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By Alexander Nikolic

The paper presents the foundation design and construction of a landmark urban redevelopment scheme in central London, UK. The scheme comprises the new Tottenham Court Road Underground station, Crossrail interchange box and associated over-site commercial development. The paper focuses on the design, procurement and construction of large diameter bored piles, up to 68m in depth, which form the foundation support system for the over-site commercial development at Denmark Place. The congestion below ground required an intricate foundation design solution which has been a catalyst for developing innovative load transfer arrangements and has resulted in the advancement of pile construction technology in the UK. The foundation system was also designed to cater for the construction of two significant elements of proposed below ground infrastructure. Selected large diameter piles have been constructed within 1.1m of live underground railway tunnels. An innovative D-shaped pile was constructed in a zone subject to particular spatial constraints. The proposed Crossrail tunnels will be bored within 1m of selected over-site development piles. In addition, a 30m deep excavation forming a new escalator box will be constructed in direct contact with the over-site development piles. The stakeholder engagement process is described together with the foundation design development and buildability assessment. The benefits from early collaboration between the designers and specialist contractors are highlighted. From an analytical design perspective, the entire foundation construction sequence was modelled in detail in order to assess the soil structure interaction and any potential adverse effects on existing elements of underground infrastructure. The results from the three dimensional numerical modelling simulation are compared with field monitoring data.

Jan 1, 2011

By Michael N. Greeley

The movement to reclaim abandoned mine sites has gained momentum as federal, state, and private organizations have increased their commitment and resources to tackle mutual, and often controversial, problems of health and safety. Numerous interorganizational agreements have been implemented to promote cooperation in the characterization of mine site hazards, development of mutually acceptable plans of remediation, and sharing of actual cleanup requirements. Working through these partnerships, the federal land management agencies have begun to focus on abandoned mine reclamation in selected, priority watersheds and other drainage basins. Although there are major difficulties to overcome, significant progress continues to be made.

Jan 1, 1999

By Jimmie C. Rosenbruch

The Federal Bureau of Mines evaluated the prospects for using geothermal energy to generate electricity for mines in remote areas. Given the development of a geothermal resource for this purpose, the subsidiary uses of space heating and agriculture were then examined to see if other industries might be viable given a cheap source of heat energy. Sites investigated were located in three areas of Alaska: Kobuk in the northwest, Unalaska in the southwest, and Stikine River in the southeast. Each site was relatively close to mineral deposits whose prospects for development would be enhanced with cheap power.

Jan 1, 1975

By D. W. Gillmore

Numerous orphaned strip mines and old refuse piles scar the landscape, contributing to stream pollution and degradation of the natural environment. Field experiments to reclaim acidic surface-mined spoil and refuse banks with fly ash from bituminous coal-fired powerplants were conducted at several sites in West Virginia. Fly ash served as a neutralizing agent and soil amendment, permitting vegetation of waste lands and disposal of large quantities of ash. Reclamation of land by this method is estimated to cost about $300 per acre of leveled site, depending upon the topography of the land and quality and availability of the fly ash.

Jan 1, 1972

By L McCallum, G Dale, B Silverwood, T Roscoe, A Costin

The introduction of Progressive Closure and Rehabilitation Plans (PCRPs) in Queensland from 2019 places greater importance on planning and implementation of mine rehabilitation activities. The progress and outcomes of progressive rehabilitation activities is monitored and reported upon to demonstrate success in achieving progress towards the approved post-mining landform, and to inform corrective action where required. The requirements of PCRPs place additional emphasis on mine sites to quantify the risks of successfully achieving planned outcomes. This is particularly challenging given mined-land rehabilitation is a complex process involving decisions on multiple inter-acting management interventions, climatic conditions and spatially variable site characteristics.

