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Number of results: 19
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Abstract

This paper offers a comparison of Muriella decolor specimens from different geographical regions and habitats (limestone caves in Poland and ice denuded areas near the Ecology Glacier, King George Island, South Shetland Islands, West Antarctic). Morphological and cytological variability, ecology and life strategies of M. decolor were studied in fresh samples, and also in cultures grown on agar plates. The complete life cycle, with de − tailed ultrastructural (LM and TEM) analysis are presented. The electron microscopic observations prove that materials identified as M. decolor collected in Poland and the Antarctic have distinct ultrastructural features. These include the chloroplast lamella arrangement, mitochondrial cristae structure and the cell wall thickness.
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Authors and Affiliations

Maria Olech
Joanna Czerwik-Marcinkowska
Andrzej Massalski
Anna Wojciechowska
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Abstract

The shrine antechamber is a standard component of the Indian temple architecture. It was originated in the Buddhist context, and the context was the rock-cut architecture of the Deccan and central India. The first antechamber was attempted in circa 125 CE in the Nasik Cave 17. It was patronised by Indrāgnidatta, a yavana , who possibly hailed from Bactria. The second antechamber was created in Bāgh Cave 2 in ca. late 466 CE. The patron remains unknown. The third antechamber was initiated in Ajanta Cave 16 within a few months. It was patronised by Varāhadeva, the Prime Minister of Vākātaka Mahārāj Hari Sena. When the third antechamber was only half excavated, the plan was cancelled by the patron himself due to a sudden threat posed by the Alchon Hūns led by Mahā-Sāhi Khingila. The Nasik antechamber was inspired from Bactria, the Bāgh antechamber was inspired from the parrallels in the Greater Gandhāra region, whereas the Ajanta Cave 16 antechamber was inspired from Bāgh Cave 2.

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Authors and Affiliations

Rajesh Kumar Singh
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Abstract

The article presents a methodology for determining the value of the expansion coefficient of a reconsolidated caving zone in the context of forecasting the rise in underground mine water levels and consequent surface subsidence caused by the process of flooding the closed coal mines. The paper also provides a brief characterisation of analytical predictive models regarding surface subsidence during the process of flooding coal mines. In order to describe the vertical deformation of the reconsolidated porous rock mass in the caving zone, a linear-elastic medium of Biot was utilised. The conducted theoretical calculations demonstrate a high agreement with the results obtained through the identification of the expansion coefficient parameter based on the analysis of in-situ subsidence measurements in Dutch and German mining areas. The proposed methodology was applied to a real case study involving the forecasting of the impact of the flooding process on the underground workings of the German Ibbenbüren mine. The article constitutes a significant contribution to the field of forecasting the rise in underground mine water levels and surface subsidence during the process of flooding closed coal mines. The presented methodology and obtained results can be valuable for researchers, engineers, and decision-makers involved in the planning and management of mining areas.
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Authors and Affiliations

Rafał Misa
1
ORCID: ORCID
Mateusz Dudek
1
ORCID: ORCID
Anton Sroka
1
ORCID: ORCID
Krzysztof Tajduś
2
ORCID: ORCID
Dawid Mrocheń
1
ORCID: ORCID

  1. Strata Mechanics Research Institute, Polish Academy of Science, Krakow, Poland
  2. AGH University of Science and Technology, Krakow, Poland
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Abstract

At the end of 2018, when the Hučivá Cave (Hučivá diera, Rausch Keller) was explored in Tatranská Lomnica, profile deposits in rear areas of the cave were found disturbed by an amateur excavation. One stone artefact was first found in back-dirt clay-layer material at the excavation pit, later joined by four more specimens from the cleaned pit profile. The Typological analysis of the artefacts shows, that their closest parallels are found in inventories of the Magdalenian culture. Hučivá is the only cave in the whole Tatras with documented prehistoric settlement and the only Slovak cave with evidence of the Magdalenian culture. The discovery provides new information concerning subsistence strategies of late Pleistocene hunters in High Tatra Mountain landscapes. In light of this discovery, the possibility of seasonal movements along the northern slopes of this mountains range to the east and then south, through the mountain passes to the upper Spiš region should now be considered.

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Authors and Affiliations

Paweł Valde-Nowak
Marián Soják
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Abstract

In recent years, many scientific and industrial centres in the world developed a virtual reality systems or laboratories. The effect of user “immersion” into virtual reality in such systems is largely dependent on optical properties of the system. In this paper, problems of luminance distribution uniformity in CAVE-type virtual reality systems are analyzed. For better characterization of CAVE luminance nonuniformity corner and edge CAVE nonuniformity were introduced. Based on described CAVE-type virtual reality laboratory, named Immersive 3D Visualization Lab (I3DVL) just opened at the Gdansk University of Technology, luminance nonuniformity of the system is evaluated and discussed. Data collection of luminance distribution allows for software compensation of intensity distribution of individual images projected onto the screen (luminance non-uniformity minimization) in the further research.

