• Title/Summary/Keyword: large-scale test

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Seismic Performance Evaluation of Shear-Flexure RC Piers through Comparative test of Real Scale and Reduced Scale Model (실물 및 축소모형 비교실험을 통한 휨-전단 RC교각의 내진성능평가)

  • 곽임종;조창백;조정래;김영진;김병석
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.849-854
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    • 2002
  • From the analysis results of some as-built drawings in national roadway bridges in Korea, many bridge piers are expected to show complex shear-flexural behaviour under earthquakes. But the previous research works about the seismic evaluation of bridges considered flexural behaviour RC piers only. In addition, the past bridge design specifications in Korea didn't include limitation on the amount of longitudinal lap splices in the plastic hinge zone of piers. Thus a large majority of non-seismically designed bridge piers in Korea may have lap splices in plastic hinge zone. In this study, prototype pier was selected among existent bridge piers whose failure mode is expected to be complex shear-flexural mode. And then, full scale and 1/2 reduced scale model RC piers with various longitudinal lap splice details were constructed. From the quasi static test results on these model RC piers, the effect of longitudinal lap splices on the seismic performance of bridges piers was analyzed. And the seismic capacity of the non-seismically designed shear-flexural RC piers was evaluated.

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SAMPLING BASED UNCERTAINTY ANALYSIS OF 10 % HOT LEG BREAK LOCA IN LARGE SCALE TEST FACILITY

  • Sengupta, Samiran;Dubey, S.K.;Rao, R.S.;Gupta, S.K.;Raina, V.K
    • Nuclear Engineering and Technology
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    • v.42 no.6
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    • pp.690-703
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    • 2010
  • Sampling based uncertainty analysis was carried out to quantify uncertainty in predictions of best estimate code RELAP5/MOD3.2 for a thermal hydraulic test (10% hot leg break LOCA) performed in the Large Scale Test Facility (LSTF) as a part of an IAEA coordinated research project. The nodalisation of the test facility was qualified for both steady state and transient level by systematically applying the procedures led by uncertainty methodology based on accuracy extrapolation (UMAE); uncertainty analysis was carried out using the Latin hypercube sampling (LHS) method to evaluate uncertainty for ten input parameters. Sixteen output parameters were selected for uncertainty evaluation and uncertainty band between $5^{th}$ and $95^{th}$ percentile of the output parameters were evaluated. It was observed that the uncertainty band for the primary pressure during two phase blowdown is larger than that of the remaining period. Similarly, a larger uncertainty band is observed relating to accumulator injection flow during reflood phase. Importance analysis was also carried out and standard rank regression coefficients were computed to quantify the effect of each individual input parameter on output parameters. It was observed that the break discharge coefficient is the most important uncertain parameter relating to the prediction of all the primary side parameters and that the steam generator (SG) relief pressure setting is the most important parameter in predicting the SG secondary pressure.

Behavior Characteristics of Precast Concrete-Panel Retaining Wall Adhered to In-situ Ground through Large Scaled Load Test (대형재하시험을 통한 원지반 부착식 패널옹벽의 거동특성)

  • Shin, Yuncheol;Min, Kyongnam;Kim, Jinhee;Ahn, Taebong
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.11
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    • pp.45-53
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    • 2016
  • A precast panel wall system resists against the horizontal earth pressure by increasing the shear strength of ground by reinforcement connected to the panel. The application of precast panel wall system is growing to lately minimize the earth work and environmental damage caused by large cut slope and to use the limited land effectively. The ground adhered panel wall system is the construction method that has the panel engraved with natural rock shape to improve the landscape. This system is developed to complete Top-Down method, and it is possible to have vertical cut, and to adhere to in-situ ground, improve construction ability by minimizing the ground relaxation and exclusion the trench and backfill process. In this study the field tests were performed to verify the construction ability about the vertical cut and complete Top-Down process and the construction behavior of ground adhered panel wall system was analyzed by large scale loading test and measurement results during loading test.

Analysis on Shear characteristics of Rubble Stone Using Large-Scale Triaxial Test (대형삼축압축시험을 이용한 사석의 전단 특성 분석)

  • Jung, Chul-Min;Kim, Jong-Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.6 no.2
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    • pp.263-275
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    • 2002
  • In general, the values of shear strength properties of rubble stones have been given quoting from Japanese empirical recommendation when breakwater and offshore structures of port and harbor facilities were designed in Korea. but by large-scale triaxial test(specimen diameter 30cm, specimen height 60cm) carried out in Korean Water Resources Corporation in 2001, for the first time in korea, shear strength properties of rubble stones are evaluated directly. These are compared with the Japanese empirical recommendation. Therefore, the value of shear strength properties of rubble stones have been usually given quoting from Japanese empirical recommendation without laboratory or in-situ tests, but the results of this study state that shear strength properties of rubble stone can be rationally determined and shear behavior characteristics of rubble stone can be invesgated by large-scale triaxial test

