• 제목/요약/키워드: Full scale

검색결과 3,022건 처리시간 0.035초

Model-Ship Correlation Study on the Powering Performance for a Large Container Carrier

  • Hwangbo, S.M.;Go, S.C.
    • Journal of Ship and Ocean Technology
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    • 제5권4호
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    • pp.44-50
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    • 2001
  • Large container carriers are suffering from lack of knowledge on reliable correlation allowances between model tests and full-scale trials, especially at fully loaded condition, Careful full-scale sea trial with a full loading of containers both in holds and on decks was carried out to clarify it. Model test results were analyzed by different methods but with the same measuring data to figure out appropriated correlations factors for each analysis methods, Even if it is no doubt that model test technique is one of the most reliable tool to predict full scale powering performance, its assumptions and simplifications which have been applied on the course of data manipulation and analysis need a feedback from sea trial data for a fine tuning, so called correlation factor. It can be stated that the best correlation allowances at fully loaded condition for both 2-dimensional and 3-dimensional analysis methods are fecund through the careful sea trial results and relevant study on the large size container carriers.

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Experimental and analytical behaviour of composite slabs

  • Lopes, Emanuel;Simoes, Rui
    • Steel and Composite Structures
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    • 제8권5호
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    • pp.361-388
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    • 2008
  • The Eurocode 4 presents some negative aspects in the design of composite slabs by the m-k Method or the Partial Connection Method. On one hand, the component chemical adherence is not accounted for in the connection between the profiled steel sheet and the concrete. On the other hand, the application of these methods requires some fitting parameters that must be determined by full scale tests. In this paper, the Eurocode 4 methods are compared with a method developed at the Federal Polytechnic School of Lausanne, based on pullout tests, which can be a valid alternative. Hence, in order to calculate the necessary parameters for the three methods, several tests have been performed such as the full scale test described in Eurocode 4 and pull-out tests. This last type of tests is of small dimensions and implicates lower costs. Finally, a full-scale test of a steel-concrete composite slab with a generic loading is presented, with the goal of verifying the analytical formulation.

Experiment and simulation analysis on full scale double-layer concrete shell

  • Thanh Quang Khai Lam;Thi My Dung Do
    • Computers and Concrete
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    • 제31권1호
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    • pp.9-21
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    • 2023
  • The published studies usually used analytical method, numerical methods or experimental method to determine the stress-strain state and displacement of the single-layer or multi-layer curved shell types, but with a small scale model. However, a full scale multi-layer doubly curved concrete shell roof model should be researched. This paper presents the results of the experiment and simulation analysis involving stress-strain state, sliding between layers, the formation and development of the full scale double-layer doubly curved concrete shell roof when this shell begins to crack. The results of the this study have constructed the load-sliding strain relationship; strain diagram; stress diagram in the shell layers; the Nx, Ny membrane force diagram and deflection of shell. Thisresults by experimental method on a full scale model of concrete have clarified the working of multi-layer doubly curved concrete shell roof. The experimental and simulation results are compared with each other and compared with the Sap2000 software.

A numerical study of scale effects on performance of a tractor type podded propeller

  • Choi, Jung-Kyu;Park, Hyoung-Gil;Kim, Hyoung-Tae
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제6권2호
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    • pp.380-391
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    • 2014
  • In this study, the scale effect on the performance of the podded propeller of tractor type is investigated. Turbulent flow computations are carried out for Reynolds numbers increasing progressively from model scale to full scale using the CFD analysis. The result of the flow calculation for model scale Reynolds numbers agrees well with that of the experiment of a large cavitation tunnel. The existing numerical analysis indicates that the performance of the podded propeller blades is mainly influenced by the advance coefficient and relatively little by the Reynolds number. However, the drag of pod housing with propeller in operation is different from that of pod housing without propeller due to the acceleration and swirl of propeller slipstream which is altered by propeller loading as well as the pressure recovery and friction according to Reynolds number, which suggests that the pod housing drag under the condition of propeller in operation is the key factor of the scale effect on the performance between model and full scale podded propellers. The so called 'drag ratio', which is the ratio of pod housing drag to total thrust of podded propeller, increases as the advance coefficient increases due to accelerated flow in the slipstream of the podded propeller. However, the increasing rate of the drag ratio reduces continuously as the Reynolds number increases from model to full scale progressively. The contribution of hydrodynamic forces, which acts on the parts composed of the pod housing with propeller operating in various loading conditions, to the thrust and the torque of the total propeller unit are presented for a range of Reynolds numbers from model to full scales.

축소모델과 실모델 면진베어링의 성능실험에 관한 연구 (A Study on Testing of 1/4-scale and Full-size Seismic Isolation Bearings)

  • 정민기;정지만;김두훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1996년도 춘계학술대회논문집; 부산수산대학교, 10 May 1996
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    • pp.194-202
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    • 1996
  • An approach to increase the seismic resistance of large structures is to reduce the seismic forces, to which structures are subjected by base isolation systems. The anti-seismic performance of base-isolated beatings has been verified experimentally by shaking table tests. However, it may be difficult to perform the tests for the full-scale beatings of base-isolated structures. Therefore, the test program was designed to evaluate the reliability and properties of the beatings under a range of loading conditions including axial stress, loading frequency and direction, and temperature. The effects of scale were also evaluated by comparing the results of the 1/4-scale beatings with those from the full-scale bearings, and the ultimate behavior of both types of bearings with evaluated through a series of roll-out tests. This report draws comparisons among the different tests and bearings to determine the importance of various factors including load history, axial stress, and frequency. Comparisons between the 1/4-scale bearings were difficult because of the scaling effects in manufacturing and thermal radiation, but qualitative results from the 1/4-scale bearings can certainly be extrapolated the full-scale bearings.