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Authors and Affiliations

A. Mazikowski
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Abstract

The paper is focused on the palaeographic development of the western part of the Holy Cross Mountains, Poland, during the maximum extent of the Sanian 2 (MIS 12) ice sheet and its retreat. The studies were based on archival cartographic data, coupled with new lithological and petrographic analyses of limni- and fluvioglacial sands, i.e., grain-size composition, quartz grain morphology and heavy mineral analysis, as well as analysis of the erratic material of tills. The results confirm the regional variability of the erratic material in the Sanian 2 tills and point to the long-term development of fluvioglacial sands cover documenting cold climate conditions. They also evidence that the western part of the Holy Cross Mountains was the area where two oppositely directed ice sheet lobes (Radoszyce and Sandomierz) advanced during the Sanian 2 Glaciation and that deglaciation of the area took place in two stages. Huge quantities of meltwater released at that time contributed to the intensification of earlier initiated karst phenomena, as well as filling of the existing caves by fluvioglacial sands.
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Authors and Affiliations

Jan Dzierżek
1
Leszek Lindner
1
Krzysztof Cabalski
1
Jan Urban
2
Michał Cyglicki
3

  1. Faculty of Geology, University of Warsaw, Żwirki i Wigury 93, PL-02-089 Warszawa, Poland
  2. Institute of Nature Conservation, Polish Academy of Sciences, Adama Mickiewicza 33, PL- 31-120, Kraków
  3. Polish Geological Institute-National Research Institute, Rakowiecka 4, PL-00-975, Warszawa, Poland
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Abstract

Loess is an important component of cave deposits. Loess and loess-like strata in caves and rock shelters may serve as stratigraphic correlative units and paleoclimate indicators. For the Polish Jura (southern Poland), one of the key regions of cave deposits studies in Europe, the published information concerning the stratigraphic importance of loess is limited to the sequences from around the Last Glacial Maximum (LGM). In this paper, a review of the archival data about loess deposits situated below the LGM strata in caves and rock shelters of the Polish Jura is presented. The paper discusses the occurrence, lithology, stratigraphy, chronology and paleoecology of the pre-LGM cave loess. The most important sites of the pre-LGM cave loess in the region include: Biśnik Cave, Nietoperzowa Cave, Mamutowa Cave, and Ciemna Cave (only the outer zones). The loess strata in these sites correlate with cold Marine Isotope Stages (MIS): mid-3, 4, 5b–d, 6, and possibly 10. They represent all the main facies of cave loess: typical eolian loess, colluviated loess-like deposits, loess with bedrock debris, and loams of complex grain-size composition but with the predominance of a loess component. Stratigraphic correlations with loess-paleosol sequences are proposed.
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Authors and Affiliations

Maciej T. Krajcarz
1

  1. Institute of Geological Sciences, Polish Academy of Sciences, Twarda 51/55, 00-818 Warszawa, Poland
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Abstract

In order to study the sensitivity of multiple karst cave factors on surface settlement during Tunnel Boring Machine(referred to TBM hereinafter) tunnelling, a three-dimensional numerical model is built by taking a subway project as an example and combining MIDAS GTS NX finite element software. Secondly, the influence of the radius, height, angle, vertical net distance, and horizontal distance of the karst cave on the maximum surface settlement is studied and sorted under the two working conditions of treatment and untreated using the grey correlation analysis method. Additionally, a multi-factor numerical model of the untreated karst cave is established. Finally, based on the preceding research, a multi-factor prediction model for the maximum surface settlement is proposed and tested. The results reveal that when the karst cave is not treated, the radius and height of the karst cave have a significant effect on the maximum surface settlement. After the cave treatment, the influence of the cave parameters on the maximum settlement of the surface is greatly reduced. The calculating modelcreated in this study offers excellent prediction accuracy and good adaptability.
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Authors and Affiliations

Bichang Dong
Tao Yang
ORCID: ORCID
Binbin JU
Zhongying QU
Chao Yi
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Abstract

