Deep Quarries Research Articles

Container technology for transporting rock masses in quarries

Container technology for transporting rock masses in quarries

Development of mining operations in deep quarries using automobile and combined transport

Aim of this paper is to explore the development of mining operations in deep quarries utilizing automobile and combined transport systems to overcome these challenges. The use of automobiles in mining has been a growing trend, offering flexibility, maneuverability, and increased productivity. In deep quarries, traditional automobile transport faces limitations in terms of reach and efficiency, combined transport systems incorporating a combination of automobiles, conveyor belts, and other transport mechanisms have been proposed. This paper discusses the advantages of automobile transport in deep quarries, including its ability to navigate narrow passages and transport smaller loads efficiently. It examines the integration of combined transport systems, which leverage the strengths of automobiles alongside other modes of transportation to optimize mining operations. Key considerations in the development of these systems include infrastructure design, vehicle specifications, safety protocols, and environmental impact. By implementing innovative solutions tailored to the specific challenges of deep quarry mining, such as automated vehicle control and monitoring systems, it is possible to enhance efficiency, reduce operational costs, and improve safety standards. Also, this paper highlights case studies and examples of successful implementations of automobile and combined transport systems in deep quarries around the world. These real-world examples demonstrate the feasibility and benefits of adopting such approaches in challenging mining environments. In the paper criteria requirements and recommendations for the implementation of this process are presented in the technological processes of compaction using separators, which are carried out during the construction of highways, and the interdependence of indicators is presented through tables, graphs and calculation expressions.

Study of the Influence of Damage Structures in Coal Seam Floors on the Damage of Small Hidden Faults

In order to study the catastrophe law of small hidden faults along the floors of deep quarries under the coupled conditions of high stress and strong seepage, this paper proposes a concept of damage structure that can replace the overall performance of a population of tiny fracture swarms within a non-homogeneous rock mass. Numerical simulation software is used to simulate and analyze the influence of damage structure on the evolution of surrounding rock, regarding its plastic zones, shear stress, and displacement, and the pore water pressure distribution in small hidden faults along coal seam floors. This study shows that under the influence of damage structure, the shear stress of the rock above the fault shows “N”-type change, the displacement of the surrounding area shows “S”-type change, and the shear stress of the rock below the fault and the pore water pressure above the fault show “M”-type change. The damage structure changes the performance of the coal seam floor’s water barrier by reducing the strength of the rock surrounding the fault, blocking the release rate of the shear stress of the surrounding rock, weakening the support pressure of the fault, reducing the degree of expansion of the surrounding rocks and shifting the direction of concentration of the pore water pressure. The results of this study can provide a reference for technology for water damage prevention and control of coal seam floors containing small hidden faults, under the influence of non-homogeneous rock bodies.

A technology for non-mining flanks formation at deep kimberlite open pits

Research objective is to develop a technology for non-mining flanks formation at deep open pits to reduce the amount of stripping operations and increase the scope of diamond fields mining by the open-pit method. Research relevance. The non-mining flanks formation and reduction of their additional excavation from the main openings is one of the most pressing problems in the development of deep kimberlite open pits. In the deep zone of kimberlite open pits, the stable slope of the flanks can reach 75°–80°, while according to the condition of ramps placement it is 48°–60°. This results in increased overburden volumes and limits the maximum depth of open pits. Methods of research. A technology has been developed for forming non-mining flanks and giving them a convex (cissoidal) profile with a gradual increase in slope angles. The technology consists in phased transition starting from a certain depth from the traditional overburden removal method to one with steeply inclined ramps and a spiral marginal tunnel passing behind the shear zone. A method for calculating the design angles of non-mining flanks when opening deep quarries with spiral ramps is substantiated. The main regularities of opening parameters effect on the slope angle of non-mining flanks are established. The results of experimental studies of rock physical and mechanical properties are used, as well as the methods of economic and mathematical modeling and technical and economic analysis. Results. By the example of Nyurba mine of Alrosa PJSC, it was found that the proposed technology allows increasing the resulting angle of non-mining flanks from 45°–48° to 54°–63°, reducing the amount of overburden removal operations by 3–8 times and effectively mining the open pit to a depth of 750 m corresponding to the depth of explored reserves. Scope of results. The proposed technology and method for calculating the design slope angles of non-mining flanks can be used not only in kimberlite open pit development, but also in the development of non-ferrous and precious metal deposits, represented by steeply dipping rounded deposits, by the open-pit method.