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Rudder Torque 및 Force 실선 계측 Method (Full Scale Measurement Method for Rudder Torque & Force)

  • 임정호;박경락;옥유관
    • 대한조선학회 특별논문집
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    • 대한조선학회 2011년도 특별논문집
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    • pp.1-4
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    • 2011
  • The full spade rudder for the high speed has advantage to prevent gap cavitation of the rudder. DSME has developed the full spade rudder and GL has carried out CFD analysis and FE analysis to confirm strength and fatigue for DSME and Owner. Necessarily, it needs to compare rudder torque & rudder force between CFD, FE analysis and full scale measurement. This report introduces the measurement method and application of strain gauge for measuring the rudder torque and rudder force for the 8,400 TEU container ship.

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프리캐스트 패널의 양중에 따른 거동 계측 연구 (Behavior Monitoring of Precast Concrete Panels in Lifting)

  • 양성철;김성민;한승환;윤상천
    • 한국구조물진단유지관리공학회 논문집
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    • 제16권3호
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    • pp.51-59
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    • 2012
  • 본 연구에서는 도로용 패널로 사용되는 프리캐스트 콘크리트 슬래브의 양중, 이동 및 설치 등 제품의 제작 및 시공 시 발생될 수 있는 양중에 따른 안전 설계요소를 분석하였다. 그 결과를 토대로 축소형 슬래브(Full-scale용 슬래브의 1/2 크기 규모로 $1.8m{\times}3m{\times}0.15m$) 2개와 Full-scale용 슬래브($3.9m{\times}5.95m{\times}0.29m$) 1개를 제작하였으며, 콘크리트 및 철근 게이지를 설치하여 슬래브의 양중 및 트럭에 적재하여 이동 시 급작스런 동적거동으로 인해 발생되는 콘크리트 슬래브의 변형률을 측정하였다. 축소형 슬래브의 경우 60도로 양중 시 정지상태의 변형률에 비해 약 3.54배의 변형률에 도달하였다. 그러나 Full-scale용 슬래브는 양중 및 운반 중의 동적 거동을 계측한 결과 동적변형률이 그리 크지는 않아 양중과 운반 시에 파손될 염려는 거의 없는 것으로 판단되어 본 연구에서 채택한 양중 시스템의 안전성을 확인하였다.

Comparison between wind load by wind tunnel test and in-site measurement of long-span spatial structure

  • Liu, Hui;Qu, Wei-Lian;Li, Qiu-Sheng
    • Wind and Structures
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    • 제14권4호
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    • pp.301-319
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    • 2011
  • The full-scale measurements are compared with the wind tunnel test results for the long-span roof latticed spatial structure of Shenzhen Citizen Center. A direct comparison of model testing results to full-scale measurements is always desirable, not only in validating the experimental data and methods but also in providing better understanding of the physics such as Reynolds numbers and scale effects. Since the quantity and location of full-scale measurements points are different from those of the wind tunnel tests taps, the weighted proper orthogonal decomposition technique is applied to the wind pressure data obtained from the wind tunnel tests to generate a time history of wind load vector, then loads acted on all the internal nodes are obtained by interpolation technique. The nodal mean wind pressure coefficients, root-mean-square of wind pressure coefficients and wind pressure power spectrum are also calculated. The time and frequency domain characteristics of full-scale measurements wind load are analyzed based on filtered data-acquisitions. In the analysis, special attention is paid to the distributions of the mean wind pressure coefficients of center part of Shenzhen Citizen Center long-span roof spatial latticed structure. Furthermore, a brief discussion about difference between the wind pressure power spectrum from the wind tunnel experiments and that from the full-scale in-site measurements is compared. The result is important fundament of wind-induced dynamic response of long-span spatial latticed structures.

ISO 9705 - Full-scale Room Test 시험방법을 이용한 샌드위치 패널의 화재 특성 연구 (A Study on the Fire Characteristics of Sandwich Panels by ISO 9705 - Full-scale Room Test)

  • 권오상;유용호;김흥열;이정일
    • 한국화재소방학회논문지
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    • 제23권6호
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    • pp.39-45
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    • 2009
  • 본 연구에서는 샌드위치패널의 종합적인 화재특성을 파악하기 위하여 스티로폼, 난연 스티로폼, 우레탄폼, 난연 우레탄폼, 그라스울 샌드위치패널에 대해 국제 화재 시험 규격인 ISO 9705 시험(Full-scale room test)을 실시하였다. 이를 바탕으로 EN 13501-1 및 Eurefic Research Program에서 제시하고 있는 분류기준에 적용하여 샌드위치패널의 종합적인 화재특성을 분석하였다. 그 결과 그라스울 샌드위치 패널은 A class, 난연 우레탄폼과 난연 스티로폼 샌드위치 패널은 B class로 나타났다. 플래시오버가 발생한 스티로폼, 우레탄폼 샌드위치 패널은 E class 로 나타났다.

컴퓨터 시뮬레이션을 통한 충격흡수시설의 개발 (Development of Crash Cushion by Computer Simulation)

  • 김동성;김기동;고만기
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.513-516
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    • 2008
  • The development of crash cushions is finally completed by full-scale vehicle crash tests. Since the current development of crash cushions is achieved by numerous repeated full-scale vehicle crash tests based on empirical and irrational methods, it requires a great amount of costs. In this research, the more rational procedure based on prototype design by static tests and computer simulation is suggested and it can minimize the number of full-scale vehicle crash tests.

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