asbestos exposure is causally associated with increased risk of gastrointestinal (GI) cancers in an early study of insulation workers. In this paper, John Gamble reports on his extensive review and reanalysis studies that address the relationship between asbestos exposure and GI cancers. The purpose of the review was to evaluate the association between asbestos exposure and risks of stomach, colorectal, colon, and rectal cancers separately. Gamble evaluated exposure?response (E?R) relationships using surrogate exposure methods ??because few individual studies of GI cancer have reported exposure? response analyses.?? The principal asbestos exposure surrogates are: (1) the rate ratio (RR) for lung cancer; and (2) the percent of mesothelioma among exposed workers. Analyzing SMRs for GI cancers from individual studies versus the risk of lung cancer and mesothelioma provides crude estimates of E?Rs for asbestos exposure and GI cancer. Briefly, Gamble justifies the surrogate approach as follows:

Jan 1, 2007

By James Warner

Investigations of the sinkhole indicated that the loose, disturbed ground was completely encircled by dense competent core. This confinement substantially increased the effectiveness of the compaction grouting compared to what might have been expected at a "greenfield" site. However, the 8 ft diameter circle shown in the plan view was only the surface expression of the sinkhole proper and the deep, loosened ground actually extended to a larger diameter of about 20 ft. The planned spacing of the grout holes was based on the finite element simulations using a target void ratio of less than 0.3 throughout the compacted ground within a 5 ft radius of the grout injection point. Because of the strong confinement effect, the layout of grout holes included one central primary hole surrounded by six secondary holes at a triangular spacing of about 5 ft. Since the disturbed ground was considered a confined cylinder, it was anticipated that the primary hole would perform the majority of work and the secondary holes would act as check holes, with progressively lesser grout takes as the loose ground densified.

Feb 10, 2003

By Masaki Kitazume

Five papers were presented orally to the topics of Jet Grouting and Deep Mixing. The session was started with a brief introduction by the moderators. Following the oral presentation, floor discussions were directed by the moderators. A brief introduction of each of the oral presentations is provided before each discussion.

Feb 10, 2003

By George J. Tamaro

The design and construction of foundations in the New York City area are usually dictated by the widely varying geologic conditions encountered in the five boroughs, particularly along the spine of Manhattan Island. Rock extends well above sea level at the northern reaches and falls to depths in excess of 250 m at the barrier islands at the southern extremities. These highly variable geologic conditions, significantly affected by glacial activity, dictate different design and construction approaches throughout the five boroughs of New York City. Extensive rock removal is required at the north while long piling is dictated in the south. Similar changes can occur within a project site on Manhattan Island. This paper will describe these conditions in general, will identify the various solutions used to solve these problems and will summarize various foundation types used in the New York City area.

Jan 1, 2000

By Arturo Ressi di Cervia

From the times when men in lacustrine environments drove wooden piles into the mud to elevate their dwellings, until the beginning of the twentieth century builders reacted to the conditions found in the location of their proposed structures by attempting to distribute their loads in ways that could be supported by the foundation's soils; or, if those were unsuitable, by moving the structure, whenever possible. While many major structures were built on stable ground (the pyramids were founded on rock), others were built on [ ]

Jan 1, 2000

By Martin J. Kenwright

Within the famous Harrods department store, a new lift shaft has been constructed, servicing a depth of 22m below ground level as well as the existing 6 storeys of the store. The shaft will connect with a new goods tunnel which is to be excavated beneath the shop, as well as new floor space above ground level which has resulted from the infilling of a previously existing lightwell within the store. The construction of the deep shaft while maintaining uninterrupted use of the store by the Client led to a number of innovative solutions being undertaken. Empirical assessments were made of settlements anticipated from the construction process, which took place within a congested environment of existing foundations. Various elements were designed and installed to mitigate the effects of the inevitable ground movement on the surrounding overlying structure, which supported sensitive high quality finishes and mechanical and electrical installations The reinforced concrete lining of the shaft was contained within a cofferdam of minipiles. The minipile placement accuracy (1 in 150) was vital as it could not interfere with the subsequent tunnelling works. As the scheme progressed this became even more critical since the minipiles were needed as support for parts of the permanent works This paper describes:- the high quality placement and control of the minipiled cofferdam, the methods employed in assessing ground movements and the techniques used to mitigate against the effects of these movements.

