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Date submitted2023-06-01
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Date accepted2024-03-05
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Date published2024-08-26
Analyzing friction bolts load bearing capacity in varying rock masses: an experimental study in Anti Atlas Imiter silver mining region, Morocco
This study analyzes how key factors impact friction rock bolt capacity using standard pull-out tests, focusing on 39 mm diameter, 180 cm long split-tube bolts. We investigate bolt performance dependence on rock mass rating (RMR), time after installation, schistosity orientation, surface roughness, and installation quality. The aim is optimizing bolt design and implementation for enhanced underground stability and safety. Results show RMR strongly exponentially correlates with pull-out resistance; higher quality rock masses increase capacity. Anchorage capacity significantly rises over time, especially for RMR above 70. Increasing angle between bolt axis and rock foliation from 0 to 90° boosts pull-out response. Reducing borehole diameter below bolt diameter grows bolt-ground friction. Empirical models estimate load capacity based on RMR, time, orientation, diameter, roughness and installation quality. These reliably predict bolt performance from site conditions, significantly improving on basic RMR methods. Experiments provide practical friction bolt behavior insights for typical rock masses. The data-driven analysis ensures models are applicable to actual underground scenarios. This enables tailored optimization of bolting configurations and supports. Methodologies presented should improve safety, efficiency and cost-effectiveness of reinforced mining and tunneling. Overall, this study fundamentally furthers friction bolt performance understanding, enabling superior underground support design.
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Date submitted2020-07-02
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Date accepted2021-02-16
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Date published2021-04-26
Development of viscoelastic systems and technologies for isolating water-bearing horizons with abnormal formation pressures during oil and gas wells drilling
Article provides a brief overview of the complications arising during the construction of oil and gas wells in conditions of abnormally high and abnormally low formation pressures. Technological properties of the solutions used to eliminate emergency situations when drilling wells in the intervals of catastrophic absorption and influx of formation fluid have been investigated. A technology for isolating water influx in intervals of excess formation pressure has been developed. The technology is based on the use of a special device that provides control of the hydrodynamic pressure in the annular space of the well. An experiment was carried out to determine the injection time of a viscoelastic system depending on its rheology, rock properties and technological parameters of the isolation process. A mathematical model based on the use of a special device is presented. The model allows determining the penetration depth of a viscoelastic system to block water-bearing horizons to prevent interformation crossflows and water breakthrough into production wells.
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Date submitted2018-01-04
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Date accepted2018-03-08
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Date published2018-06-22
Influence of mining-geological conditions and technogenic factors on blastholes stability during open mining of apatite-nepheline ores
- Authors:
- M. N. Overchenko
- S. A. Tolstunov
- S. P. Mozer
The paper presents the results of borehole stability research and considers possible causes of emergencies. The features of the blast hole drilling process are analyzed taking into account the properties of the rock. Based on the distribution of speed of drill fines removal from the well, an algorithm for selecting drilling modes is proposed. The nature of change in the size of the holess over time has been analyzed. This paper investigates the influence of rock fracturing and its water content on borehole stability. Possible options for eliminating the man-made impact on the massif near holes and options for fixing the hole walls with soft shells are suggested. The experimental data on the installation of shells for the conditions of open mining of apatite-nepheline ores are given. The operability and effectiveness of the technology is proved.
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Date submitted2009-08-13
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Date accepted2009-10-30
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Date published2010-02-01
Reducing losses ore between whole chamber for the design of lower layers mine by Gubkin of open joint-stock company «Industrial complex KMAruda»
- Authors:
- E. I. Boguslavskiy
- P. V. Korzhavykh
Technological decisions on decrease in losses of ore in between chamber walls are considered at designing of the bottom horizons of mine of Gubkin. It is offered two variants of decrease in losses of the ore technologically compatible with each other for their simultaneous use. Results of calculation of losses of ore and economic consequences are resulted. The basic actions which are necessary for carrying out, before introduction of technological decisions in manufacture are described.
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Date submitted2009-07-24
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Date accepted2009-09-27
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Date published2010-04-22
Influence of geomechanical processes in rock mass on the selection of parameters of technological schemes for flat seams mining at the Leninsk-Kuznetsk coal deposit
- Authors:
- E. P. Yutiaev
The article deals with the aspects concerning the influence of geomechanical processes in rock mass on the selection of parameters of technological schemes for flat coal seams mining. Based on the analysis of experience gained under similar conditions at coal mines of the advanced national and foreign countries, the promising trends in the research work and development projects for the SUEK-Kuzbass Co.were suggested.
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Date submitted2009-07-29
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Date accepted2009-09-15
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Date published2010-04-22
Preconditions for application of supports of different types in productive workings of low-thick gently-pitching deposits in tectonically stressed massif (for conditions of the Karnasurt ore mine)
- Authors:
- A. V. Lovchikov
- A. V. Matytsyn
The paper presents the data on the mining-geological conditions for mining and types of stope supports applied at the Karnasurt Mine, the Lovozersky rare-metal deposit. The peculiar feature of mining conditions is the presence of high subhorizontal tectonic stresses in the rock masses, which make the stope roofs more stable, allowing application of non-reinforced types of support.