Substantiation of the optimal performance parameters for a quarry during the stage-wise development of steeply dipping ore deposits

The use of stage-wise schemes in the development of deep quarries is one of the ways to increase the economic efficiency of mining a deposit and determining the optimal stage parameters remains an urgent task. Such parameters are stage depth, bench height, block length, etc. However, there is a wide range of values for these parameters. Therefore, to select the optimal values and evaluate the effectiveness of design solutions, it is advisable to use the net present value, which is an international notion. As a result of the analysis of data on deposits, a large number of variable indicators can be identified that presumably affect the efficiency of mining. The article proposes to divide all parameters of the quarry mining into two types: mine engineering and economic. The importance of each of them is determined by the measure of influence on the net present value. Thus, to assess the measure of influence of mining indicators, the average values of each of them are taken, and as a result of the alternating change of one parameter under study, the measure of its influence on the discounted income received is estimated. The results of the analysis of relevant factors, their evaluation and comparative analysis are important indicators that significantly affect the design decisions made and the effectiveness of the investment project.

Подъемный ленточно-колесный конвейер с промежуточным цевочным приводом

Introduction. The article discusses the design of an improved belt-wheel conveyor with an intermediate pinion drive. The use of such a belt-wheel conveyor eliminates the need to use mobile crushing units and intermediate conveyor loading devices. The transfer of the drive from the end sprockets to the intermediate ones installed on the lifting section of the conveyor route significantly reduces the efforts in traction chains and running rollers and reduces the volume of mining and capital works. The introduction of a planetary differential mechanism between both drive sprockets ensures an even distribution of the traction load between both traction chains. At the same time, the possibility of misalignment of the running supports and the associated increased wear of the running rollers is excluded. Conveyor transport is the most effective means for lifting rock mass. The fundamental difference between belt-wheeled conveyors is the exclusion of rolling of the load-bearing belt along stationary roller supports. The joint movement of the conveyor belt and the closed loop with running supports provide the possibility of moving large-lump mining loads with piece sizes up to 1200 mm or more, which eliminates the need for secondary crushing of loads in mobile crushing units. The purpose of the research: the use of an improved belt-wheel conveyor with an intermediate pinion drive for the transportation of large-sized cargoes. Research methodology. A comparative analysis of the designs and parameters of lifting conveyors was carried out in order to ensure non-overloading lifting of loads from deep quarries with a further increase in depth. Research results and discussion. As a result of a comparative analysis of the conveyor designs and parameters, the most optimal variant of a belt-wheel conveyor with an intermediate pinion drive using a planetary differential mechanism was established. Conclusions: 1. Studies of the design of an improved belt-wheel conveyor with an intermediate pinion drive have been carried out. 2. It is established that the introduction of a planetary differential mechanism between both drive sprockets ensures an even distribution of the traction load between both traction chains. 3 It was found that the transfer of intermediate drives of lifting belt-wheel conveyors from the head end sprockets to the sprockets installed on the upper section of the bend of the conveyor route can significantly reduce the load on the traction chains and running rollers of the supports. 4. It is determined that the transfer of the drive from the end sprockets to the intermediate ones installed on the lifting section of the conveyor route significantly reduces the efforts in traction chains and running rollers and reduces the volume of mining and capital works. 5. It is confirmed that the introduction of a planetary differential mechanism between the shafts of the drive sprockets ensures a uniform distribution of the drive force between the two traction chains, excluding the possibility of misalignment of the running supports and the associated increased wear of the running rollers.