Aug 2, 2023

By Ihab Allam PE, Meeok Kim. PE. Ph. D

The wet weather equalization basin (EB) planned for Pacifica, CA is a 45 feet deep rectangular shaped underground water tank containing over 2.1 million gallons of water, and located only 500 feet away from the Pacific Ocean. The location and size of the water tank, and the geotechnical characteristics of the selected site presented many engineering and construction challenges. The engineering had to consider a structural system which can fit into the limited area of the site and yet need to meet the storage volume requirement. In addition, the system construction should meet the city’s tight budget and schedule.

By Stan Tang, Yiming Sun, S. Amir Reza Beyabanaki, N. Sathi Sathialingam

The Kurve mixed-use development project including a 22-story tower at 2801 Sunset Place was constructed on a site consisting of a roughly rectangular-shaped lot at the intersection of Wilshire Boulevard and Hoover Street in Los Angeles. Two Metro Red Line tunnels, with depths of approximately 30 feet and 58 feet, respectively, cross below the building at distances of approximately 1 foot to over 63 feet from the site. This paper presents numerical modeling performed to evaluate the ground and tunnel behavior in response to building construction. Results of geotechnical instrumentation and monitoring undertaken during the building construction are also discussed.

Jun 13, 2023

By L. B. Phelps

This paper focuses on the use of an integrated mine planing software package entitled "REMINE" which was constructed to provide a project evaluation tool for analysis of remining projects. Coal remining constitutes the affecting of sites which have had a past history of mining and have a pre-existing pollutional discharge. Such sites require a Best Professional Judgement (BPJ) analysis. The program was written to provide such an analysis with flexibility in the mine plans which can be analyzed. The process required for a BPJ analysis will be detailed and mine plan simulation performed to demonstrate the analysis.

Jan 1, 1990

By G. G. Marino

Little comprehensive information has been reported on the behavior of room-and-pillar mines. The objective of this paper is to present case data on mine failures in the Illinois basin for use in practice. Presented are results of an ongoing study and details on the site characteristics of cases where sags have developed on the surface. Site data are reported to show the geologic, mining, and sag conditions that existed. Sags mainly develop from pillar, floor, or pillar-floor failure. The character of the sags depends upon the type of mine failure as well as the overburden response.

Jan 1, 1989

By Angelina Anani, Nathalie Risso, Gail Heath, Dean Riley, Nilufer Akbulut, James Werner, Víctor O. Tenorio

Implementing a Digital Twin at the San Xavier Mine Laboratory (Sahuarita, AZ), requires a network redesign with a robust architecture. The goal is to create an ecosystem in where all personnel and equipment can be monitored in real-time from the University of Arizona campus, visualizing the site in a digital terrain model. A wireless mesh will help to test robots with autonomous features. Expected outcomes include data retrieval and analytics, the evolution of communications and safety protocols, tele-operation, and an innovated approach for managing the site with new supervision challenges. A timeline with expected commissioning benchmarks is also included.

Feb 1, 2024

By L. B. Phelps

Current mining regulations require revegetation in reclaiming surface nines. Excessive soil compaction can be an impediment to successful revegetation in poor soil conditions common to Eastern coal nine sites. A field study was performed to determine the bulk densities of soils that had been spread by either bulldozers or scrapers at a strip nine site. Moisture-density relationships for the soils were determined from the field samples. These were compared with stockpile samples compacted by the Standard Proctor compaction test. The results of the study indicate that the degree of compaction could be lessened through proper soil handling procedures.

Jan 1, 1986

By William W. Aljoe

The hydrologic characteristics of two abandoned underground coal mine sites, near Latrobe, PA, and Uniontown, PA, were investigated by the U.S. Bureau of Mines for possible implementation of alkaline injection into the mine pools as a means of abating their acid discharges. The Latrobe site was chosen for a one-time application of alkaline injection to achieve a partial, short-term neutralization of a limited portion of the mine pool. A quantity of alkaline reagent (sodium hydroxide) sufficient for a one-time neutralization of the water in this portion of the pool was added. Although nearly all of the neutralizing reagent had moved away from the injection wells within 6 weeks, no evidence of neutralization was noted at the mine discharge during the study period. This lack of neutralization probably occurred because the injection wells did not intercept a primary flow path through the mine. Criteria for successful application of alkaline injection at this or other sites include (1) positive identification of the primary flow paths through the mine pool and (2) addition of quantities of alkaline reagent sufficient to neutralize the entire volume of the pool along the primary flow path.

