• Title/Summary/Keyword: Tunnel model

Search Result 2,217, Processing Time 0.026 seconds

The Smoke Propagating Distance in the Reduced-scale Model for a Subway Railroad Tunnel (축소 모형을 이용한 지하철터널에서의 연기전파거리 측정)

  • Kim, Myung-Bae;Choi, Byung-Il;Oh, Chang-Bo;Han, Yong-Shik
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.7 no.4
    • /
    • pp.295-304
    • /
    • 2005
  • The smoke propagating distances are measured in case that a fire occurs within the subway railroad tunnel. The tunnel is 800m long and the dimension of the cross-section is. Three vertical shafts exist for smoke ventilation. The experiments are performed using the 1/50 reduced-scale model. The smoke propagating distances are measured by thermocouples and by visualization for the accuracy. In order to understand the effect of a fire size and ventilation capacity of the shafts on the smoke propagating distance, 9 test scenarios are chosen. Based on the results, the smoke propagating distance is shown to be important criteria for the ventilation design of the tunnel.

  • PDF

Wind tunnel model studies to predict the action of wind on the projected 558 m Jakarta Tower

  • Isyumov, N.;Case, P.C.;Ho, T.C.E.;Soegiarso, R.
    • Wind and Structures
    • /
    • v.4 no.4
    • /
    • pp.299-314
    • /
    • 2001
  • A study of wind effects was carried out at the Boundary Layer Wind Tunnel Laboratory (BLWTL) for the projected 558-m high free-standing telecommunication and observation tower for Jakarta, Indonesia. The objectives were to assist the designers with various aspects of wind action, including the overall structural loads and responses of the Tower shaft and the antenna superstructure, the local wind pressures on components of the exterior envelope, and winds in pedestrian areas. The designers of the Tower are the East China Architectural Design Institute (ECADI) and PT Menara Jakarta, Indonesia. Unfortunately, the project is halted due to the financial uncertainties in Indonesia. At the time of the stoppage, pile driving had been completed and slip forming of the concrete shaft of the Tower had begun. When completed, the Tower will exceed the height of the CN-Tower in Toronto, Canada by some 5 m.

Components of wind -tunnel analysis using force balance test data

  • Ho, T.C. Eric;Jeong, Un Yong;Case, Peter
    • Wind and Structures
    • /
    • v.18 no.4
    • /
    • pp.347-373
    • /
    • 2014
  • Since its development in the early 1980's the force balance technique has become a standard method in the efficient determination of structural loads and responses. Its usefulness lies in the simplicity of the physical model, the relatively short records required from the wind tunnel testing and its versatility in the use of the data for different sets of dynamic properties. Its major advantage has been the ability to provide results in a timely manner, assisting the structural engineer to fine-tune their building at an early stage of the structural development. The analysis of the wind tunnel data has evolved from the simple un-coupled system to sophisticated methods that include the correction for non-linear mode shapes, the handling of complex geometry and the handling of simultaneous measurements on multiple force balances for a building group. This paper will review some of the components in the force balance data analysis both in historical perspective and in its current advancement. The basic formulation of the force balance methodology in both frequency and time domains will be presented. This includes all coupling effects and allows the determination of the resultant quantities such as resultant accelerations, as well as various load effects that generally were not considered in earlier force balance analyses. Using a building model test carried out in the wind tunnel as an example case study, the effects of various simplifications and omissions are discussed.

Study on Statistical Method for Objective Evaluation of Tunnel Portal Slopes (객관적인 터널 갱구사면 평가를 위한 통계기법 연구)

  • Kwon, O-Il;Baek, Yong;Na, Jong-Hwa;Seo, Yong-Seok;Kim, Gyo-Won
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.03a
    • /
    • pp.634-643
    • /
    • 2006
  • This study was intended to develop a high reliable technique by statistically processing on-site data with a general linear model, providing the basic data for construction, analysis of stability and establishment of maintenance measures for tunnel portal slopes in the future. This study evaluated the stability of a tunnel portal slope using a quantified technique, which is based on a general linear model. The important scores of each independent variable were allocated by using the ranges of the quantified values, based on the predicted coefficient of regression and the scores for categories of each independent variable were allocated so that those are equally spaced. The quantification model obtained from the results of evaluating the total data used for the quantification process provided precise results. In addition, it is expected that a more detail subdivision of response variables and sufficient data would produce a better stability evaluation standard.

  • PDF

Nonlinear simulation of tunnel linings with a simplified numerical modelling

  • Zhao, Huiling;Liu, Xian;Bao, Yihai;Yuan, Yong
    • Structural Engineering and Mechanics
    • /
    • v.61 no.5
    • /
    • pp.593-603
    • /
    • 2017
  • A high-efficiency simplified modelling approach is proposed for investigating the nonlinear responses of reinforced concrete linings of shield tunnels. Material and geometric nonlinearities are considered in the analysis of the lining structures undergoing large deformation before ultimately losing the load-carrying capacity. A beam-spring element model is developed to capture the force-transfer mechanism between lining segments and radial joints. The developed model is validated by comparing analyzed results to experimental results of a single-ring lining structure under two loading conditions: the ground overloading and the lateral unloading respectively. The results show that the lining structure under the lateral unloading due to excavation on the both sides of the tunnel is more vulnerable compared to the case of ground overloading on the top of the tunnel. A parameter study is conducted and results indicate that the lateral pressure coefficient has the greatest influence on the behaviour of the lining structure.

