• Journal of Korean Tunnelling and Underground Space Association
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• v.6 no.1
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• pp.41-50
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• 2004

The numerical investigation for the effects of blasting-induced vibration on adjacent dam and pore water pressure fluctuation was conducted through solid-water coupled analysis under dynamic loading. The stability of dam was examined by peak particle velocity of core. Pore water pressure distributions were calculated by steady state flow analysis using coupled analysis on ground water and blasting-induced vibration. The influence of pore water pressure and the effective stress distribution in the ground were also investigated. Furthermore, effective stress alteration was examined by applying Finn & Byrne Model to monitor the generation and dissipation of pore water pressure.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2003.03a
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• pp.121-134
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• 2003

본 연구대상은 $\bigcirc$$\bigcirc$우회도로 Sta.3＋300~600 구간에 형성된 높이 약 50m의 대절토 암반사면으로 대부분 절취가 완료된 상태에서, 1차로 사면 좌측부의 발파암과 풍화암의 경계부를 따라 인장균열이 소규모로 형성되면서 Slip 등 사면파괴활동이 시작되었으며, 2차로 활동높이 35m, 활동폭 40m, 활동깊이 약 l0m 규모로 붕괴되었고, 주변에도 인장균열의 발생이 확인되는 등 추가 붕괴의 징후가 있어 사면의 안정성을 검토하였다. Rock Cleavages가 발달한 천매암으로 구성된 파괴활동사면을 대상으로 지표지질조사, 추가시추조사, 전기비저항탐사, 시추공 영상촬영(BIPS)을 실시하여 사면붕괴의 원인과 추후에 예상되는 붕괴의 양상을 파악하고, 연구지역에 가장 적합한 보강대책을 수립하고자 하였다.

• Explosives and Blasting
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• v.23 no.3
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• pp.57-74
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• 2005

In the past, explosives like dynamite was used to blast rock. However, today it is difficult to use explosives in urban blastinglike excavation for subway, building, and housing land. According to Korea Department of Construction and Transportation's proposal for blasting design manual and test blasting, from TYPE I blasting to TYPE IV blasting are recommended when we determine 0.3cm/sec(centisec) as a maximum allowable ground vibration with a distance between $25m\~120m$ from structures. This article was written to introduce one of TYPE I (reck blasting within 25m from structures) blasting method, Nano-Plasma blasting method. When Nano-Plasma blasting method is applied in urban blasting job, ground vibration (15m away from blasting point) is expected 0.1cm/sec, which is only half of a ground vibration when low ground vibration blasting method is applied. By this unique characteristic, Nano-Plasma blasting method is epochal urban blasting technique.

• Journal of the Korean Geophysical Society
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• v.5 no.2
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• pp.153-161
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• 2002

In order t determine blasting sites for the crustal refraction studies in the korean peninsula, seismic refraction profiling was conducted at two sites in the reclaimed land of Seosan. At a quarry for construction material and another site on a rice field 2km east of the quarry, 24 channel refraction profiling of 46m was conducted at a geophone spacing of 2m. Seismic velocity profiles obtained through tomographic invesion reveal that the quarry is regarded as an ideal place for blasting based on the observation that fresh basements with seismic velocities of 3,900 m/s or greater locate approximately 6m deep. On the contrary, under the reclaimed rice field, the basements are weathered more, of slower velocities, and buried deeper than quarry, indicating not an ideal location for detonating seismic explosives of large amounts.

• Tunnel and Underground Space
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• v.8 no.3
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• pp.171-177
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• 1998

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2004.10a
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• pp.73-81
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• 2004

• Journal of the Korean Geosynthetics Society
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• v.16 no.1
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• pp.9-17
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• 2017

In this study, the field density test was conducted as a volume conversion factor for the design of the excavation soil of the blasting rock. As a result of the field density test, the average volume conversion factor of rock was 1.001, which was smaller than the volume conversion factor of weathered rock 1.1. In the case of rock filled soil, the causes of the increase and decrease of the volume of the soil are provided by various phenomena. However, the specific techniques such as investigation and test methods are insufficient. Therefore, it was confirmed that the method of field density test is very useful method.

• Explosives and Blasting
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• v.30 no.2
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• pp.29-42
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• 2012

Variables influencing the free face movement due to rock blasting include the physical and mechanical properties, in particular the discontinuity characteristics, explosive type, charge weight, burden, blast-hole spacing, delay time between blast-holes or rows, stemming conditions. These variables also affects the blast vibration, air blast and size of fragmentation. For the design of surface blasting, the priority is given to the safety of nearby buildings. Therefore, blast vibration has to be controlled by analyzing the free face movement at the surface blasting sites and also blasting operation needs to be optimized to improve the fragmentation size. High-speed digital image analysis enables the analyses of the initial movement of free face of rock, stemming optimality, fragment trajectory, face movement direction and velocity as well as the optimal detonator initiation system. Even though The high-speed image analysis technique has been widely used in foreign countries, its applications can hardly be found in Korea. This thesis aims at carrying out a fundamental study for optimizing the blast design and evaluation using the high-speed digital image analysis. A series of experimentation were performed at two large surface blasting sites with the rock type of shale and granite, respectively. Emulsion and ANFO were the explosives used for the study. Based on the digital images analysis, displacement and velocity of the free face were scrutinized along with the analysis fragment size distribution. In addition, AUTODYN, 2-D FEM model, was applied to simulate detonation pressure, detonation velocity, response time for the initiation of the free face movement and face movement shape. The result show that regardless of the rock type, due to the displacement and the movement velocity have the maximum near the center of charged section the free face becomes curved like a bow. Compared with ANFO, the cases with Emulsion result in larger detonation pressure and velocity and faster reaction for the displacement initiation.

• Explosives and Blasting
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• v.28 no.1
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• pp.40-54
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• 2010

The messer shield method applys mainly to a tunnel with small cross-section of a weathered soil or weathered rock district and is fulfilled mostly by man-power excavation. but in case that hard rock exposes on tunnel face, incredible is an application of the rock-splitting method using a hydraulic power or a blasting method. This study represents the case of a blasting method which can control to be practiced by the minimum charges of 125 g an initial vibration occurring at the cut instead of the rock-splitting method, even though water pipe and gas pipe are closely adjacent.

• Proceedings of the KSEE Conference
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• 2006.10a
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• pp.167-184
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• 2006

There is cattle shed and house structure of a country village in the vicinity of the construction site. that is why the environmental effect evaluation on blasting had been done in advance to prevent any harm to those from the work. As the result, it is impossible to apply to the blasting method, and the Super wedge method, a kind of a rock-splitting method which there is no secondary breaking by a breaker of the methods breaking &excavating rock according to the classification of the blasting method by the ministry of construction & transpotation, applied to decrease noise and vibration, and to the work classification, the extent of noise and vibration measured with the instrument only for noise(SC-310c) and with the instrument only for vibration(BLASTMATE) respectively. A drilling, splitting, collecting, loading works at the closest point(about 10m) is barely possible on the consideration of vibration to the result of measurement, but carefulness needs on moving of equipment. On the case of noise, even drilling, collecting, loading work except splitting at the comparatively close point(about 20m) is difficult. So, the method breaking &excavating rock according to the classification of the blasting method by the ministry of construction & transpotation has to apply in consideration of noise level in accordance with the work processing.