Задачи развития перспективных циклично-поточных технологий для глубоких карьеров

The development of open pits, both in terms of their mining intensity and a significant increase in the current and design depth, requires improvement of transport systems that form the bulk of the production cost. One of the most proven types of combined transport that provides high productivity is the truck-and-conveyor system. Therefore, this paper focuses on its adaptation to the future mining conditions (high dynamics of open pit mining development with creation of deep quarries, the need to reach open pit depths of up to 800–1200 m). The field of application of different types of transport is not static and changes along with the technical development of transport means, their introduction into mass production, and a change in the target group of mining and operating conditions. The article provides a systematization of open-pit transport applicable in modern conditions and shows the experience gained by the Institute of Mining of Ural branch of RAS in the in-pit crushing and conveying technology, mobile (semi-stationary) crushing and reloading plants and self-propelled crushing units. The results of calculations and technical and economic parameters of open-pit truck haulage and conveyor transport in a wide range of mining conditions are described. It is shown that an urgent research and engineering challenge is the development of technologies for the phased introduction of high-performance equipment for in-pit crushing and conveying transport to a great depth with a minimal additional extension of the open pit walls. At the same time, it is possible to use both steeply inclined and traditional belt conveyors, depending on the specific operating conditions. Conveyor transport is preferable for use at the main stage of the life cycle of deep quarries in terms of its efficiency and throughput, but its use is constrained by a number of factors considered in the paper.

Terrestrial photogrammetry at the quarry and validating the accuracy of slope models for monitoring their stability

The paper is devoted to the application of photogrammetry in surveying and geomechanical studies of the state of stability of slopes in a quarry. For deep quarries a particularly important task is to ensure the stability of the slopes of the benches. The purpose of this study is to improve the survey techniques of the slopes using terrestrial photogrammetry, the establishment of the values of the basic errors in the positioning of cameras in local geodetic network. The results of photogrammetric measuring data processing, which are the coordinates of the slope points and its elements, point cloud, surface model, volume and area data, improve the quality of geomechanical monitoring at mining enterprises and provide increase safety of mining operations. The proposed method of survey consists in positioning images (projection centres) in the system of the geodetic reference network by measuring with an electronic total station. Established during the study was dependence of the accuracy of the coordinates of the three-dimensional model of the slopes on the distance between the camera and the total station, between the camera positions in a pair of images. The article contains the results of the practical implementation of the proposed survey method, the results of experiments performed for the purpose of comparison with an alternative measurement method, which was a survey by a total station, graphs of dependencies describing the effect of measurement parameters on the accuracy of work performed. The article is also supplemented by a theoretical analysis of the use of UAVs in the use of work to determine of stability of slopes in a quarry, which is based on the authors’ experience with the use of UAVs in open pit mines. In this theoretical comparison, the emphasis is mainly on the operability of the use of UAV, which in the case of open pit mines creating a practically stable wind vortex with a speed higher than the allowed speed of operation rotors UAVs.

DEVELOPMENT OF THE MECHANISM OF ACTION OF DECONCENTRATED CHARGES OF VARIOUS SHAPES FOR VARIOUS MINING CONDITIONS

The modern requirements of the market economy and the increasing complexity of the field development conditions require new scientific and technical approaches in deep quarries and mines in the complex development of subsurface resources. As you know, the dominant mining paradigm in drilling and blasting is associated with the technique of drilling wells and boreholes of a circular shape (cavity) with the placement of explosives in it. However, in mining science and practice, the variety of mining conditions has long required the creation of methods for the destruction of rocks with an asymmetry in the distribution of explosion energy in space and its maximum concentration in certain directions. In this regard, we consider a conceptual direction based on a fundamentally new mechanism of action of the explosion of known groups of parallel-converged borehole charges, which effectively expand their use in various mining applications. The development of a new mechanism of action of the explosive process with the use of a computer program and numerical simulation of calculations made it possible to use the change in the shape and design of the charge as a means of increasing the share of the energy flow of the explosive explosion in a certain direction. The design of the deconcentrated charge is shown as a means of increasing the fraction of the energy flow of the explosive explosion in a given direction, which leads to a significant increase in the efficiency of the directed explosion and, in particular, minimizes its action in the opposite," legit", direction. Based on the results of the research, a method of blasting operations is proposed to neutralize the influence of anomalies in the state of the massif on mining operations by the explosive method. The method includes the appropriate tools, characterized by an unconventional design of the borehole charge and using a mechanism for influencing the anomalous states of the array with a combination of its explosive features.