An important source of palaeoecological and palaeoenvironmental information is intra-specimen variability of isotopic composition of mammal tooth enamel. It reflects seasonal or behavioral changes in diet and climate occurring during a life of the animal. While well-known in ungulates, in carnivorans this variability is poorly recognized. However, carnivoran remains are amongst the most numerous in the Pleistocene fossil record of terrestrial mammals, so their isotopic signature should be of particular interest. The aim of the study was to verify if enamel of a fossil cave hyena (Crocuta crocuta spelaea) and a cave bear (Ursus ingressus) records any regular inter- or intra-tooth isotopic variability. We examined intra-individual variability of δ13C and δ18O values in permanent cheek teeth enamel of fossil cave hyena and cave bear from the site of the Perspektywiczna Cave (southern Poland). We conclude that the isotopic variability of the cave hyena is low, possibly because enamel mineralization took place when the animals still relied on a uniform milk diet. Only the lowermost parts of P3 and P4 enamel record a shift toward an adult diet. In the case of the cave bear, the sequence of enamel formation records periodic isotopic changes, possibly correlating with the first seasons of the animal life.

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Authors and Affiliations

Michał Czernielewski
Magdalena Krajcarz
Maciej T. Krajcarz
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Abstract

Bisnik Cave is an important site of Middle Palaeolithic, with the longest sequence of Neanderthal settlement phases in Central Europe. In the previous studies of the Bisnik sediments, different elements of palaeoenvironment in the periods of Neanderthal occupation have been recognised, except of palaeovegetation, which could not be derived because of lack of preserved plant micro- or macrofossils. The current work is an attempt to reconstruct palaeovegetation in vicinity of the Bisnik Cave, using analysis of composition of plant-derived n-alkanes, preserved in sediments. In our study, we analyzed one sample from each of the sediment's layers 11 - 19c (early Late Pleistocene and late Middle Pleistocene). Abundant n-alkanes (mostly n-C27, n-C29 and n-C31) were found in all the sampled layers except for the layers 12, 16 and 19d, showing no alkanes at all. There is clear diversification of n-alkanes composition and cpr (carbon preference index) values between layers. Analysis of this composition, allows us to claim that the layers 11 and 14 were accumulated when the cave's vicinity was covered by dense coniferous forests, hence upon warm climate. The layers 19, 19a lower, 19b and 19c, presumably originated during cold periods when open woodlands or grasslands dominated. The other analyzed layers could be counected with intermediate vegetation in form of open woodland. However, not all of the achieved results stay in compliance with the actual stratigraphy, established basing on lithological data and palaeoecology offossil fauna, and we hope that explanation of this discrepancy would be possible after more extensive studies of molecular fossils are done.

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Authors and Affiliations

Maciej T. Krajcarz
Marek R. Gola
Krzysztof J. Cyrek
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Abstract

The article presents the approach to the design process of acoustic panels based on the scientific research. This approach is based on combining the technical and the design competences to develop the innovative product value for the concept of acoustic panels. The article presents the concepts of two new acoustic panels – an absorbing and scattering panel and a panel reflecting sound waves. The first part of the article presents the starting point for the presented project – the acoustic research and the inspiration for both types of presented solutions. Next, the materials possible to use were discussed, which could reproduce the natural acoustic properties of the lava and glacier caves. The next part presents consecutive stages of the product development in a modern form, ensuring the expected acoustic properties. The last part of the article presents a fully functional solution and proposes further research and development directions.
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Authors and Affiliations

Bartłomiej Borkowski
1
Katarzyna Suder-Dębska
2
Jerzy Wiciak
1
Anna Maria Szlachta
3

  1. Department of Mechanics and Vibroacoustics, AGH – University of Science and Technology, Kraków, Poland
  2. Department of Power Systems and Environmental Protection Facilities, AGH – University of Science and Technology, Kraków, Poland
  3. Faculty of Industrial Design, Jan Matejko Academy of Fine Arts, Kraków, Poland
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Abstract

Sublevel caving (SLC) mining method has several features that make it one of the preferred methods for ore extraction due to its high productivity and early access to ore recovery. However, there are some major challenges associated with the SLC method such as ground surface subsidence, high unplanned ore dilution, and the potential for air blast. To remedy these shortcomings, a recent approach has been to modify the SLC method by introducing rockfill into the void atop the production zone to provide continued support for the host rock and prevent it from caving. This paper discusses in detail the merits of the Modified SLC or MSLC. In comparison with other long-hole stoping methods that are predominantly practiced in metal mines, the MSLC method boasts several advantages. Early production achieved from the topmost level helps reduce the payback period. Productivity is enhanced due to multilevel mining without the use of sill pillars. The cost of backfilling is significantly reduced as there is no need for the construction of costly backfill plants. Continuous stoping is achieved without delays as mining and backfilling take place concurrently from separate mining horizons. A significant reduction in underground development costs is achieved as fewer slot raises and crosscuts are required for stope preparation. These merits of the Modified SLC method in steeply dipping orebodies are discussed by way of reference to real-life mine case studies. Dilution issues are addressed, and the benefits of top-down mining are explained. Typical mine design, ventilation, materials handling, and mining schedules are presented. Geomechanics issues associated with different in-situ stress environments are discussed and illustrated with simplified mine-wide 3D numerical modeling study.
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Authors and Affiliations

