• Title/Summary/Keyword: Dynamic response

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Wind-induced dynamic response and its load estimation for structural frames of single-layer latticed domes with long spans

  • Uematsu, Yasushi;Sone, Takayuki;Yamada, Motohiko;Hongo, Takeshi
    • Wind and Structures
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    • v.5 no.6
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    • pp.543-562
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    • 2002
  • The main purpose of this study is to discuss the design wind loads for the structural frames of single-layer latticed domes with long spans. First, wind pressures are measured simultaneously at many points on dome models in a wind tunnel. Then, the dynamic response of several models is analyzed in the time domain, using the pressure data obtained from the wind tunnel experiment. The nodal displacements and the resultant member stresses are computed at each time step. The results indicate that the dome's dynamic response is generally dominated by such vibration modes that contribute to the static response significantly. Furthermore, the dynamic response is found to be almost quasi-static. Then, a series of quasi-static analyses, in which the inertia and damping terms are neglected, is made for a wide range of the dome's geometry. Based on the results, a discussion is made of the design wind load. It is found that a gust effect factor approach can be used for the load estimation. Finally, an empirical formula for the gust effect factor and a simple model of the pressure coefficient distribution are provided.

Dynamic Response Analysis of Stiffened Plates Subjected Plates Subjected to Moving Loads (이동하중을 받는 보강판의 동응답해석)

  • 정정훈;정태영
    • Journal of KSNVE
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    • v.3 no.1
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    • pp.57-63
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    • 1993
  • The dynamic response of stiffened rectangular plate subjected to a concentrated force or mass moving at constant speed is analyzed by using finite- element method. Stiffened plates are modelled as an assembly of isotropic thin plate elements and equivalent Euler beam ones, in which the beam elements represent the stiffener effects concentrated at the attached lines of stiffeners to the plates. The Newmark's time integration method is used to obtain the dynamic response of stiffened plates. Numerical examples are given to verify the validity of the presented method and also to investigate the effects of speed and moving mass on the dynamic characteristics of stiffened plates.

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Effect of Analysis Method on Seismic Response for a Suspension Bridge (해석방법이 현수교 지진응답에 미치는 영향)

  • 김호경;유동호;이동일;이재홍
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.03a
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    • pp.422-429
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    • 2003
  • A comparative study was performed for a suspension bridge to grasp the possible differences in seismic responses evaluated by several analytical methods. The items mainly investigated are the linear vs. nonlinear response the response spectrum method vs. the linear dynamic analysis method and the damping ratio and it's implementation into analysis procedures. According to the numerical example, it is found that the seismic responses are considerably affected by the damping-related parameters even though slight differences are shown depending on the response quantities md the exciting directions. On the other hand, it is also confirmed that the seismic responses are less affected by the analysis method-related parameters such as the response spectrum method vs. the linear dynamic analysis method, and the linear and nonlinear analysis method. The response spectrum method is expected to give conservative results for the examined bridge, provided that the design response spectrum in the Korean Highway Design Specification is modified according to the proper damping ratio.

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A Study on the Frequency Response Characteristics of High Response Flow Control Servo Valve (고 응답 유량제어 서보밸브의 주파수 응답특성에 관한 연구)

  • 서종수;신유식;지명국;전영흥;정효민;정한식
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.6
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    • pp.480-488
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    • 2003
  • The purpose of this research Is to derive the principal design parameters governing the dynamic characteristics of the high response flow control servo valve. For this purpose, a numerical modeling of the servo valve system and a parameter sensitivity analysis to a frequency response characteristics was peformed. As a result of these analysis, a basis for improvement of a dynamic characteristics of servo valve was arranged.

The dynamic response prediction of the structure by transient vibration using Semi-Empirical Method (준 경험적 방법을 이용한 충격성 진동에 대한 구조물의 동적 응답의 예측)

  • Lee, Hong-Ki;Baek, Jae-Ho;Kim, Kang-Boo;Woun, Young-Jae
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1945-1950
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    • 2000
  • When one build a building that posses Precison production process to be sensitive to vibration and SMD to procuce a large dynamic force, how do one predict & answer vibration control problem at building structure design at first stage, That is a question. It has tried to predict dynamic response and establish answering about global or local dynamic problem in building using experimental and analysis method. One of such a try, it be proposed Semi-Empirial Method that reduce error element of input information about dynamic analysis using dynamic experimental study and measurement data in the basis of real-structure. In this paper, the dynamic response problem about RC-structure building that will be set-up SMD produce large transient dynamic force using Semi-Empirical Method.