Jan 1, 2000

By Wolfgang G. Brunner

The closing of the gap in the European waterway- net is one of the big and challenging traffic projects following the German reunification. The water canals in the North German plain connect the Rhine river, the border between Germany and France, with the Oder, the German border river to Poland. As early as in the 30's of the 19th century the planning and construction of a ship- lift and a canal bridge started, in order to close this last big gap in the system between the Mittelland Canal and the Elbe- Havel Canal near Magdeburg. This main waterway connects the West of Germany, known for its coal mines and steel mills, with the capital Berlin, and from there it goes on into Poland. The building activities started in 1934 but came to a complete stop in 1942 because of the war. The communist government in East Germany was not interested in continuing this huge project, including the ship lock Rothensee, the canal bridge crossing the river Elbe, the former border river between West and East Germany, and the lock Hohenwarthe due to lack of political backing along with low construction capacity. Now this important project is in progress and this report describes the special foundation techniques used on the great ship lock Hohenwarthe. Hohenwarthe is a double- bay ship lock of considerable scale, which is notable for recirculating water rather than letting it flow. It includes 44 800 m2 ( 481 720 sq. ft) of up to 55 m ( 180 ft) deep cut- off walls, ground water control, 1248 bored piles with a depth of 22 m ( 72 ft ) serving as foundation and 28 000 m ( 91 864 ft) of soil densification with vibroflotation equipment for ground improvement. In the year 2003 the project shall be completed and all ships can travel from the West to the East through Germany without expensive and time- consuming detours through other canals and locks.

Jan 1, 2000

By Sharwood M

Welcome to the morning of the second day of Minval '89. There are some three hundred and fifty of us here today. That represents certainly the most influential gathering of the mining and investment community in Sydney for a very long time, and on behalf of the Institute I bid you all a very great welcome. Due to the pilots' strike some of you have arrived by very unusual methods and others have travelled long distances. So for those of you that have made a special effort, thank you very much. Inevitably some people have not been able to get to Sydney and this has led to some minor programme changes. I'd like to thank our sponsors. Our underwriting sponsors are Energy Resources of Australia, Neil Cole & Associates, Resource Finance Corporation and Robertson Australia Limited, and to those firms thank you very much. To our major sponsors, County NatWest, I would like to say a particular thank you. County is the lead sponsor for Minval '89. They've :made an important contribution to the programme, and we're indebted to them for this support. We look forward to County's continuing involvement in the programme today. County NatWest is a major participant in the Australian equities markets and a growing merchant banking organisation in this country. It's parent organisation, National Westminster Bank, isa leading UK domiciled bank which is also active in Australia. This session is the Pancontinental Mining Ltd sponsored session, and I'd like to record the gratitude of the Australasian Institute of Mining and Metallurgy to Pancontinental for its generosity in sponsoring the session. This morning's session focuses on valuation and follows on from yesterday's proceedings which looked particularly at the impact of NCSC draft Policy Release Number 149. Robert de Crespigny, who was to have been the Chairman of this morning's session, has had some special problems with the pilots' strike.So we have the privilage to have in his stead Michael Sharwood.

Jan 1, 1989

By Philip Peck

Mine closure issues ?Narrow issues: ?Environmental focus; ?Broad issues: ?Social issues and sustainability; ?Continued importance of mining; ?Historical legacies from closed mines; ?Barriers to development; ?Migration [ir]reversibility Dealing with closure issues ?A matter of choice ?Option 1: Engagein solving closure problems as best possible; ?Option 2: Exit, leaving the playing field to firms not interested in solving problems ?Option 3: Delay, till better time to enter or until early entry [by others] fails and pick property up cheap [?].