Jan 1, 2010

By Nadia C. Miller

In situ metals research to characterize the hydrology of a fractured crystalline rock mass in under-ground mine stopes is discussed. The objective of this study was to find the potential direction, velocity, and concentrations of a lixiviant plume, should leaching solvents (lixiviants) escape from a test stope. The study was conducted by the U.S. Bureau of Mines at the Colorado School of Mines Experimental Mine in Idaho Springs, CO. Since this was a method evaluation site, the lixiviant was simulated using water and acceptable tracers. The site is located in moderately fractured Precambrian migmatite-biotite gneisses of the Idaho Springs Formation. The data required for the characterization were obtained from geologic maps and reports, core logs, and air and water permeability tests. The acquired data were analyzed and applied to a computer model that calculated' the characteristics of a lixiviant plume originating at the stope. A sensitivity analysis showed that dispersivity, ground water velocity, fracture porosity, and fracture spacing had notable effects on the concentration of the plume. Assuming a saturated rock mass, the lixiviant plume would disperse to undetectable levels in a very short time because of a high fracture density at the mine site.

Jan 1, 2010

By D. R. Willmer

An understanding of how health and safety management systems (HSMS) reduce worksite injuries, illnesses and fatalities may be gained in studying the behaviors of health and safety leaders. These leaders bear the accountability for identifying, understanding and managing the risks of a mining operation. More importantly, they have to transfer this knowledge of perception, recognition and response to risks in the mining environment to their workers. The leaders’ efforts to build and maintain a mining operation’s workforce that consistently executes safe work practices may be captured through more than just lagging indicators of health and safety performance. This exploratory study interviewed six leaders in occupations such as site-level safety supervisors, mine superintendents and/or general managers at surface and underground stone, sand and gravel and metal/nonmetal mine sites throughout the United States, with employee populations ranging from 40 to 175. In exploring leaders’ perspectives on how they systematically manage health and safety, examples such as approaches to task training, handling near-miss incidents, identifying future leaders and providing workers with feedback offer insights into how leaders translate their knowledge and management of site-level risks to others.

Jan 1, 2018

By D. R. Willmer

An understanding of how health and safety management systems (HSMS) reduce worksite injuries, illnesses and fatalities may be gained in studying the behaviors of health and safety leaders. These leaders bear the accountability for identifying, understanding and managing the risks of a mining operation. More importantly, they have to transfer this knowledge of perception, recognition and response to risks in the mining environment to their workers. The leaders’ efforts to build and maintain a mining operation’s workforce that consistently executes safe work practices may be captured through more than just lagging indicators of health and safety performance. This exploratory study interviewed six leaders in occupations such as site-level safety supervisors, mine superintendents and/or general managers at surface and underground stone, sand and gravel and metal/nonmetal mine sites throughout the United States, with employee populations ranging from 40 to 175. In exploring leaders’ perspectives on how they systematically manage health and safety, examples such as approaches to task training, handling near-miss incidents, identifying future leaders and providing workers with feedback offer insights into how leaders translate their knowledge and management of site-level risks to others.

Jan 1, 2017

By A. F. Cohen

When location guidelines are followed in choosing sites for fixed point velocity transducers for use in underground coal mine monitoring, mine air turbulence intensities <11% are generally expected at those sites. The objective of this Bureau of Mines investigation to determine the effect of turbulence intensities <11% on vortex shedding sensors and transducers. Measurements were made at velocity levels of interest for underground coal mine monitoring use (?200, ?500, ?1,000, ?1,500 ft/min). The effect of grid-produced turbulence intensities (2% to ?14%) on the output of vortex-shedding air-velocity transducers was less than ±10%.

