Search Documents

By M. Carrales

This Bureau of Mines report presents information on the sulfur content of crude oil in the United States and in some foreign countries. Data are presented for oil produced in 1971 from fields in 26 States that accounted for about 76 percent of total U.S. oil production; the foreign data cover fields in 24 foreign countries that accounted for about 64 percent of the total oil produced from these countries in 1971. Most of the data are presented in tabular form.

Jan 1, 1975

By P Rubie, B Morgan, J Russell, C Stewart

The relationship between efficient liner exchange, concentrator availability and concentrator profitability is well documented. Russell Mineral Equipment’s (RME) relationship with OZ Minerals’ Prominent Hill site personnel enabled sound collaboration between the two parties. Both parties worked together to identify the sources of productivity and efficiency loss and developed solutions to reverse them.This paper chronicles the identification of production inefficiencies and the resulting removal of mill relining from the critical path through the materialisation of mill relining optimisation strategies. Furthermore, this paper outlines other recent mill relining optimisation strategies developed by RME and tested at Prominent Hill, to demonstrate and achieve further productivity, efficiency and safety improvements.CITATION:Rubie, P, Russell, J, Morgan, B and Stewart, C, 2017. Mill relining optimisation – a story of collaboration, in Proceedings MetPlant 2017, pp 335–345 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

Results of flotation tests on lead-zinc ore from Broken Hill, N.S.W., confirmed that flotation at pH 9 in the presence of cement gave poorer metallurgical results than flotation at pH 7. Additions of 2 kg/tonne wood raspings [e.g. blackbutt (Eucalyptus pilularis), blue gum (E. saligna), brushbox (Tristania conferta), or turpentine gum (Syncarpia laurifolia)l had little effect at pH 7 but greatly accentuated the deleterious effect of cement at pH 9. This was shown to be caused by e:xtractives (e.g. polyphenols and carbohydrate materials) derived from woods at pH 9. The proportion of extractives, as shown by DV absorbance spectra, increased with increase of pH and was affected by various salts.Additions of 1 kg/tonne Al2(S04)3.16H20 when cement or cement and wood were present showed that metallurgical results obtained by flotation were then very simHar to those in the absence of cement or wood or both. This was ascribed to lower pH values in the presence of aluminium sulphate and possibly to specific chemical effects.Additions of aluminium sulphate appear to offer an economic solution to the problem of treatment of ores contaminated with cemented fill at Broken Hill.

Jan 1, 1974

The object of this talk is to bring before members the importance of the prospector and the' State Battery system to the wealth and prosperity of the mining industry in particular and the State of Western Australia in general, and to touch on the more important features.Customs plants of any sort are usually subject to a good deal of critioism, usually on the large profits made at the expense of the customer, etc., and this often clouds the real value of the work being done.Prospectors, on the whole, are a good class of men; they work under conditions and difficulties which would deter those less spirited. Food, water and mining supplies are often difficult to obtain and frequently have to be transported great distances. Their mining tools are usually of the most primitive type, yet during last year over 109,000 tons of prospectors' ore were handled by the State Battery system for 73,250 fine oz. valued in Australian currency at over £587,000, the value being 57/- per long ton at par.This production brings the State Battery system into fourth position amongst the producers of the State, the yield being exceeded by the Lake View and Star, Wiluna and the Great Boulder.In passing I might mention that these notes were written at the end of the year 1940, and the above figures were for the previous period. The figures for last year, 1940, were not quite so good, being 101,000 tons for approximately 60,000 fine oz., valued in Australian currency at £572,000.In spite of this drop the State Battery system maintained its position as fourth in order of gold output for the State.The extractions, as a whole, throughout the system, were 92·54%, made up of 68·86% by amalgamation and 23·68% by cyanidation. These figures, for a group of 20 plants treating widely different classes of ore, must be considered satisfactory. The total production since inception is over £11,000,000 in Australian currency.State Batteries are usually more or less of a standard design. Ore is reduced to about 2i in. maximum size before being sent to the bins. Challenge automatic feeeders control the feed to each mill unit, amalgamated copper plates collect the free gold. Corduroy strakes are used with some ores after amalgamation, but in only a few cases has this been found of any advantage to the customer.The pulp from the battery is sampled, after leaving the tables, with a "Tazewell" sampler and pumped to dams for subsequent cyanide treatment.The "Tazewell" sampler is a machine driven by the moving pulp; and takes about fifteen dips per .minute from such pulp through a slotted...

