• 대한토목학회논문집
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• 제36권1호
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• pp.85-96
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• 2016

본 연구에서는 채움모듈 형태에 따른 준설토의 퇴적분포와 튜브 형상 그리고 토목섬유 튜브의 수침조건에 따른 튜브 내 준설토의 콘 관입 저항특성을 규명하고자 일련의 시험을 수행하였다. 채움모듈 형태에 따른 아크릴 토조와 비닐 튜브 준설토의 퇴적분포를 관찰한 결과 I형 채움모듈은 분화구형상을 나타내고 역T형 채움모듈은 수평방향으로 균등하게 준설토가 퇴적되는 것으로 나타났다. 새만금 내부로부터 채취한 준설토의 채움 단계 별 튜브의 변형은 튜브로부터 배수가 종료됨과 거의 동시에 튜브의 변형이 수렴되고, 토목섬유 튜브 내 준설토의 콘 저항치는 배수의 경우가 수침 보다 2~6배정도 크게 나타났다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.175-178
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• 2003

There is a case to use dredged-sea sand as a filling material because of difficulty of obtaining required filling material for tideland reclamation project from the land. At this time, side slope erosion is occurred because the precipitation falling to the top of bank acts as infiltration water when it pass through inside of the semi-permeable filling section. This study has confirmed the declining effect of permeability by conducting permeability test to the condition of mixing of bentonite to the dredged sea-sand. And also this study has confirmed that the above processed-soil could be used as a water-proof layer to protect infiltration of water through the infiltration flow analysis.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.307-312
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• 1999

The purpose of this study is to ascertain the strength properties of water-permeable concrete with redispersible polymer powder, silica fume and polypropylene fibers. The water-permeable concrete using rediapersibel polymer powder with a water-cement ratio of 25%, polymer-cement ratios of 0 to 10%, silica fume contents of 0 to 10% and fiber contents of 0 to 1.5% are prepared, and tested for flexural strength, compressive strength and water permeability. From the test results, improvements in the strength properties of the water-permeable concrete due to the addition of the redispersible polymer powder, silica fume and fibers are discussed. It is concluded from the test results that the superior flexural and compressive strengths of water-permeable concretes are obtained at a propylene fiber content of 1.0% with a void filling ratio of 50%. And, the water-permeable concrete having a flexural strength of 15.6~28.4kgf/$\textrm{cm}^2$, a compressive strength of 63.5~120.6kgf/$\textrm{cm}^2$, and a coefficient of permeability of 1.14~1.70cm/s at a void filling ratio of 30% can be prepared. Also water-permeable concrete having a flexural strength of 35.6~57.9kgf/$\textrm{cm}^2$, a compressive strength of 164.0~290.0kgf/$\textrm{cm}^2$, and a coefficient of permeability of 0.19~1.04cm/s at a void filling ratio of 50% can be prepared in the consideration of the mix proprotioning factors.

• 터널과지하공간
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• 제16권5호
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• pp.368-376
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• 2006

셰일층으로 구성된 암반사면에서 층리면을 따라 대규모 평면파괴가 사면 중앙부에서 발생하였다. 현장조사시 파괴사면 주변은 지하수 누수 흔적과 점토층의 충전물이 존재하였으며, 파괴원인을 검토한 결과 층리면을 따라 형성된 점토 충전물의 낮은 전단강도와 강우시 인장균열내 형성된 수압에 의해 붕괴가 발생한 것으로 나타났다. 그리고 충전된 절리면의 전단강도 특성을 규명하기 위해서 모래, 점토의 인위적인 충전물을 이용하여 충전재 두께비에 따른 전단강도 특성을 고찰하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 추계 학술발표회
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• pp.256-267
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• 2006

After heavy rainfall, It was occurred massive plane failure along bedding plane of shale in the center of rock slope. It was observed filling material and trace of underground water leakage around of the slope. We tried to find the cause for slope failure, and the result of examination showed that primary factors of the failure were low shear strength of clay filling material and water pressure farmed within tension crack existed in the top of the slope. In this research, in order to examine the features of shear strength of filled rock joint, shear test of filled rock joint was conducted using of artificial filling material such as sand and clay. Also we made an investigation into the characteristics of shear strength with different thickness of filling materials.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권9호
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• pp.4145-4164
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• 2016

Energy harvesting is an increasingly attractive source of power for cellular networks, and can be a promising solution for green networks. In this paper, we consider a cellular network with power beacons powering multiple mobile terminals with microwave power transfer in energy beamforming. In this network, the power beacons are powered by grid and renewable energy jointly. We adopt a dual-level control architecture, in which controllers collect information for a core controller, and the core controller has a real-time global view of the network. By implementing the water filling optimized power allocation strategy, the core controller optimizes the energy allocation among mobile terminals within the same cluster. In the proposed green energy cooperation paradigm, power beacons dynamically share their renewable energy by locally injecting/drawing renewable energy into/from other power beacons via the core controller. Then, we propose a new water filling optimized green energy cooperation management strategy, which jointly exploits water filling optimized power allocation strategy and green energy cooperation in cellular networks. Finally, we validate our works by simulations and show that the proposed water filling optimized green energy cooperation management strategy can achieve about 10% gains of MT's average rate and about 20% reduction of on-grid energy consumption.