Jan 1, 1985

By G. T. Krempasky

This report covers the installation and evaluation of lb reinforced concrete sets, 6 in each of 3 mines in the Goeur d&apos;Alene mining district, Shoshone County, Idaho, and is the second of a series to determine the feasibility of a more permanent type of mine support. Closure measurements, where applicable, were made periodically of the concrete-set installations and were compared to the initial cross section of the sets. A different method of blocking was used at each test site; at one test site the type of blocking was changed several times during the test. Results from each test site are reported separately. No attempt was made to compare the cost of the concrete installations with the cost of other types of support used in the district. Such an evaluation of permanent types of support would require a longer period of time. At this time, tests are not complete enough to determine the applicability of underground concrete supports. However, results to date tend to confirm the general opinion that precast concrete mine supports could be used to advantage in openings that require support and must have long life, especially where decay of timber is an important factor.

Jan 1, 1963

By Waddah Akili

At an offshore site along the Red Sea coast of Saudi Arabia, marine structures were supported on tubular steel piles driven into coral and coral contaminated sands and silts. Surprises and disappointments faced during the installation of the piled foundation were, to a large measure, due to inappropriate design methodology and absence of proper soil information. The paper describes the design evolution process, highlights the static pile test program conducted to verify design parameters, and amplifies the need to prepare for worst possible scenario when coral deposits are encountered. Despite corrections made to the design, based on site-specific insitu parameters (skin friction, end bearing) perceived from load tests conducted on site; the final design adopted overestimated capacities in over 50 percent of total piles driven. The paper describes the changes introduced to the design during the execution of the project, highlights the pile test program conducted to verify the design, and compares pile design penetration with actual penetration depth. The unpredictable and erratic pile behavior observed, ascertains the need for more appropriate pile design and installation guidelines for driven piles in coral and coral contaminated formations.

By S. J. Taylor

The siting, grading and fill usage for leach pads are important aspects of leach pad design. A method is presented that optimizes the cut and fill quantities (i.e. minimizes the cost) required to grade a leach pad with parallel cells; given the desired pad characteristics of maximum and minimum pad slopes, maximum cut and fill depths, etc. and the cut and fill costs. The method allows the variation of the cut and fill costs with depth, which allows the accurate modeling of the cost savings practice of using cheaper fill towards the bottom of a thick fill. This optimization could be incorporated into a CAD package, enabling a designer to simply draw a desired pad shape on a site plan, input the pad and heap characteristics (required heap volume, heap height, heap sideslopes, etc.) and then have the computer report both the adequacy of the pad area and the optimum grading for the particular pad shape. Using this, a designer could quickly and accurately assess the optimum, or cheapest, grading of many shapes and positions for a leach pad. This would be especially useful for large pads that need to be sited on rough terrain.

Jan 1, 1996

By Paul Hewitt, Aaron Rastall

The New South Wales South Coast rail corridor is key infrastructure for both freight and passenger transport. Geomorphological and geological evidence suggests that land instability has been widespread throughout sections of the rail corridor, long before the first documented record of landslide activity in 1879. Major landslides occurred along a 25-km length of the South Coast Railway connecting Sydney and Wollongong because of significant rainfall events of the late 1980s. Since this time, several sites have been identified as subject to instability and treated progressively under a risk priority and safety management system. Two such sites comprise a station footbridge and overhead wiring structure (OHWS), both founded on high embankments overlying colluvial materials resulting in the structures’ potential movement and associated stability concerns. This paper presents these two sites as case studies, and discusses the project geology, geotechnical models developed, interpretation of monitoring data, and successful remediation of the rail structures using sleeved bored piles. The sleeved pile system was used to isolate bored piles, which separated the bridge foundations and OHWS from the moving soil mass to ensure the piles can carry the rail structure loads, unaffected by downslope soil movements.

Nov 1, 2022