• 한국지반공학회지:지반
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• 제12권3호
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• pp.83-98
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• 1996

이 논문에서는 역순법 원리를 이용한 역해석 결과를 제시하였다. 국내에서 건설된 두 곳의 지하비축기지 공사 중에 계측한 자료를 이용하여 비축기지 진입터널 주위 암반의 변형계수와 초기 지압을 계산하였다. 역해석에서 얻어진 결과를 입력자를로 하여 유한요소해석을 수행하였으며 그 결과를 계측치와 비교, 검토하였다.

• 터널과지하공간
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• 제3권2호
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• pp.142-151
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• 1993

In this study, the deformation characteristics of atrtificially fractured joints of granite under normal and shear loading were investigated. To obtain the characteristics of joint deformation, compression and shear tests were performed in the laboratory on three different sizes of rock specimens. The rock used in the experimens was Iksan granite. Joints were produced artificially by fracturing using the apparatus for generating extension-joint. Joint normal deformability was studied by conducting cyclic loading tests on the joints. Joint closure varied non-linearly with normal stress through cyclic loadings. As normal stress increased, the joints gradually reached a state of maximum joint closure. The relation between normal stress and joint closure for mated and unmated joints was well described by the hyperbolic and exponential function, respectively. Joint shear deformability was studied by performing direct shear tests under normal stresses on the joints. it was shown that the behaviour in the prepeak range was non-linear and joint shear stiffness depended on the size of specimen and the normal stress.

• 터널과지하공간
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• 제7권2호
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• pp.130-135
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• 1997

When crystalline rocks are heated, thermal stress is induced by the differences in thermal expansion of the mineral composition and its orientation. In this study, high temperature uniaxial compressive tests were carried out for Iksan and Hwangdeung granites to study the deformation and failure behavior due to thermal loading. Compressive and tensile strength of Hwangdeung granite for 20$0^{\circ}C$ decreased to 80% and 82% of the room temperature strength, and those of Iksan granite decreased to 90% and 92% for 20$0^{\circ}C$, respectively. Elastic moduli of both granites were decreased sharply at the stress level of 80% of ultimate failure strength. Elastic moduli of both granites by variation of temperature at 50% of ultimate failure strength was decreased as almost linearly.

• 터널과지하공간
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• 제3권1호
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• pp.40-49
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• 1993

In this study, the indirect estimation method of the support load which is based upon the integrated measuring technique suggested by Kovari was applied to the calculation of support load in the mine roadway. Four test supports were installed in the area where they had to be replaed. Two of those were GI-130 rigid supports and the others were U-26 yieldable supports. The vibrating wire strain gages which were attached inpairs on the steel arch support were used to provide an accurate measurement. Bending moments and normal forces obtained from strain gage pairs were used to calculate the support load. This method was also verified by laboratory bending tests. The results obtained from the back-calculction method showed relatively good agreement with the measured convergence for each crossection.

• 한국지반공학회지:지반
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• 제13권2호
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• pp.169-184
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• 1997

Drucker-Prayer의 항복기준을 이용한 원형터널의 해석을 위하여 간략한 수치해석 기법이 유도되었다. 유도된 이론해를 근거로 컴퓨터 프로그램 FDAXP가 개발되었구 예제 해석을 통하여 프로그램의 신뢰도를 검증하여 만족한 결과를 얻었다. 소개된 프로그램 FDAXP는 깊은 터널과 쉽게 소성변형이 발생되는 지반 및 암반에서의 초기 터널해석에 손쉽게 적용될 수 있으며, 기존의 상용 프로그램들에서 Drunker-Prayer model을 검증하는데에 매우 유용하게 사용되리라 사료된다.

