• 동굴
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• 제8호
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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.

• 동굴
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• 제4호
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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.

• 동굴
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• 제90호
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• pp.27-33
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• 2009

천연동굴의 스포츠관광자원으로의 활용방안에 대하여 모색하였다. 천연동굴의 활용에서 심신수양과 스포츠활동의 장소로서의 가치는 충분히 논의된 바가 있다. 이에 우리나라 전역에 분포하는 다양한 천연동굴의 발굴과 환경보전을 전제로 한 스포츠관광자원으로서의 활용이 기대된다.

• Steel and Composite Structures
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• 제48권1호
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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.

• 터널과지하공간
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• 제14권5호
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• pp.305-317
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• 2004

세계적으로 장벽식 채탄법이 많이 적용된 반면, 국내에서는 좁고 경사진 탄층의 특성에 의하여 위경사승 붕락식 또는 중단 붕락식 채탄법이 주로 사용되었다. 이러한 이유로 국내에 산재하는 폐광산은 그 규모와 특성을 파악하기가 어려운 특징이 있다. 따라서, 본 고에서는 국내 채탄법의 특정을 파악한 후 이를 바탕으로 동해고속도로 2공구 현장의 폐광산에 대한 조사 및 안정성 평가를 실시하였으며 추후 당 현장에 적용 가능한 최적의 지반보강공법을 선정하였다.

• 동굴
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• 제4호
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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.

• 동굴
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• 제10권
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• pp.61-70
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• 1999

• Geomechanics and Engineering
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• 제19권3호
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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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• 제9권2호
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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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• 제22권2호
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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.