May 1, 2006

By C. Jewell, G. H. Rupay

"67 - 2:15-3:00Regeneration of Hydrochloric Acid from Waste Pickle Liquor Using a Fluidized Bed Reactor System. G. H. RUPAY and C. JEWELL, Dominion Foundries and Steel Ltd., Hamilton, Ont.The disposal of acidic waste liquors from pickling processes has always been a problem for the steel industry. With increased awareness toward environmental control and the problems acidic wastes create, processes utilizing recovery and regeneration of the waste acids are becoming more popular. This paper describes the Keramchemie/Lurgi process for regenerating hydrochloric acid from waste pickle liquor using a fluidized bed reactor system. The process parameters are outlined, together with a brief description of the equipment. This is followed by a discussion of the operating problems and concludes with economic data."

Jan 1, 2000

G. B. Southward, Mechanization Engineer of the American Mining Congress, Washington, D. C., presiding. PRESIDENT HERRES: If you will come to order, please, we will get started on this morning's program. This morning's program takes up the matter of mechanized mining, particularly mechanical loading. There has been considerable progress made in the West with mechanical loading, but we are interested particularly in what is being done in other fields. We are particularly fortunate in being able to have with us Mr. G. B. Southward, Mechanization Engineer of the American Mining Congress. Mr. Southward has devoted his time for the past several years entirely to a national study of mechanized mining. He is the author of the Year Book published by the American Mining Congress, which is the authority for progress and development on mechanical loading. Mr. Southward has come here from Washington, D. C., particularly for this meeting. We have asked him to speak on the national phases of mechanized mining, and particularly on what is being clone in the East, since we are familiar with what is being done in the western field. I take great pleasure in introducing Mr. Southward. (Applause.) MR. SOUTHWARD: Mr. President and Gentlemen: Before starting on this gaper, I would like to express to all of you and to your President my appreciation in being asked to come here. It is a privilege. This question of coal mine mechanization, as you all know, is a big one. It is too big a problem for any one company to handle and it is through such meetings as these, through the co-operation of the various companies throughout the United States, that we have been able to make the progress that we have made. As Mr. Herres has said, I am not going to try to tell you gentlemen anything that is going on out here, in the West. You already know that yourselves. But he has asked me to give a brief resume of the progress that mechanization has made in the eastern coal states.

Jan 1, 1929

PRESIDENT HERRES: Our ses¬sions this afternoon will be on safety. They will be under the direction of Mr. Dan Harrington, who has come here from Washington, D. C., particularly to preside at these meetings. I do not think Mr. Harrington needs any introduction to anyone present. He is a member of both the A. I. M. E., and the Rocky Mountain Coal Mining Institute, and has been for a great many years. The Rocky Mountain District is his old stamping ground. I take pleasure in turning the meeting over to Mr. Harrington. (Ap¬plause.) DAN HARRINGTON (Chief Engineer, Safety Division, U. S. Bureau of Mines, Washington, D. C.): Gentlemen, I suppose you have rather a long program, so there is no necessity for any introductory remarks. Inasmuch as I have rather a long-winded paper of my own, I presume the best thing I can do is to go ahead and read it. Mr. Herres asked me some time ago if I would preside here, and also have a paper, or at least have something to say to the Institute on safety. I thought it best to put whatever I had to say in written form, so I would know exactly what I had said and so I would be able to, if necessary, defend it later on.

Jan 1, 1929

By V. N. Sukhov

This set was developed to use the mathematical methods and computers in the data analysis and accumulation of the large amount of geological data to solve the typical geological problems at the deposit exploring stage as well as for planning and managing in the open cast deposit mining. That is to say, the set of tasks ensures the geological data base at the stage of the deposit exploring and also its further use and. updating at the exploration stage. The following main elements may be ear-marked in the complex: (1) geological data base (GDB), (2) the data input system, (3) GDB maintainance, (4) "Geologist" geological application package (GAP). Let us consider now each element purpose. 1) GDB logical structure is determined through five hierarchical substructures with a common root segment.