Jan 1, 1941

By Robert Stefanko

With passage of the Clean Streams Act of the Commonwealth of Pennsylvania and its impact on the coal industry, considerable research has been conducted to explore various approaches to the problem, including deep-well disposal. Available drillhole data from gas and oil wells were used to develop cross -sectional maps for various portions of the state and potential disposal zones were evaluated. Bethlehem Mines Corp., faced with a severe water problem at its Marianna operation in Washington County, cooperated with the Dept. of Mining at The Pennsylvania State University in establishing a 1500-ft well into the Salt Sands for the purpose of determining the feasibility of mine water disposal. The thickness, porosity, and permeability of the formation at the well site proved to be below what had been anticipated from drillhole data. Further, subsequent hydraulic fracturing did not improve the flow characteristics of the well; pumping pressures remained in the range of 1800-2000 psig for disposing of water at the rate of 150 gpm. The legal problems of disposal at the site were very formidable. When the Salt Sands proved to be less than satisfactory, permission could not be obtained to dispose in other promising formations. The paper details many of the problems associated with the experimental well and makes an assessment of the potential for deep-well disposal of mine water. The concept of disposing of liquid industrial wastes by deep-well injection is not a new one. Brines associated with crude oil long have been disposed of in this manner, with the additional benefit of aiding secondary oil recovery. More recently, with the expansion of nuclear energy, the lethal, highly radioactive wastes which are by-products of the fission process have created severe disposal problems. During the past ten years, a variety of industries have resorted to subsurface disposal, some of the details of which are given e1sewhere.l,2 The list reveals wide variations in injection rate, pumping pressure, cost, and waste disposition. Included are successful installations in Western Pennsylvania. Enactment of more restrictive clean-water legislation in Pennsylvania recently had a great impact on the coal industry. Among its provisions was the reclassifica-tion of most mine water as industrial waste whose dis-posal is prohibited in any stream of the Commonwealth. This had the effect of accelerating research in a variety of areas, although treatment methods still retained primary interest. When a feasibility study of deep-well disposal was proposed to the Pennsylvania Dept. of Mines and Mineral Industries, the Coal Research Board (CRB) approved it. This paper summarizes the efforts on this project. Acid mine water is a chemically complex liquid. having no definite quantitative relationship among its constituents. However, it is the iron disulfide (FeS2) associated with practically all coal seams that produces the objectionable products present in acid mine water when combined with air and water. The principal contaminants are sulfuric acid (H2SO,) and ferric hydroxide (Fe(OH)2. Ferric hydroxide is a rust-colored gelatinous precipitate that coats stream bottoms and destroys aquatic life. However, other ions and bacteria are present in acid mine water in varying amounts.

Jan 1, 1971

By M. Drozd, M. Somppi, Z. Yamak

"Granular activated carbon is widely used in the gold mining industry for gold extraction from aurocyanide-containing slurry. The extraction process can employ carbon as part of the gold recovery operation for various circuit designs including carbon-in-pulp (CIP), carbon-in-column (CIC), and carbon-in-leach (CIL) circuits. However, various qualities of activated carbon exist and the durability of the material can change significantly from source to source. Handling this expensive reagent can pose challenges when fine carbon losses occur in the CIP, CIC, and CIL circuits. Additionally, any gold that is adsorbed to these carbon fines can also be lost by various mechanisms including carbon attrition and fracturing, inefficient coarse-fine separation, and poor carbon fines capture. With the above in mind, a series of tests were conducted to investigate standardizing simple laboratory methods for testing carbon quality. A standard procedure beyond or enhancing ASTM methods can serve as additional starting points for evaluating carbon specific to the gold industry. The investigation focused on size distribution, flatness, wet attrition resistance, surface area, gold kinetics, and gold loading. The final results provided information to generate an equation for ranking carbon samples to plant performance.IntroductionActivated carbon for use in gold extraction is amongst the most commonly found processes in modern gold-milling plants. Although gold losses are inevitable in the milling process, operators often focus on the importance of maximizing gold recovery. One focus area that is important in gold recovery is optimizing the use of activated carbon and examining potential changes to realize improved economics for carbon-in-pulp (CIP), carbon-in-column (CIC), and carbon-in-leach (CIL) processes."