Kenneth K. Adams
1
ORCID: ORCID
Tuo Chen
1
ORCID: ORCID
Atsushi Sainoki
2
ORCID: ORCID
Hani S. Mitri
1
ORCID: ORCID

  1. McGill University, Canada
  2. Kumamoto University, Japan
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Abstract

The draw theory is the foundation for decreasing ore loss and dilution indices while extracting deposits from mines. Therefore, research on draw theory is of great significance to optimally guide the draw control and improve the economy efficiency of mines. The laboratory scaled physical draw experiments under inclined wall condition conducted showed that a new way was proposed to investigate the flow zone of granular materials. The flow zone was simply divided into two parts with respect to the demarcation point of the flow axis. Based on the stochastic medium draw theory, theoretical movement formulas were derived to define the gravity flow of fragmented rocks in these two parts. The ore body with 55° dip and 10 m width was taken as an example, the particle flow parameters were fitted, and the corresponding theoretical shape of the draw body was sketched based on the derived equation of draw-body shape. The comparison of experimental and theoretical shapes of the draw body confirmed that they coincided with each other; hence, the reliability of the derived equation of particle motion was validated.

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Authors and Affiliations

Xiufeng Zhang
Ganqiang Tao
Zhonghua Zhu
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Abstract

In the extra-thick coal seams and multi-layered hard roofs, the longwall hydraulic support yielding, coal face spalling, strong deformations of goaf-side entry, and severe ground pressure dynamic events typically occur at the longwall top coal caving longwall faces. Based on the Key strata theory an overburden caving model is proposed here to predict the multilayered hard strata behaviour. The proposed model together with the measured stress changes in coal seam and underground observations in Tongxin coal mine provides a new idea to analyse stress changes in coal and help to minimise rock bursts in the multi-layered hard rock ground. Using the proposed primary Key and the sub-Key strata units the model predicts the formation and instability of the overlying strata that leads to abrupt dynamic changes to the surrounding rock stress. The data obtained from the vertical stress monitoring in the 38 m wide coal pillar located adjacent to the longwall face indicates that the Key strata layers have a significant influence on ground behaviour. Sudden dynamically driven unloading of strata was caused by the first caving of the sub-Key strata while reloading of the vertical stress occurred when the goaf overhang of the sub-Key strata failed. Based on this findings several measures were recommended to minimise the undesirable dynamic occurrences including pre-split of the hard Key strata by blasting and using the energy consumption yielding reinforcement to support the damage prone gate road areas. Use of the numerical modelling simulations was suggested to improve the key theory accuracy.

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Authors and Affiliations

Zhijie Zhu
Yunlong Wu
Jun Han
Ying Chen
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Abstract

Landslide is a common geological disaster which causes huge losses to people’s properties and national economic development. How to prevent and control landslides has become an important issue. This article introduces the geological and geographical environment of the landslide body, analyzes the basic characteristics of the landslide, calculates the landslide stability based on the ultimate equilibrium theory-based transfer coefficient method, discusses the development trend of the landslide and comes up with corresponding control schemes by taking the landslide body of Black Bovine Cave Copper Ore Mining & Beneficiation Project as example. It is found that the control scheme – “anti-slide pile + retraining wall + baffle + anchor cable” can be used to effectively prevent and control the geological disaster according to calculation. The study results can provide a reference for landslide body control.
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Authors and Affiliations

Hanhui Wu
1
ORCID: ORCID

  1. Civil Engineering, School of Civil Engineering, Chongqing Chemical Industry Vocational College, 400020 Chongqing, China
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Abstract