Dynamic Active Earth Pressure of Gabion-Geotextile Bag Retaining Wall System Using Large Scale Shaking Table Test (진동대 실험을 이용한 게비온-식생토낭 옹벽 시스템의 동적주동토압 산정)

  • Kim, Da Been;Shin, Eun Chul;Park, Jeong Jun
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.12
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    • pp.15-26
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    • 2019
  • This study was conducted to characterize shearing strength of geotextile bag, connecting materials and gabion. A largescale shaking take tests were conducted to assess kinetic characteristics of gabion-geotextile bag retaining wall. Based on the results of large-scale shaking table test, dynamic characteristics of gabion-geotextile bag retaining wall structure against acceleration, displacement, and earth pressure were also analyzed. The increments of dynamic active earth pressure were determined to be (0.376-0.377)H at 1:0.3 slope and $(0.154-0.44)g_n$ earthquake acceleration, and (0.389-0.393)H at 1:1 slope, suggesting that the increments tend to rise as the slope decreases.

Implementation of Network Level Simulator for Tactical Network Performance Analysis (전술통신망 성능분석을 위한 네트워크 시뮬레이터 구현)

  • Choi, Jeong-In;Shin, Sang-Heon;Baek, Hae-Hyeon;Park, Min-Ho
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.5
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    • pp.666-674
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    • 2013
  • This paper studied about the design and implementation of tactical communication network simulator in order to obtain tactical communication network parameter, such as link capacity and routing plan, and a number of exceptional cases that may occur during actual deployment by conducting simulation of a large-scale tactical communication networks. This tactical communication network simulator provides equipment models and link models of commercial OPNET simulator for tactical communication network. In addition, 6 types of simulation scenario writings convenience functions and traffic generation models that may occur in situations of tactical communication network environment were implemented in order to enhance user friendliness. By taking advantages of SITL(System-In-The-Loop) function of OPNET, the tactical communication network simulator allows users to perform interoperability test between M&S models and actual equipment in operating simulation of tactical communication network, which is run on software. In order to confirm the functions and performance of the simulator, small-scale of tactical communication network was configured to make sure interoperability between SITL-based equipment and a large-scale tactical communication network was simulated and checked how to cope with traffic generated for each network node. As the results, we were able to confirm that the simulator is operated properly.

Strength Parameters and Shear Behaviors of North-Cheju Basalt Rubble Using Large-scale Triaxial Test (대형삼축압축시험을 이용한 북제주현무암 사석재의 강도정수 및 전단거동)

  • 정철민;김종수;채영수
    • Journal of the Korean Geotechnical Society
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    • v.18 no.2
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    • pp.147-160
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    • 2002
  • According to the Korean Design Code for port and harbor facilities, bearing capacity of rubble mound under eccentric and inclined load is calculated by the simplified Bishop method, and strength parameters are recommended to be c=0.2kg/$cm^2$ and \phi=35^P\circ}$ fur standard rubble if the compressive strength of parent rock is greater than 300kg/$cm^2$, according to research results by Junichi Mizukami(1991). But this facts have never been verified in Korea because there was no large-scale triaxial test apparatus until 2000 in Korea. For the first time in Korea, the large-scale triaxial test(sample diameter 30cm ; height 60cm) on the rubble originated from porous basalt rock in North-Cheju was accomplished. Then strength parameters for basalt rubble produced in North-Cheju are recommended to be c:0.3kg/$cm^2\; and \phi=36^{\circ}$ if the compressive strength of parent rock is greater than 400kg/$cm^2$. And the shear behavior characteristics of rubble, represented as particle breakage and dilatancy, are investigated.

Large-Scale Current Source Development in Nuclear Power Plant (원전에 사용되는 직류전압제어 대전류원의 개발)

  • Jong-ho Kim;Gyu-shik Che
    • Journal of Advanced Navigation Technology
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    • v.28 no.3
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    • pp.348-355
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    • 2024
  • A current source capable of stably supplying current as a measurement medium is required in order to measure and test important facilities that require large-scale measurement current, such as a control element drive mechanism control system(CEDMCS), in case of dismantling a nuclear power plant. However, it can provides only voltage power as a source, not current, although direct voltage controlled constant current source is essential to test major equipment. That kind of source is not available to supply stable constant current regardless of load variation. It is just voltage supplier. Developing current source is not easy other than voltage source. Very large-scale current source up to ampere class more than such ten times of normal current is inevitable to test above mentioned equipment. So, we developed large-scale current source which is controlled by input DC voltage and supplies constant stable current to object equipment according to this requirement. We measured and tested nuclear power plant equipment using given real site data for a long time and afforded long period load test, and then proved its validity and verification. The developed invetion will be used future installed important equipment measuring and testing.