Jan 1, 2017

By William A. Beck

This report describes the loading and transportation practices employed at the zinc-lead mines of The Eagle-Picher Co., Jo Daviess County, Ill., and Lafayette County, Wis. The report also gives a brief history of the Illinois-Wisconsin zinc-lead district and the operations of the company in the area. The diesel-powered, rubber-tired loading and haulage equipment is described and illustrated from the operational point of view only, and an analysis is made of the materials-handling system without going into health and safety Factors. The costs per ton of the various components of mechanical loading, underground haulage, underground crushing, and hoisting for fiscal year 1960 are tabulated.

Jan 1, 1964

The alkaline ethylenediamine tetra-acetic acid (EDTA) leach process for extracting tungsten from scheelite (CaW04) ores has been examined for the treatment of low grade (<0.5 per cent WO,) residue dumps. The process has been considerably simplified by applying solvent extraction directly to the leach liquor.Ammonium paratungstate is thereby produced in a one step process and this obviates the need to physically recover EDTA prior to recycling. This modified process should be an economical method of tungsten extraction.

Jan 1, 1983

By Denise Cristina Oliveira Nascimento

Environmental considerations in addition to technical, economical and societal benefits are increasingly promoting the substitution of natural fibers for glass fiber in polymer matrix composites. However, natural fibers are heterogeneous in their dimensions, specially the cross section, which plays an important role in their mechanical strength. It has been found that the equivalent diameter of fibers such as sisal, ramie, pineapple and curaua correlates to different levels of tensile resistance. Piassava is a promising stiff natural fiber for composite reinforcement. In this work, a statistical analysis of tensile strength of piassava fibers using the Weibull methodology was performed. An attempt to correlate the fiber strength, obtained in tensile tests, with the diameter, precisely measured by means of a profile projector, was carried out. The results revealed an inverse dependence between the piassava fiber diameter and corresponding tensile strength. Fracture tip observation by SEM suggested a possible mechanism that could justify this inverse correlation.

Jan 1, 2010

By E. Amini

"While methods exist to allow the simulation and optimization of existing flotation operations, there is a deficit in the ability to predict the performance of a new ore type pre-processing. A laboratory scale batch flotation testing methodology has been developed to assess the flotation potential of ores (known as the JK Floatability Index or JKFI). Previous work conducted by Alexander and Collins (2008) showed that the test could be used to predict full scale results in base metal ores. In this work, JKFI tests were applied to three different types of ore and one blend from a greenfields gold deposit to show the test applicability to flotation of precious metals. The results from the JKFI test on one ore type were then used to predict the response of all ore types (including the blend). To validate the predicted kinetic parameters, a comprehensive survey was performed on a pilot plant where each of ore types was processed in the circuit. An acceptable agreement was found between the experimental recoveries and predicted recoveries which indicate the potential of this method for use in predicting the flotation response of an ore.INTRODUCTIONOver 100 years, flotation has been considered an efficient method to concentrate different types of sulphide and oxide minerals and coal. Thus, numerous research studies have been undertaken to find an appropriate model to predict the behaviour of particles in flotation circuits (Barnwal et. al., 2006; Bascur and Herbst, 1983; Cecile and Villeneuve, 1991; Deng et. al., 1996; Zheng et. al., 2006). Most methods are based on the ore flotation response in an industrial plant which is expensive and time consuming to characterise. It is difficult to reliably predict flotation response for new types of ores in industrial scale plants.The floatability component modelling (FCM) approach, developed within the Australian Minerals Industry Research Association (AMIRA) P9 project, has been used to derive models of operating flotation plants for the purpose of simulation and optimisation (Alexander and Morrison, 1998; Alexander et. al., 2000; Varadi, 2006). This approach has been applied at a large number of operating sites treating a wide variety of ores. The approach requires metallurgical surveys to be undertaken in conjunction with batch flotation tests and cell characterisation. This allows ore and machine parameters to be derived, which are then used in the P9 Flotation Model. The development of a FCM generally requires a large commitment of resources and time. While there has been significant support of this approach in industry, the FCM approach is limited to ores already being processed (Runge, 2004; Wightman, 2006)."