Perspective trends for the development of cycle-flow technology in deep quarries taking into account the structure of their working area

Over the past 20 years, the parameters of the working zone of deep quarries have changed, which began to consist of sections of inclined and steep sides. At a number of deep iron ore quarries, temporary internal dumps of overburden rocks began to be created in the working area, which influences the choice of schemes for opening deep horizons in cyclic-flow technology (СFT). The purpose of the study is to substantiate promising directions for the development of CFT in deep iron ore quarries, taking into account the structure of their working area and the use of steeply inclined conveyors (SIC). It is shown that with certain parameters of a large piece transported by the conveyor belt, contained in the transported rock mass, and its certain kinetic energy, stable operation of the system, widely used steeply inclined and inclined conveyors, is achieved. The parameters of a steeply inclined conveyor when transporting rocks with a high density were determined. It is assumed that with the same kinetic energy of a piece (ore, rock) contained in the transported rock mass, stable operation of a steeply inclined conveyor will be ensured. Based on this, the parameters of the transported piece and the parameters of the steeply inclined conveyor are determined. According to the maximum size of the pieces that come after crushing in a cone crusher for coarse crushing on a steeply inclined conveyor, its stable operation is ensured at a density of transported rocks of not more than 2.8 t/m3. The economical use of SIC is achieved by combining the cyclic-flow technology with SIC and with the technology of pre-enrichment of ore in a quarry. For these conditions, the use of cyclic-flow technology with steeply inclined and inclined conveyors is justified. The structure of the working zone of a deep quarry with gentle and steep sides is considered. For these conditions, rational schemes for the opening of horizons with steep sides of the open pit and the use of temporary internal dumps was developed. The depth of the quarry, at which it is necessary to introduce a new opening scheme, was established. It is shown that the time of transition to the next opening scheme is significantly affected by the productivity of the quarry and the rate of decrease in mining operations.

Study on the influence of the deformation zones of the quarry sides on the rock mass movement

The article presents a study and analysis of the causes of deformation of the slopes and sides of the quarry indicates that the magnitude and nature of the deformation processes depend on the height of the ledge, the angle of slope of the slopes, the physical and mechanical properties, the lithological and structural features of the instrument array and the geodynamic activity of the fault zones. The influence of the deformation zones of the sides of the quarry on the transport of rock masses is justified. The zone of deformed masses of the ore deposit, which affect the movement of the rock mass, is studied. Each process performed in open pit mining is linked to another workflow. Without ensuring the safety of mining operations and performing the tasks set is impossible. Transportation of rock masses in the lower horizons of a deep quarry is one of the main tasks of the industry. At the same time, the removal of deformation and landslides in the area where the transport berm is being constructed for draining and continuous transportation is the main goal of the quarry. The stability of the transport berm depends directly on the stability of the side of the quarry. It is determined that the choice of a single-lane or twolane transport berm constructed for heavy-duty quarry dump trucks depends on the condition of the side of the quarry.

RESEARCH OF THE INFLUENCE OF TECHNOLOGICAL FACTORS ON THE STATE OF THE SIDES OF DEEP QUARRIES

The article considers the influencing technological factors of mining operations on the state of the quarry sides. In technological processes, the stability of the sides of rock and semi-rock rocks and the value of the angle of inclination of the sides is most affected by drilling and blasting operations. It is determined that effective technological schemes in the zone of residual deformations should be carried out taking into account the geological structure of the contour array. Changing the opening scheme is associated with the development system and mining mode. To ensure the safety of the sides of deep quarries, several variants of schemes, crevice formation in the contour zone and methods for controlling deformation processes are recommended.

Chrysotile asbestos ― raw materials of the construction industry from deep quarries

A ladle belt conveyor with increased traction ability is proposed at the request of Kostanay Minerals JSC. A geometric diagram of the conveyor route for cyclic-flow technology with the transportation of rock mass steeply falling conveyors in the contours of the quarry of the first stage of the Dzhetygara chrysotile deposit is given. The calculation of the geometric dimensions of individual sections of the conveyor is performed. The parameters of the transported material, the route and the bucket belt conveyor itself are determined.

Chrysotile Asbestos: Raw Materials for the Construction Industry from Deep Quarries

A bucket belt conveyor with increased traction ability is proposed at the request of Kostanay Minerals JSC. A geometric diagram of the conveyor circuit for the cyclical-flow technology with the transportation of rock mass by steeply inclined conveyors in the contours of the quarry of the first stage of the Dzhetygara chrysotile deposit is given. The calculation of the geometric dimensions of individual sections of the conveyor is performed. The parameters of the transported material, the circuit and the bucket belt conveyor itself have are determined.