There are several large karst caves at haunch part of the Lidong Tunnel during construction, together with inrush water due to high pressure within these caves. In light of it, this paper takes YK342+113 section as an example and adopts finite difference software FLAC 3D, so as to analyze tunnel deformation when crossing karst caves under six different working conditions, including with or without karst cave, before and after karst treatment, along with support locations. According to analysis results: First, the wall rock mainly had deformation at tunnel vault when evacuating at the third bench, which is a critical monitoring focus for tunnel construction; Second, karst cave treatment contributed to better conduct forces on both sides of wall rock, thus reducing vault settlement, while not affecting horizontal convergence and upturn of vaults; Third, treatment measures were proved to be effective in minimizing wall rock deformation by comparing deformation curves under different conditions; Fourth, after treatment measures, the angular points within the cave’s chamber had stress concentration, which might cause secondary collapse. Field monitoring data revealed that the final settlement of the tunnel vault was relatively consistent with the numerical analysis results, with a distinct change in daily settlement after initial support construction. By integrating numerical analysis and field monitoring, the rationality of the karst treatment plan was fully verified, providing a valuable reference for similar projects.
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Authors and Affiliations

Kai Zhu
1
ORCID: ORCID
Kui Zhang
2
ORCID: ORCID
Xiang-Dong Wu
3
ORCID: ORCID
Xiang-Ge Chen
4 5
ORCID: ORCID

  1. Guangdong Nanyue Transportation Investment and Construction Co., Ltd, Guangzhou 510199, China
  2. Shenzhen ExpresswayOperation andDevelopmentCo., Ltd, Shenzhen 518110,China
  3. Poly ChangDa Engineering Co., Ltd, Guangzhou 510620, China
  4. Chongqing Jiaotong University, School of Civil Engineering, Chongqing 400074, China
  5. State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing 400074, China
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Abstract

The objective of this paper is a review of data on reconstruction of the Pleistocene palaeogeography (environment) and stratigraphy based on studies of karst sites in the Świętokrzyskie (Holy Cross) Mountains. Although the number of known Pleistocene karst sites in this region is small, the investigations of them have played a crucial role in a research of the Pleistocene. The study of the Kozi Grzbiet site provided the first evidences for new climatostratigraphy and classification of glaciations in Poland. The explanation of genesis of cryogenic calcite crystals discovered in Chelosiowa Jama-Jaskinia Jaworznicka cave system started a new direction of palaeoenvironmental reconstructions of the last glacial period. Kadzielnia palaeontological site was one of the first Early Pleistocene fossil assemblages in karst studied in Poland, whereas Raj cave provided abundant palaeontological and archaeological material from the Last Glacial. Other sites are of less scientific importance, however some of them can be used in education and popularisation of geosciences. Small number of already studied sites does not exclude discoveries of next sites of high scientific importance.

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Authors and Affiliations

Jan Urban
Helena Hercman
Katarzyna Ochman
Andrzej Kasza
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Abstract

Analysis of weathering parameters of bones from cave deposits is presented as a useful tool of palaeoenvironmental reconstruction. As an example, we studied profiles of sediments in two Palaeolithic sites: Nietoperzowa Cave and Deszczowa Cave. Our studies included histological and EDS analyses of bone remnants found in these profiles. This method allowed us to reconstruct the changes of palaeotemperature and palaeohumidity, and finally the climatostratigraphy of sediments. The results presented here put a new light onto the stratigraphy of Deszczowa Cave's filling. In particular, besides the Vistulian sediments (MIS 2-5d), we confirmed the presence oflayers formed during the Penultimate Glaciation (MIS 6) and Eemian Interglacial (MIS 5e).

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Authors and Affiliations

Maciej T. Krajcarz
Teresa Madeyska
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Abstract

The caving effect of the top coal caving is crucial for efficient mining. Using the Yushuling coal mine, Xinjiang province, China, as a case study, the coal and rock physical and mechanical parameters, such as the compressive, tensile, and shear strength values and hardness of the top coal and roof rock, were determined. The analysis of the effect of different factors on the blasting presplitting process was numerically simulated, and the optimal parameters of blast drilling were identified. Three presplit boreholes were implemented: in the workface, the workface’s advance area, and the two roadway roofs in the workface’s advance area. The optimal blasting drilling parameters and charge structure were designed. The field test results in the mine under study indicated that the top coal recovery rate of the 110501 fully mechanised top coal caving face was improved twice (from 40 to more than 80%), and an effective blasting presplitting was achieved. The proposed blasting presplitting method has an important guiding significance for fully mechanised top coal caving mining in Xinjiang and similar mining areas.
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Authors and Affiliations

Qiang Sun
1
ORCID: ORCID
Chengfang Shan
2
ORCID: ORCID
Zhongya Wu
1
ORCID: ORCID
Yunbo Wang
1
ORCID: ORCID

  1. China University of Mining and Technology, China
  2. Kuqa Yushuling Coal Mine Co., Ltd, Kuqa, Aksu, China

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