Jan 1, 2009

By Raymond W. Hiteshue

Experiments were conducted al temperatures of 480° to 800° C. and hydrogen pressure of 6,000 p.s.i.g. to determine the effect of coal residence time on the conversion of a high-volatile bituminous C coal to liquid and gaseous products when using a semicontinuous apparatus designed fur rapid heating and cooling of reactants. The objective of the studies at high temperatures was to determine if appreciable quantities of coal could be converted to gaseous hydrocarbons and low-boiling liquid hydrocarbons. Experiments at lower temperatures were designed to indicate shifts in product distribution with respect to temperature and to learn more about the general mechanism of the reaction when using close control of coal residence time. One percent molybdenum, based on m.a.f. (moisture-and ash-free) coal, was used throughout this investigation. At 800° C., 6,000 p.s.i.g., and "zero" residence time) the yield of gaseous hydrocarbons was about 38 percent and the yield of oil about 4.5 percent, based on m.a.f. coal. With IS minutes residence time, under the same conditions, the yield of gaseous hydrocarbons was approximately 80 percent with no increase in yield of oil. Apparently at 800° C., and hydrogen pressure of 6,000 p.s.i.g. coal was rapidly carbonized to char with expulsion of volatiles. Char was then slowly hydrogenated to gaseous hydrocarbons without production of oil.

Jan 1, 1962

By Harold Price

ONE year ago, that is in January, 1923, there had not been constructed a single oil-storage tank of 55,000-bbl. or more capacity with a completely electric welded roof and bottom. Today, there are at least fifty 80,000-bbl. storage tanks completed, or nearing completion, on which both the roofs and the bottoms are electric welded. It is the purpose of this paper to describe, in a general way, the construction of these FIG. 1.-ELECTRIC-WELDED SEAMS AND RIVETS OF BOTTOM IN 55,000-BBL. TANK AT EL DORADO, KANS., SHOWING ALSO PATCH PLATE WELDED TO BOTTOM. welded roofs and bottoms, and to give their advantages over riveted construction. All of the following data and conclusions were obtained from observations made during the welding of tanks by the Welding Engineering Co. at Texas City, Tex., and Tonkawa and Burbank, Okla. As far as can be determined, the first electric welding on large tankage was completed in May, 1922. At that time the Empire Companies of Bartlesville, Okla., discovered a badly leaking bottom in a 55,000-bbl. tank at El Dorado, Kans. They had considered concreting this bottom, but because of the much smaller cost, decided to try electric welding; so a- contract was given the Welding Engineering Co. of Bartlesville, Okla. In this instance, no new sheets were added, the bottom being repaired by electric welding of all seams and rivets, Fig. 1. In some places where the original rivets were missing, the holes were filled by welding; patch plates were also added at certain badly worn spots. This tank has since been in service over a year and half, but no other

Jan 6, 1924

By Leonardo Flores

"Minera Escondida operates two open pits on a porphyry copper district, southeast of Antofagasta, Chile. During 2005, ore will be delivered exclusively from one pit to two concentrators, while from 2006 both pits will provide ore to these plants. Annual testing programmes on drillhole samples, have allowed for the construction of hardness block models since 2000. These models have delivered two main hardness descriptors, the Bond work index and the SAG power index. These parameters and plant operational specifications have been used as input information to forecast, the expected throughput and ball mill product size (P80) for each block of ore. Two forecasting techniques have been used, an in house model, strongly dependant of bond work index and MinnovEx´s CEET2, dependant of Bond work index and Sag power index and other parameters. Model performance has been evaluated from reconciliating on a monthly basis, the forecasted throughputs against a recalculated plant throughput which accounts for losses in tonnage not caused by ore hardness but instead by unscheduled plant operation problems. The model performance for 2003 was ± 2% yearly and ± 5% quarterly, well within the expected ± 3% and ± 10%. INTRODUCTIONThe Escondida porphyry copper district is located 140 km SE of Antofagasta, Chile at 3150 m.a.s.l, at 24°16’ South latitude and 69°04’ West longitude (figure 1)."