Determining the capacity of a bunker as a part of the handling system with combined transport

Introduction. Significant share of the costs for deep quarries is the cost of rock mass reloading from the “assembly transport” to the main transport make up a considerable proportion in open pit development costs. Portable handling systems with bunkers are used, the parameters of which are determined by several methods. Methodology. In this work, when determining the capacity of the bunker, two approaches have been considered: deterministic – transport systems operate at nominal conditions; probabilistic – transport systems operate with their inherent unevenness. The methodology adopted is based on the geometry of the bunker in the configuration of the “inverted obelisk”, as the most productive system. Formulas to calculate the technological and geometric capacity of the bunker have been proposed. The proposed method parameters design takes into account assembly (automobile) transport arrival rate, which is described by the Poisson distribution and railway transport arrival rate described by the distribution of Erlang. Several numerical examples reveal practical application for bunker parameters determination. 112 "Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal". No. 4. 2020 ISSN 0536-1028 Results. The significance of the required additional bunker volumes has been justified in order to make up for cyclic transport vehicles irregular operation within combined transport complexes.

Новые технические решения по проветриванию глубоких карьеров

The paper discusses the issues of ventilating in deep quarries caused by the intensification of blasting operations at great depths, the increased distance of ore truck transportation to the daylight area, constant change in the geometrical parameters of the quarry, its microrelief and direction of mining, and increased isolation of the mined space from the environment. We provide a brief analysis of the current tools for forced airflow in deep quarries, which showed that the use of forced ventilation is often challenging since it leads to high energy consumption, high level of noise exceeding the permissible parameters, and high speeds of forced air flows may blow the dust off the quarry surfaces.The article presents methods and tools developed at the Siberian Federal University for intensifying the natural airflow in deep quarries by changing the air density at the entrance and exit points of the pit, as well as heating the shady areas using mirrors and solar energy, which do not interfere with mining and blasting operations.

Geocultural landscaping: Guidelines and conceptual framework to design future scenarios of exploited lands

The environmental recovery of quarried areas is increasingly a landscaping first-order issue in many countries and relevant lessons can be learned from each case history, depending upon factors such as the terrain nature and landscape consolidation over time. The case of the Tivoli travertine quarries near Rome (Acque Albule Basin, Italy) is addressed with a multidisciplinary approach and analytic data indicating sustainable and resilient future solutions. Geological data are analyzed to know the resources and natural hazards of this territory. Historical landscape analyses are next accomplished to know the cultural heritage and evolution of man-nature interactions. Eventually, the present land use and 3D landscape are considered to know the current setting. This territory is characterized by natural hazards including earthquakes, degassing, subsidence, and river flooding, and by resources such as abundant thermal waters. Historical analyses show the occurrence of a significant cultural heritage including two UNESCO world heritage sites. The present landscape is characterized by deep quarries and unplanned urbanization. The integration of geological data with historical information provides a new knowledge forming a geocultural database that must be taken into consideration for future planning. Based on these results, general landscape and urban guidelines are proposed for the future recovery of this intensively-quarried and -urbanized territory. The main lesson learned from the Tivoli case history is twofold: (1) the integration and feedback between multiple disciplines and professionals (architects and geologists) working together on environmental improvements and (2) the careful view of the past territory and meticulous analysis of existing buildings and urban landscapes are the key to sustainably interpret the future landscape. The main novelty of this lesson is the improvement of the concept of cultural landscape (UNESCO: http://whc.unesco.org/en/culturallandscape/) and its expansion toward geological issues and man-geology/nature interactions. In an urban-saturated territory that is also geologically-worn by human activities (e.g., Acque Albule Basin), restoring guidelines must comply with the partly-new concept of geocultural landscaping, which consists of a sustainable and resilient planning based on the study and understanding of natural-geological hazards, natural and cultural resources, and man-nature relationships over large spaces and long terms (4D). A general conceptual framework for geocultural landscaping is eventually proposed.