Jan 1, 1986

By Helen S. W. Chow

The use of piled raft foundations for tall buildings has been increasing in this decade as it is an economical alternative to conventional piled foundations. Piled rafts are composite structures comprised of the piles, raft and soil and so soil-structure interaction is important in computing the behaviour of the foundation. In this paper, the behaviour of piled rafts subjected to non-uniform loadings will be examined where the raft is supported by piles of different lengths. Finite layer techniques are used for the analysis of the horizontally layered soils and finite element techniques are used for the analysis of the raft and piles. This method accounts for the soil-structure interaction and the lateral resistance of the soil on the piles and raft. Results provided from the present method are compared with the results of a full 3D finite element analysis.

Jan 1, 2006

By V. A. Preto

The Rexspar uranium deposit is located approximately 5 kilometres south of Birch Island, B.C. Three separate zones of commercial-grade uranium mineralization mineable by open pit have been outlined. Uranium and fluorite-celestite mineralization occur in a trachytic member of alkali-feldspar porphyry, lithic tuff, tuff breccias and pyritic schist conformably interlayered with a succession of strongly deformed greenschists and fragmental rocks that are, in large part at least, of volcanic origin. The age of these strata is not precisely known, but they are considered as part of the possibly Mississippian Eagle Bay Formation. Commercial-grade uranium mineralization is always associated with fluorphlogopite-pyrite replacement of the trachytic unit and is contiguous to, but separate from , a zone of ore-grade fluorite mineralization. In all zones, ore occurs in lenses of variable thickness and lateral extent, which lie parallel to the schistosity of the trachytic rocks and surrounding greenschists. The principal radioactive minerals at Rexspar have been identified by other workers as uraninite, uranothorite, bastnaesite, torbernite and metatorbernite. Considerable amounts of thorium oxide and widespread rare earths have been reported from all three radioactive zones. The geology of the deposit suggests that the trachytic rocks represent a highly differentiated intrusive-extrusive system in which fluorphlogopite, pyrite, fluorite and uranium-bearing minerals were deposited late in the evolution of the system by deuteric, volatile-rich fluids. The considerable amounts of thorium and widespread rare earths associated with the uranium tend to support the thesis that this element is of primary origin rather than secondary.

Jan 1, 1978

By C Mpodozis

Central Andean (22¦S to 34¦S latitude) Miocene giant ore deposits share common features that reveal their origin. Tectonic and magmatic features include a relation to a shallow subduction zone, an association with the waning or initiation of a magmatic episode, emplacement at the time of uplift associated with crustal thickening and formation at times of major magmatic changes along the Andean margin. Rare Earth Element (REE) signatures in magmas erupted near the time of mineralisation indicate a progressive change from equilibration at depth with a hydrous, intermediate-pressure amphibole-bearing mineral residue to equilibration with an anhydrous high-pressure garnet-bearing assemblage. These features point to a common history. First, a relatively shallow subduction zone leads to hydration of a cool mantle wedge providing a source of fluids which builds up over at least several million years. Arc magmas formed at this time equilibrate with a hornblende-bearing residual mineralogy. Second, a compressive tectonic regime leads to crustal shortening and thickening that facilitates entrapment of arc magmas in the crust. Eventually, the magma-weakened crust yields to horizontal compression causing rapid crustal thickening. Fluids required for mineralisation are liberated as amphibole-bearing assemblages break down to garnet-bearing ones and over pressured fluids are released from plutons. Mineralisation subsequently ceases in the region unless continued dehydration of the slab and mechanical thinning of the continental lithosphere causes the previous conditions to repeat. The type of mineral deposit generated depends on the pre-existing continental lithosphere and the distance from the trench.

Jan 1, 1999