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Dynamic Response of Reinforced Concrete Beams Following Instantaneous Removal of a Bearing Column

  • Tian, Ying;Su, Youpo
    • International Journal of Concrete Structures and Materials
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    • v.5 no.1
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    • pp.19-28
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    • 2011
  • This paper documents an experimental study of dynamic response of reinforced concrete beams following instantaneous removal of a bearing column. Four half-scale specimens representing two-span beam bridging across the removed column were tested. The test boundary conditions simulated rotational and longitudinal restraints imposed on a frame beam by the neighboring structural components. The gravity loads were simulated by attaching mass blocks on the beams at three locations. Dynamic loading effects due to sudden removal of a column were simulated by quickly releasing the supporting force at the middle of the specimens. The experimental study investigated the load-carrying capacity of beams restrained longitudinally at the boundaries and dynamic impact on forces. The tests confirmed the extra flexural strength provided by compressive arch action under dynamic loading. The tests also indicated that the dynamic amplification effects on forces were much lower than that assumed in the current design guideline for progressive collapse.

Experimental study of dynamic response of a slider(A Measurement of Slider Dynamic Using DFHT) (슬라이더의 동적거동에 대한 실험적 고찰(DFHT를 이용한 슬라이더의 동적거동 측정 방법))

  • 강태식;김재원;박노열
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.1117-1121
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    • 2001
  • The dynamic behavior of slider is investigated using Dynamic Flying Height Tester(DFHT). The dependence of slider's dynamic fluctuation on disk velocity is measured, and a comparison is made with the computational result.

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Dynamic response of middle slab in double-deck tunnel due to vehicle load (차량하중에 의한 복층터널 중간슬래브의 동적 응답)

  • Kim, Hyo-Beom;Kwak, Chang-Won;Park, Inn-Joon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.5
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    • pp.717-732
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    • 2017
  • Recently, the construction of underground structure such as a double-deck tunnel is increasing to manage rapid growth of roadway traffic volume. Double-deck tunnel includes middle slab to separate upper and lower road inside, and various sources affect the dynamic behaviour of middle slab due to dynamic loading of vehicle. Therefore, it is important to investigate the dynamic response of middle slab precisely to apply it to design and analysis of double-deck tunnel. In this study, dynamic analysis model of middle slab considering structural type, design velocity, vehicle load, and surface roughness, etc. is built. 3-dimensional dynamic analysis is performed to assess dynamic response of middle slab. Consequently, Dynamic Magnification Factor which represents dynamic response of middle slab shows maximum in case of elastomeric bearings (EB) and average roughness (Grade C). It is also expected that dynamic response can be reduced under the condition of good roughness (Grade B) and fixed bearings (FB).

Dynamic Response Analysis of 200m Honeycomb Lattice Domes by Rise Span Ratio (라이즈 스팬 비에 의한 200m 허니컴 래티스 돔의 동적 응답 분석)

  • Park, Kang-Geun;Chung, Mi-Ja
    • Journal of Korean Association for Spatial Structures
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    • v.19 no.2
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    • pp.51-61
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    • 2019
  • The objective of this study is to analysis the seismic response of 200m spanned honeycomb lattice domes under horizontal and up-down ground motion of El Centro earthquake. For the analysis of seismic response of the honeycomb lattice domes by rise/span ratio, the time history analysis is used for the estimation of the dynamic response. The low rise lattice dome is less deformed and less stressed than the high rise lattice dome for the earthquake ground motion. The 3-dimensional earthquake response is not significantly different the dynamic response of one directional ground motion. The earthquake response of domes with LRB isolation system is significantly reduced for the asymmetric vertical deformation and the horizontal and vertical accelerations.

Development of the Educational Simulator for Aircraft Dynamic Characteristic Analysis with the State-Space Method (상태.공간 방식에 의한 항공기 동특성 해석 교육 시뮬레이터 개발)

  • Yoon, Sun-Ju
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.17 no.1
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    • pp.9-16
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    • 2009
  • The analysis of an aircraft flight dynamics is recently very convenient because of the introduction of state-space method and a well-developed package software. The representation of a dynamic system is described as a simple form of matrix calculation and the unique form of model is available for the linear or nonlinear, time variant or time invariant, mono variable or multi variable system with state-space method. And this analysis can be simplified with the specific functions of a package software and it is very simplified to execute the simulation of the dynamic characteristics for an aircraft model with an interactive graphical treatment. The purpose of this study is to develope an educational flight simulator for the students who need to analyze the dynamic characteristics of an aircraft that is primarily to execute the simulation for the analysis of the transient response and frequency response of an aircraft stability. Furthermore the dynamic characteristics of an aircraft motion is set up as dynamical animation tool for the control response on 3-axis motions of an aircraft.

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