Jan 1, 2005

By Ross Nairn

"Tulawaka Mine is a joint venture between Pangea Minerals Limited 70% (a wholly-owned subsidiary of Barrick Gold Corporation) and Northern Mining 30%. Tulawaka Mine is located in North West of Tanzania in the Lake Victoria Goldfields. Tulawaka Mine is scheduled to process 360,000 tonnes per year at an average 11.5 g/t head grade over a 4 year mine life.The Tulawaka Process Plant uses single stage crushing, single stage SAG milling, gravity, intensive leach of gravity concentrates, CIL, Zadra desorption and cyanide detoxification to process the ore. Gold recovery exceeds (or is expected to) 95%.The Process Plant was designed and constructed under the supervision of Ausenco Engineering of Australia. Site works commenced in January 2004, Process Plant construction commenced in July 2004 and the first ore was presented to the Process Plant 26th February 2005. The first gold was poured on 15th March 2005. All construction contractors were demobilized from site 7th April 2005. Major achievements have been 3.4 million hrs LTI free during construction and operation to date, training of the Tanzanian workforce at Bulyanhulu Mine prior to commissioning, a succession plan to replace expatriate personnel with Tanzanian staff and significant over performance of the Process Plant against design.INTRODUCTIONTulawaka Mine is situated approximately 160 km south west of Mwanza in the western Lake Victoria Goldfields District of north western Tanzania. The property is held under a joint venture between Pangea Goldfields Inc (70%), a wholly owned subsidiary of Barrick Gold Corporation, and Explorations Minieres Du Nord Ltée (30%). A location map showing the position of the operation in Tanzania is shown in Figure 1.Mine site staff at Tulawaka comprises a combination of Tanzanian and Expatriate personnel. All Pangea personnel live on site and commute to their place of residence for their R&R on a 9 weeks on 4 weeks off roster."

Jan 1, 2006

The effect of rare earth element Y (0-2.0at.%) on the microstructure of TiAl alloys at the as cast and rapidly solidified conditions has been investigated. The results show that the addition of Y greatly refined the microstructure of TiAl alloys at both conditions. The refinement is more significantly with higher Y content. The refinement of Y in the cast alloys is attributed to that the strip-shaped Y-rich phase locating on the grain boundaries impedes the grain growth during solidification. In the rapidly solidified alloys, Y-rich phase dispersing uniformly as spherical particles in the matrix acts as heterogeneous nucleation sites which increases the nucleation rate of ??phase during the ????phase transformation, and produces a refined initial microstructure during solidification. Higher cooling rate restricts the grain growth during subsequent cooling.

Jan 1, 2010

By R. H. Batey

"The process control and cost of monitoring mining slurries is normally accomplished using a continuous mass flow system, conventionally embodying a volumetric magnetic flow meter and nuclear density meter. DuPont’s Maxville Mine at Starke, Florida, USA was chosen to examine costs associated with performance of a nuclear density meter. Since it is typical of many mid-sized establishments and has a long history in their use. The published accuracy under ideal conditions of a nuclear density meter is ± 1.0%, but in practice considerable ambiguity of cost in annual production implies ± 2% at best. Using such accuracy in a 400mm (16”) pipe carrying zircon slurry at 75,000 tons/day, the cost of ambiguity, together with initial and running costs, amount to nominally $962,000 per year.Such cost leaves much to be desired. This paper describes an unique continuous, direct mass per unit volume Density Meter used for mining slurries in pipe sizes up to 1000mm (40”), which significantly reduces the cost of ambiguity of measurement and running costs. At the same time the disadvantages of nuclear devices are obviated.In an effort to reduce costs, a 400mm non-nuclear Density Meter was installed at the DuPont Maxville mine. A typical on-site accuracy can be shown to be ± 0.285%, whereby the cost of ambiguity, initial and running costs in the example above shows an annual improvement of $78,660, a reduction of over $880,000 per year.Even higher cost savings may be demonstrated with mass flow systems having gas entrainment compensation. Unlike nuclear and other inferential density meters, the signal quality of this non-nuclear Density Meter is totally unaffected by entrained gas found in mining slurries. This non-nuclear density meter is then ideally used with a vortex velocity domain sonic flow meter, and provides for the first time compensation in wet density or dry % solids, as well as wet or dry mass flow of mining slurries with entrained gas, resulting in enormous reductions in cost ambiguity."