• 터널과지하공간
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• 제4권3호
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• pp.261-273
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• 1994

Direct shear tests were carried out on the rock joints and artificial discontinuities to investigate the influence of joint roughness on the shear strength and deformation behaviour. Single direct shear testing apparatus used in experiment was designed and manufactured. Its capacity is 200 tons of shear load, 20 tons of normal load and 50$\textrm{cm}^2$ of maximum shear area. Test samples were cement mortar with artificial discontinuity and sandstone with natural joint. Peak shear strength was increased as joint roughness or normal stress was increased, especially, linearly increased with roughness angle in cement mortar. If joint roughness angle was constant at low normal stress, shear strength was not affected by width and height of joint roughness in cement mortar. Peak shear strengths obtained from tests were larger than the values calculated by Barton's equation, and shear stiffness was increased with joint roughness coefficient.

• 터널과지하공간
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• 제8권2호
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• pp.96-106
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• 1998

Rock contains discontinuities at all scales. These discontinuities make rock behave in a complex way. This paper discusses a new approach to underground design based on the theory of rock fracture mechanics. The mechanism of deformation and failure of coal was studied by observing the distributions of length, orientation and spacing of the pre-existing as well as stress-induced cracks. Different types of crack information. The crack information is dependent on the scale used. The cracks propagate along the intersections of the pre-existing cracks, and both extensile and shear crack growth occur depending on the direction of the load relative to the bedding planes. An analytical model that takes into account both shear and extensile crack growth was developed to predict the nonlinear stress-strain behavior of coal including strain-hardening and strain-softening.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.172-175
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• 2003

우리나라 서남해 도서지역의 암반대수층을 통한 해수침투 실태 파악과 합리적인 지하수 이용관리 계획을 수립하기 위하여 농림부와 농업기반공사가 운영중인 해수침투 관측망에 대한 대략적인 소개와 일부 지역의 운영 사례를 제시하였다. 강화도 숭뇌지역 운영사례에서는 2002년 1월 1일부터 11월 30일까지의 수위, 전기전도도, 수온 등 세 항목의 지하수 장기관측 결과와 전기전도도 검층, 변형된 단극배열 전기비저항 탐사 및 지하수 시료들의 이온분석 결과를 바탕으로 관측정의 해수유입 실태를 파악하였으며, 소유역에 대한 개략적인 해수침투 유형파악이 가능함을 확인하였다.

• 화약ㆍ발파
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• 제38권3호
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• pp.30-43
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• 2020

암석동역학은 동적하중조건하에서의 암반이나 암석의 역학적 거동에 대해 연구하는 학문으로, 자원개발이나 토목, 지진을 비롯한 재난재해, 국방과학 등 다양한 분야에 걸쳐 그 필요성이 증대되고 있다. 본 보고에서는 암석재료에 대한 동적 실험기법들과 동적 하중상태에서 암석이 보이는 역학적 거동 특성에 대한 최근의 연구결과들을 소개하고자 한다.

• 한국지반공학회논문집
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• 제17권4호
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• pp.93-105
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• 2001

해성토층(풍화토 및 모래질 충적토가 암반 위에 쌓인) 위에 준설매립된 수도권 해안매립지역에서 원형의 대심도 굴착공사로 인하여 발생하는 지중연속벽의 수평변위에 대한 현장계측을 중심으로 연구를 수행하였다. 현장측정으로는 지중연속벽의 8방향에서 벽체수평변위와 철근응력, 토압, 간극수압 등이 측정되었고, 정확한 측정결과를 얻기 위하여 합리적인 해석 및 보정방법이 연구되었다. 현장측정결과 굴착시공단계에 따라서 벽체수평변위가 증가하였으며, 일정깊이에 존재하는 점토층을 굴착함으로써 간극수압의 급격한 변화가 측정되었다. 한편, 굴착전후의 구속압감소에 따른 지반물성치의 변화를 정리하였다. 굴착전후의 탄성계수는 일정깊이까지 상당한 정도로 감소됨을 알 수 있었고 굴착전후 여러 가지 시험방법에 따른 탄성계수의 차이들을 비교하였다.