Wind Tunnel Test of an Unmanned Aerial Vehicle (UAV)

  • Chung, Jin-Deog;Lee, Jang-Yeon;Sung, Bong-Zoo;Koo, Sa-Mok
    • Journal of Mechanical Science and Technology
    • /
    • v.17 no.5
    • /
    • pp.776-783
    • /
    • 2003
  • A low speed wind tunnel test was conducted for full-scale model of an unmanned aerial vehicle (UAV) in Korea Aerospace Research Institute (KARI) Low Speed Wind Tunnel(LSWT). The purpose of the presented paper is to illustrate the general aerodynamic and performance characteristics of the UAV that was designed and fabricated in KARI. Since the testing conditions were represented minor portions of the load-range of the external balance system, the repeatability tests were performed at various model configurations to confirm the reliability of measurements. Variations of drag-polar by adding model components such as tails, landing gear and test boom are shown, and longitudinal and lateral aerodynamic characteristics after changing control surfaces such as aileron, flap, elevator and rudder are also presented. To explore aerodynamic characteristics of an UAV with model components build-up and control surface deflections, lift curve slope, pitching moment variation with lift coefficients and drag-polar are examined. The discussed results might be useful to understand the general aerodynamic characteristics and drag pattern for the given UAV configuration.

MSBS-SPR Integrated System Allowing Wider Controllable Range for Effective Wind Tunnel Test

  • Sung, Yeol-Hun;Lee, Dong-Kyu;Han, Jong-Seob;Kim, Ho-Young;Han, Jae-Hung
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.18 no.3
    • /
    • pp.414-424
    • /
    • 2017
  • This paper introduces an experimental device which can measure accurate aerodynamic forces without support interference in wide experimental region for wind tunnel test of micro aerial vehicles (MAVs). A stereo pattern recognition (SPR) method was introduced to a magnetic suspension and balance system (MSBS), which can eliminate support interference by levitating the experimental model, to establish wider experimental region; thereby MSBS-SPR integrated system was developed. The SPR method is non-contact, highly accurate three-dimensional position measurement method providing wide measurement range. To evaluate the system performance, a series of performance evaluations including SPR system measurement accuracy and 6 degrees of freedom (DOFs) position/attitude control of the MAV model were conducted. This newly developed system could control the MAV model rapidly and accurately within almost 60mm for translational DOFs and 40deg for rotational DOFs inside of $300{\times}300mm$ test section. In addition, a static wind tunnel test was conducted to verify the aerodynamic force measurement capability. It turned out that this system could accurately measure the aerodynamic forces in low Reynolds number, even for the weak forces which were hard to measure using typical balance system, without making any mechanical contact with the MAV model.

Flight Control Experiment of High-Speed Aero-Levitation Electric Vehicle Scale-Model in Wind-Tunnel (공기부상 초고속 운행체 축소모델의 풍동내 비행제어 실험)

  • Park, Young-Geun;Choi, Seung-Kie;Cho, Jin-Soo;Song, Yong-Kyu
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.11 no.3
    • /
    • pp.246-253
    • /
    • 2005
  • An experimenal study on flight control of high-speed AEV(Aero-levitation Electric Vehicle) scale model in wind-tunnel is conducted. The AEV is to fly at very low altitude in predesigned track so that it is always under the wing-in-ground effect. The experiment is intended to fly the scale model to follow the predesigned altitude schedule while holding its attitude (pitch, roll, and yaw). Especially, the altitude changes for climb, cruise, and descent with constant pitch angle are most important maneuvers. The experiment shows that the required mission flights can be performed with appropriate sensors, processors, and actuators.

Analysis and Structural Behavior of Shield Tunnel Lining Segment (쉴드터널 라이닝 세그멘트의 해석과 거동 특성)

  • Lee, Hwan-Woo;Kim, Gwan-Soo;Kim, Gwang-Yang;Kang, Dae-Hui
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2007.04a
    • /
    • pp.757-762
    • /
    • 2007
  • The lining segment which is the main structure of the shield tunnel consists of joints, not continua. Past international and domestic design data have been commonly used for design practices without specific verification about the structural analysis model, design load, and affection of the soil constant of the lining segment. In this study, the propriety is estimated through the comparison between analytical solution and numerical solution for segment analysis and design models of the shield tunnel which is being used internationally and domestically. As a result, the full. circumferential beam jointed spring model (1R-S0) is suggested by considering aspects of convenient use, application to field condition, and accuracy of analysis result. With suggested model, the parameter analysis was conducted for joint stiffness, ground rigidity, joint distribution, and joint number.

  • PDF

Wind tunnel experiments of a building model incorporating viscous-damping walls

  • Pan, Austin D.E.;Yeung, Ngai
    • Wind and Structures
    • /
    • v.4 no.3
    • /
    • pp.261-276
    • /
    • 2001
  • This paper presents an experimental study on the effectiveness of viscous-damping walls in controlling the wind-induced vibrations of a building model. A simple four-story building model, square in plan, was constructed for wind tunnel study. In this paper the description of the model, its instrumentation, and the experimental set-up and methodology are reported. The effectiveness of viscous-damping walls in reducing vibrations was investigated for different fluid levels in the walls, and at varying wind speeds and attack angles. The results show that viscous-damping walls are highly effective in most cases.