Jan 1, 2013

By T A. J Hopper, B J. Birt, K K. Trofimczyk

Nuclear magnetic resonance (NMR) has been utilised in the oil and gas industry for over 60 years. The technology was recently identified as having potential value in iron ore, where latent bound moisture may affect ore handling even after dewatering and extraction. The first step in introducing this technology to iron ore involved laboratory tests on drill core samples. These results established the parameters for a downhole borehole magnetic resonance (BMR) tool for iron-rich environments, which was subsequently developed. A major challenge involved shrinking what is a very large tool in the oil industry to a slimhole, lightweight, 1-man deployable mining tool.Of primary concern was the ability to measure the very fast transverse relaxation times (T2s) seen in the lab results on iron ore samples. Iron creates local field gradients that significantly decrease the T2 times. As a result, the BMR tool had to be able to measure T2s in the range of hundreds of microseconds, a level not required in clastic sedimentary formations. The choice of T2 cut-offs in iron ore is critical to successfully separating the free and bound fluids. The industry has typically focused on T2 cut-offs in clastics and carbonates, but not in systems with high iron content. Using core analysis results (poro-perm and NMR) we were able to verify the BMR response. The T2 cut-offs were determined from NMR core analysis and then applied to the logs so as to provide a continuous, calibrated permeability log.Field results that highlight the challenge involved in logging in iron-rich environments are presented, as well as some minimum requirements for a successful BMR log. Examples from boreholes in an active iron ore mine in the Pilbara iron ore province in Western Australia are presented, as well as explanations for how NMR data can be combined with bulk density logs to provide a continuous dry weight density log based on the original density-porosity equation from Alger et al (1963).CITATION:Hopper, T A J, Trofimczyk, K K and Birt, B J, 2017. Development of a slimhole downhole nuclear magnetic resonance tool for iron ore – some applications and limitations, in Proceedings Iron Ore 2017, pp 473–480 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Cem Colakoglu

In this study, nickel containing iron alloys were produced by carbothermal reduction of lateritic nickel ores obtained from Manisa - Caldag region of Turkiye in order to investigate the reaction mechanism of nickel and cobalt. In the experiments, the lateritic ore containing 1.58 wt.% Ni and 0.12 wt.% Co was calcined in a semi-pilot scale rotary furnace at 1100°C for 1 hour. Then, a mixture of calcined ore and metallurgical coke was reacted in sintered alumina crucibles using a graphite resistance tube furnace at different time (0- 60 min) and temperature (1500-1600°C).

Jan 1, 2009

By Ronald F. Balazik

This Bureau of Mines study identifies and examines the costs of Federal, State, and local environmental protection controls on domestic phosphate rock mining, The costs include the expenditures needed to comply with government regulations and the effects that these expenditures and regulations have on supply. The study analyzes costs of environmental impact assessments, air and water quality standards, reclamation laws, potential solid waste controls, and local government restrictions. In addition, an industry survey and the Bureau's Minerals Availability System (MAS) are used to evaluate land management policies that restrict access to phosphate resources, Conclusions drawn from these analyses confirm that (1) domestic phosphate mining has incurred substantial control costs and may be subject to significant new regulatory costs in the next several years, (2) certain environmental controls can discourage mining investment, (3) environmental policies governing land-use controls affect the disposition of sizable phosphate resources, and are key determinants in the development of those resources on the Federal do- main, and (4) environmental costs could diminish the competitiveness of domestic producers.

Jan 1, 1983

By Michael Arnold, Jonathan Delgado

In 2017, Bauer Foundation Corp. (BFC) was awarded the contract to install the deep foundations for the new 17-story Hotel Tower and the Low Rise Casino Expansion at the Seminole Hard Rock Hotel and Casino in Tampa, Florida. The site was underlain by extremely challenging Florida Limestone geology and surrounded by occupied existing buildings and infrastructure. To overcome the challenges of the difficult subsurface conditions, and to successfully complete the foundation installation without impact to the surrounding buildings and casino operation, Langan Engineering (EOR) and BFC were required to modify both the design and installation techniques during construction. The scope of work included 147 temporarily cased drilled shafts to depths up to 230 ft (70 m) below ground surface (BGS), 76 permanently cased micropiles up to 200 ft (61 m) BGS, and more than 300 augered-cast-in-place (ACIP) piles up to 125 ft (38 m) BGS. Voids and zones of high permeability in the limestone created many challenges for execution of the foundation scope including ACIP piles overbreaks of more than 400% above neatline volume, and construction induced ground subsidence/collapses adjacent to structures supported on shallow foundations. This paper will discuss site limitations, design and construction challenges, difficult geology, varied soil conditions, and lessons learned. PROJECT The project is located at Seminole Hard Rock Hotel and Casino Tampa, Florida, as shown in Fig. 1. Seminole Tribe, the owner, started the construction of a new 17-story Hotel Tower and the Low-Rise Casino Expansion at the beginning of 2017.

Jan 1, 2018