• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.229-239
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• 2013

Elastic modulus in rockmass is an important factor to represent the characteristic of rock deformation and is frequently used to estimate the displacement induced due to tunnel excavation or other activities in rockmass. Nevertheless, the study to estimate the elastic modulus, which considers the rock type and joint characteristics (joint shear strength and joint inclination angle), has been done in less frequency. Accordingly, this study is aimed at estimating of elastic modulus in jointed rockmass. For this purpose, numerical parametric studies have been carried out with a consideration of rock and joint conditions. Tunnel displacement results have been used to estimate the elastic modulus of jointed rockmass using the elastic theory of circular tunnel. From this study, the results would be expected to have a great practical use for estimating the displacement induced due to tunnel excavation or other activities in jointed rockmass.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2002.10a
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• pp.84-92
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• 2002

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2006.09a
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• pp.25-36
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• 2006

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2003.03a
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• pp.43-50
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• 2003

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.247-267
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• 2005

이암층 역암층 그리고 화산암층과 같은 특수지질 불량구간에서 터널과 암반사면의 합리적인 시공을 달성하기 위해서는 먼저 대상지질에 대한 지질조건과 암반특성을 정확히 이해하는 것이 필요하며, 이를 바탕으로 지반특성에 적합한 보강대책을 수립하도록 하여야 한다. 본 고에서는 포항지역과 경주지역에서의 미고결 이암 및 역암층 그리고 제주도 화산암층에서의 암반 구조물에 대한 설계 및 시공사례를 검토하고 전형적인 미고결 지층으로 알려진 신생대 지층에서의 터널과 암반과 같은 암반구조물에 대한 설계 및 시공상의 제반 문제점을 고찰하므로서 이에 대한 합리적인 대책을 수립하고자 하였다.

• Journal of the Korean Geotechnical Society
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• v.16 no.5
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• pp.129-140
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• 2000

최근들어 핵폐기물 지하처분장을 중심으로 터널굴착에 의한 주변 암반의 손상상태와 암반특성의 변화를 정량적으로 평가하기 위한 시도가 이루어지고 있다. 이는 암반의 지지력을 적극적으로 이용하는 NATM개념에 의해 터널을 시공할 셩우 안정성 해석과 최적 보강설계를 위해 필수적인 사항으로 고려된다. 그러나 현재까지 암반 손상영역을 평가하기 위해 제시된 여러 방법들은 아직까지 그 적용성과 타당성이 충분히 검증되지 못한 실정이다. 이 연구에서는 코어시추, 실험실시험, 발파진동측정, 보어홀 카메라 등의 여러 방법에 의해 손상영역을 정량적으로 평가하고자 하였으며 가 방법의 적용성을 검토하였다. 암반상태 및 발파조건을 달리하여 시험발파를 수행하였으며 발파 후에 터널벽면에 수직하게 시추를 하여 암석코어를 채취한 뒤 손상정도에 따른 암석의 물리적, 역학적 특성들？ 변화를 정량적으로 나타내고자 하였다. 코어 채취후 시축공에 보어홀 카메라를 사용하여 손상영역을 시각적으로 판별하고자 하였으며 발파진동 측정결과로부터 손상영역을 예측하고 채취한 암석시표에 대한 실험실시험 결과와 비교하여 적용성을 검토하였다.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2001.03a
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• pp.177-187
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• 2001

암반사면의 안정성은 암반 내에 발달한 불연속면의 방향성과 파괴특성에 지대한 영향을 받는다. 두 조의 연속성이 좋은 절리가 발달한 암반의 거동을 해석하기 위해 FLAC의 FISH 언어로 작성된 편재 절리모델을 사용하여 절리암반사면의 안정성을 평가하였다. 해석 결과는 절리의 간격과 방향성을 달리하면서 수행된 UDEC 해석과 저면 마찰 모델 시험결과와 비교하였다. UDEC 해석과 저면 마찰 모형시험 의해 발생된 파괴면의 형상은 유사하였으며, 이 결과로부터 편재절리모델에 의한 FLAC 해석에서의 파괴면은 두 조의 교차하는 절리를 따라 계단식으로 파괴면이 발생함을 추정할 수 있었다.

• The Journal of Engineering Geology
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• v.11 no.1
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• pp.13-23
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• 2001

Rock slope near the road or railroad is affected by the outside temperature and iterative freezing-thawing process during winter and early spring. The purpose of this study is to analyze the stability of rock slope which is iniluenced by deterioration due to the freezing-thawing. Method of analysis is homogenization method which find the strength property of discontinuous rock mass and as a strength failure criterion, Drucker-Prager failure criterion is used, The deterioration property of real rock is obtained by a freezing-thawing labordtory test of tuff and this quantitative property is used as a basic data of stability analysis of rock mass. To evaluate the deterioration depth due to the freezing-thawing in the field rock slope, one dimensional heat conductivity equation is used and as a a result we can find the depth of which is affected by a temperature. After determined the freezing-thawing depth of model slope, the pattern of rock mass strength value of model rock slope which excess the limit of self-load is analyzed.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.1-12
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• 1996

To design the safe and rational rock slope, several rock slopes of roads in Kang-won area were analyzed, and the following results were obtained ; 1. The results were analyzed by stereographic projection at the rock slope that the joint was developed. All of the sloped which were designed by standard slope of rock was not considered that the joints were unstable. 2. The relation of rainfall and slope failure, as well as the danger of failure, was very high when the maximum hourly rainfall was larger than 20mm and when there was a 2-day cumulative rainfall that was larger than 200mm. 3. In the design of rock slope, operated by the stereographic projection considering discontinuity. If turn out unstable, it should be analyzed carefully using the limit equilibrium method. 4. In the design of rock slope, it is desirable to consider the discontinuity of rock(joint, bedding, fault).

• Tunnel and Underground Space
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• v.11 no.2
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• pp.182-189
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• 2001

Rockmass properties have great influence on blasting performance so that it cannot be overemphasized to analyze rockmass properties and to perform blast design based on them. Up to the present, however blast design is performed either considering only uniaxial compressive strength of intact rock or using RMR classification as a blast ability classification scheme. In this paper Ashby's approach is adopted to evaluate blast index. In addition. rockmass classification for the blast design based on joint survey results and pattern design procedure are added to Ashby's original approach. With this extended approach, blastability can be classified considering joint properties and objectiveness of evaluated blast index can be confirmed. This approach is anticipated to enhance the tunnel blast design by considering joint properties and classifying the rockmass for blast design.