• Structural Engineering and Mechanics
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• 제81권2호
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• pp.243-258
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• 2022

In this paper, tensile behavior of joint filling has been investigated under experimental test and numerical simulation (particle flow code). Two concrete slabs containing semi cylinder hole were prepared. These slabs were attached to each other by glue and one cubic specimen with dimension of 19 cm×15 cm×6 cm was prepared. This sample placed in the universal testing machine where the direct tensile stress can be applied to this specimen by implementing a special type of load transferring device which converts the applied compressive load to that of the tensile during the test. In the present work, two different joint filling thickness i.e., 3 mm and 6 mm were prepared and tested in the laboratory to measure their direct tensile strengths. Concurrent with experimental test, numerical simulation was performed to investigate the effect of hole diameter, length of edge notch, filling thickness and filling length on the tensile behavior of joint filling. Model dimension was 19 cm×15 cm. hole diameter was change in four different values of 2.5 cm, 5 cm, 7.5 cm and 10 cm. glue lengths were different based on the hole diameter, i.e., 12.5 cm for hole diameter of 2.5 cm, 10 cm for hole diameter of 5 cm, 7.5 cm for hole diameter of 7.5 cm and 5 cm for hole diameter of 10 cm. length of edge notch were changed in three different value i.e., 10%, 30% and 50% of glue length. Filling thickness were changed in three different value of 3 mm, 6 mm and 9 mm. Tensile strengths of glue and concrete were 2.37 MPa and 6.4 MPa, respectively. The load was applied at a constant rate of 1 kg/s. Results shows that hole diameter, length of edge notch, filling thickness and filling length have important effect on the tensile behavior of joint filling. In fixed glue thinks and fixed joint length, the tensile strength was decreased by increasing the hole diameter. Comparing the results showed that the strength, failure mechanism and fracture patterns obtained numerically and experimentally were similar for both cases.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.101-106
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• 1996

In this study, filling performance of concrete is investigated experimentally for the developmenmt of the concrete to be used in concrete filled steel tubular columns with inner diaphrams. Water-cement ratio with 3 levels, unit water contents with 5 levels, unit coarse aggregate contents with 5 levels, and slump flow with 3 levels are selected for test variables. For the estimation of the filling properties of the concrete, slump flow, V-type funnel time, U-type box height are measured and compared. A device which simulates the steel tubular column is designed and three kinds of concrete are tested with it. As the results, the filling performance is decreased with increasing coarse aggregate content. And, within the scope of this study, concretes with coarse aggregate content less than 880 kg/$\textrm{m}^3$ show good filling performance. To prevent excessive settlement of the concrete pumped into the steel tubular column, slump flow should be controlled within the limited range.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.223-226
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• 1999

The purpose of this study is no examine the combination effect on strength preperties of water-permeable concretes mixed with redispersible polymer, silica fume and polypropylene fibers for overlay in pavement. The water-permeable concrete with a water-cement ration of 25%, polymer-cement ratios of 0 to 10%, silica fume contents of 0 to 10% and polypropylene fiver contents of 0 to 1.5% are prepared, and tested for flexural strength, compressive strength and water permeability. It is concluded concretes are obtained at a polypropylene fiber content of 1.0% and a silica fume content of 10% with a void filling ratio of 50%. And the water-permeable concretes with a flexural strength of 14.1~28.0kgf/$\textrm{cm}^2$, a compressive strength of 71.2~128.0kgf/$\textrm{cm}^2$, and a coefficient of permeability of 1.22~2.52cm/s at a void filling ratio of 30% can be prepared. Also water-permeable concretes having flexural strength of 24.9~57.9kgf/$\textrm{cm}^2$, a compressive strength of 83.8~268.5kgf/$\textrm{cm}^2$, and a coefficient of permeability of 0.24~1.04cm/s at a void filling ratio of 50% can be prepared in the consideration of the mix proportioning factors.

• Geomechanics and Engineering
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• 제13권6호
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• pp.1011-1025
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• 2017

The geological conditions surrounding the Jijiapo Tunnel of the Three Gorges Fanba Highway project in Hubei Province are very complex. In this paper, a 3-D physical model was carried out to study the evolution process of filling-type fracture water inrush and mud gush based on the conditions of the section located between 16.040 km and 16.042 km of the Jijiapo Tunnel. The 3-D physical model was conducted to clarify the effect of the self-weight of the groundwater level and tunnel excavation during water inrush and mud gush. The results of the displacement, stress and seepage pressure of fracture and surrounding rock in the physical model were analyzed. In the physical model the results of the model test show that the rock displacement suddenly jumped after sustainable growth, rock stress and rock seepage suddenly decreased after continuous growth before water inrushing. Once water inrush occured, internal displacement of filler increased successively from bottom up, stress and seepage pressure of filler droped successively from bottom up, which presented as water inrush and mud gush of filling-type fracture was a evolving process from bottom up. The numerical study was compared with the model test to demonstrate the effectiveness and accuracy of the results of the model test.