Исследование возможности применения конвейерного транспорта в сложных горно-геологических условиях глубоких высокопроизводительных карьеров

The conveyor transport will remain as one of the most perspective types of transport for high-performance deep quarries in the near future. This is due to its main advantages, such as high efficiency, relatively low cost of transportation of the rock mass, large-angle lifting the rock mass, and others. The modern inclined conveyers could convey the rock mass with different physical and mechanical properties from soft to roach rock with designed rake angle up to 90 degrees. From the perspective of open-pit mining and conveyance of the mined rock on the surface, conveyors are established from 16 degrees to the angle equaled to gradient of slope of spoil bank. At the same time, the placement of conveyor is implemented on spoil bank in a steep trench or foot pieces, mounted on the safety berms of rock and half-rock solids. However, such conditions conveyors accommodation is not suitable for complex geological conditions when the quarry side stacked unstable rocks. The paper presents the study on evaluating the possibility of establishing conveyor lift in complex mining and geological conditions of quarry.

An evaluation Zequanox® efficacy and application strategies for targeted control of zebra mussels in shallow-water habitats in lakes

An evaluation of Zequanox ® (a naturally derived biopesticide that is non-toxic to humans and other aquatic life and selectively kills dreissenid mussels) for controlling zebra mussel infestations in shallow-water habitats in lakes was conducted at Deep Quarry Lake in DuPage County, Illinois during summer 2012 and 2013. During the 2012 trial, three sets of paired 24-m² treatment and control sites were established within the lake, while a single 324-m² treatment site was established for the 2013 trial. Zequanox was applied to treatment plots, contained using PVC barrier curtains, and barriers were removed during the morning following application. Zebra mussel mortality and size distributions on natural substrates were assessed one day and one week post-treatment for 2012 trials and one day and two weeks posttreatment for 2013 trials; percent mortality of zebra mussels in mesh containers in treatment and control sites was also monitored up to 14 days and 48 days post-treatment in 2012 and 2013, respectively. Several water quality parameters were measured in control and treatment plots before and during application and up to 14 d post-treatment. Mean percent mortality for adult zebra mussels on natural and artificial substrates in treatment locations 7–48 d following Zequanox application ranged from 92–98% during both years, while mortality was consistently ≤10% in control locations. Mean percent mortality ranged from 15–76% in locations > 5 m from and in water shallower than Zequanox application points (<0.6 m depth) during the 2013 trial likely due to limited product dispersal into these areas. There was no significant difference in the size distribution of live and dead zebra mussels in treatment plots. Mean veliger mortality was 94.4% 20-h after the start of the 6-h Zequanox treatment period in the treatment area compared to 15.1% in untreated locations during the 2013 trial. Temporary but substantial reductions in dissolved oxygen were observed in treatment locations during the morning following Zequanox treatment in both 2012 and 2013 trials, likely due to the presence of the barriers that prevented well-oxygenated water from circulating into treatment zones from adjacent areas in the lake. Dissolved oxygen concentrations quickly rebounded to levels consistent with control sites upon removal of barriers. No effects of Zequanox treatment on ammonia, total nitrogen, total phosphorus, biochemical oxygen demand, chlorophyll a, pH, or conductivity were observed. Results suggest that Zequanox has potential as a tool for controlling zebra mussels in shallow-water habitats in lakes without significant long-term effects on water quality.

Effect of industrial explosions on the stability in rock mass with cavities

The paper substantiates the conditions of seismic stability in the rock mass with cavities, on which protected objects are located, under constant seismic effects of mass explosions in quarries. Based on the ray-tracing method, a mathematical model of the interaction between longitudinal and transverse waves with a spherical cavity has been developed. An algorithm has been elaborated for determining the total static and dynamic loads along the spherical cavity perimeter from seismic explosion waves falling on the interface. The regularities of joint action of static loads have been determined, when located above the objects cavity, with allowance for the effect of the mass of cavity ceiling, the mass of the protected object above it and dynamic loads in the rock mass, and under the plane wave front fall on the cavity from different directions. The dependences of the change of total stresses referred to the incident wave stress at the interface of the rock mass and the cavity depending on the coordinate on its surface have been set. It has been established that the most dangerous points of cavity surface, in which destruction is likely to occur, are the cases when the seismic wave front falls on the cavity from the bottom directions typical for blasting operations in deep quarries. Under the arbitrary angles of the wave incidence on the cavity the stresses rearrange along the perimeter, which under different circumstances might lead to the mass breach and the fall of the protected objects, located above it, under the ground