• Journal of the speleological society of Korea
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• no.8
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• pp.65-76
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• 1998

This article is based upon a talk given at the 1983 National Caving Conference explaining the types of personal computers available, their main features and how they could be used in connection with caving. There may be two groups of readers particularly interested in this subject, those covers with use of a computer who want some ideas on using it and others who want to know if getting a computer to use in connection with caving might be worth their while.

• Journal of the speleological society of Korea
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• no.4
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• pp.59-66
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• 1996

This article is based upon a talk given at the 1983 National Caving Conference explaining the types of personal computers available, their main features and how they could be used in connection with caving. There may be two groups of readers particularly interested in this subject, those covers with use of a computer who want some ideas on using it and others who want to know if getting a computer to use in connection with caving might be worth their while.

• Journal of the Speleological Society of Korea
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• no.90
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• pp.27-33
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• 2009

There are many caves in this country. distributionCaving can be recognized as a sport tourism resources. Caving is including a physical and spiritual discipline. Caves is expected to develop as a sports tourism resource.

• Steel and Composite Structures
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• v.48 no.1
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• pp.103-111
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• 2023

The caving property of top coal is a key factor to the success of top coal caving mining. The influence law of cyclic loading and unloading of hydraulic support on top coal caving is of great significance to improve the recovery rate of top coal. The similar simulation methods were used to study the dynamic evolution of the top coal cracks under the multi-cycle action of the support, and the parameters of top coal cracks were analyzed quantitatively in this paper. The results show that the top coal cracks can be divided into horizontal cracks and vertical cracks under the cyclic loading and unloading of the support. With the increase of the times of the support cycles loading and unloading, the load on the support decreases, the fractal dimension of the cracks increases, the number and total length of the top coal cracks increases, and the top coal caving is getting better. With the increase of the times of multi-cycle loading and unloading, the fractal dimension, total crack length and crack rate of top coal show a trend of rapid increase first and then increase slowly. Both the total length of the top coal cracks and the crack rate basically show linear growth with the change of the fractal dimension. The top coal caving can be well improved and the coal resource recovery rate increased through the multi-cycle loading and unloading.

• Tunnel and Underground Space
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• v.14 no.5
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• pp.305-317
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• 2004

Due to the steep and narrow characteristic of domestic coal beds, the slant chute caving or sub-level caving method have been mainly adopted in Korea, whereas the long-wall mining has been widely used all around world. However, the slant chute caving or sub-level caving method have disadvantage of not giving much information on the scale and characteristic of abandoned mines. Hence, those information on the abandoned mines in Korea are not easily available. In this study, based on the characteristic investigation of the domestic mining methods, the geological survey and safety analysis were carried out for Donghae highway section 2. Finally, the optimum ground reinforcement methods for that site were selected.

• Journal of the speleological society of Korea
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• no.4
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• pp.69-78
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• 1996

During the year and a half of preparation for the Untnmed Ri Expedition (Caves $ Caving 29 p. 29) a lot of time was devoted developing the techniques we would use to explore the roaring wh waters of Nare. We finally left for New Britain with a whole new set caving rules and hardware which would not be out of place in an Indi Jones movie. The first serious work to tackle this new problem in caving wa pioneered by the French in 1978 after the discovery of the Nare. M and Kavakuna - all big river caves with flows of 15-20 cumes. We tir out these techniques on the white water rivers of north Wales. ma some improvements and tested some new ideas. This articles is a summary of our research and experience.

• Journal of the speleological society of Korea
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• v.10
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• pp.61-70
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• 1999

• Geomechanics and Engineering
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• v.19 no.3
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• pp.269-282
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• 2019

Due to top-coal and immediate roof as cushion layer connecting with support and overlying strata, it can make significant influence on strata behaviors in fully mechanical top-coal caving working face (TCCWF). Taking Qingdong 828 working face as engineering background, $FLAC^{3D}$ and $UDEC^{2D}$ were adopted to explore the influence of top-coal thickness (TCT), immediate roof thickness (IRT), top-coal elastic modulus (TCEM) and immediate roof elastic modulus (IREM) on the vertical stress and vertical subsidence of roof, caving distance, and support resistance. The results show that the maximum roof subsidence increases with the increase of TCT and IRT as well as the decrease of TCEM and IREM, which is totally opposite to vertical stress in roof-control distance. Moreover, although the increase of TCEM and IREM leading to the increase of peak value of abutment pressure, the position and distribution range have no significant change. Under the condition of initial weighting occurrence, support resistance has negative and positive relationship with physical parameters (e.g., TCT and IRT) and mechanical properties (e.g., TCEM and IREM), respectively.

• Geomechanics and Engineering
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• v.9 no.2
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• pp.195-205
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• 2015

Barricade failures generally occur at the early times of paste backfill when it is fresh in the stopes. The backfill strength increases and need for barricading pressure decreases as a result of the hydration reactions. In this study, paste backfill barricades of Cayeli copper mine were investigated to design cemented mineral processing plant tailings as barricade body concrete. Paste backfill in sub-level caving stopes of the mine needs to be barricaded for only four or five days. Therefore, short term strength and workability tests were applied on several cemented tailings material designs. Barricade failure mechanisms, important points of barricade designing and details of the new concrete material are explained in this work. According to the results obtained with this experimental study, the tailings were assessed to be used in concrete applied as temporary supports such as cemented paste backfill barricades.

• Geomechanics and Engineering
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• v.22 no.2
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• pp.133-142
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• 2020

The evolution of the mining-induced fracture network formed during longwall top coal caving (LTCC) has a great influence on the gas drainage, roof control, top coal recovery ratio and engineering safety of aquifers. To reveal the evolution of the mining-induced stress and fracture network formed during LTCC, the fracture network in front of the working face was observed by borehole video experiments. A discrete element model was established by the universal discrete element code (UDEC) to explore the local stress distribution. The regression relationship between the fractal dimension of the fracture network and mining stress was established. The results revealed the following: (1) The mining disturbance had the most severe impact on the borehole depth range between approximately 10 m and 25 m. (2) The distribution of fractures was related to the lithology and its integrity. The coal seam was mainly microfractures, which formed a complex fracture network. The hard rock stratum was mainly included longitudinal cracks and separated fissures. (3) Through a numerical simulation, the stress distribution in front of the mining face and the development of the fracturing of the overlying rock were obtained. There was a quadratic relationship between the fractal dimension of the fractures and the mining stress. The results obtained herein will provide a reference for engineering projects under similar geological conditions.