• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.301-306
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• 2000

Small passenger and car carrier ships are mainly used as a connection way between land and small islands. And these ships should be designed to enlarge the capacity of passenger and car loading within limited space and draft. So the resonances of various vibrations exist in normal operation range of engine and propulsion shafting. In this paper, hull's superstructure vibration which was especially induced by the 1st order excitation of whirling vibration on the 2-engines and 2-propulsion shafting systems is introduced. Also these are verified via the theoretical analysis using transfer matrix method and FEA software ANSYS and its vibration measurement.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.465-472
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• 2003

The main concept of base isolation system is to reduce the member forces by decreasing the earthquake forces transmitted to superstructure instead of the conventional techniques of strengthening the structural members. There are two important advantages in friction pendulum systems. The functions of carrying the vertical load and of providing horizontal stiffness are effectively separated. This results in a more stable system that eliminates the need of a fail-safe mechanism. Friction pendulum systems are less sensitive to variations in the frequency content of ground excitation and tend to limit the intensity of the farce imparted to the superstructure. This study investigates the friction coefficients on the FPS test specimens according to the velocity, bearing pressure and test waveform.

• Structural Engineering and Mechanics
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• 제85권1호
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• pp.81-88
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• 2023

This paper begins by analyzing cable vibrations due to external excitations and their effects on the overall dynamic behavior of cable-stayed bridges. It is concluded that if the natural frequency of a cable approaches any natural frequency of the bridge, the cable loses its rigidity and functionality. The results of this analysis explain the phenomenon that occurred on the Dubrovnik Bridge in Croatia during a storm and measures for its retrofit. A field test was conducted before the bridge was opened to traffic. It was concluded: "The Bridge excited unpleasant transverse superstructure vibration with the frequency of approximately 0.470 Hz. Hence, it seems possible that a pair of stays vibrating in phase may excite deck vibrations". Soon after this Bridge opened, a storm dumped heavy damp snow in the area, causing the six longest cable stay pairs of the main span to undergo large-amplitude vibrations, and the superstructure underwent considerable displacements in combined torsion-sway and bending modes. This necessitated rehabilitation measures for the Bridge including devices to suppress the large-amplitude vibrations of cables. The rehabilitation and monitoring of the Bridge are also presented here.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.606-614
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• 2005

This paper deals with new realizations of research, scientific development, managerial and economic optimizations for prefabricated building systems. In the literature, all scientific fields are worked out based on the efficiencies, costs, benefits, choice of execution design, technical demands, aesthetical point of view, as well as the total economics. In the present example of a school-building for communities in the third world, the following criteria have been regarded: The optimal superstructure of prefabricated concrete building systems; the particularity of countries of the Third World (e.g. the climate, the political and the economic conditions); the time for construction and necessary innovative developments for an economically optimized superstructure. Added to this are alternative construction-methods and costs for a simple but variable system which can be adapted to changing functions, where variability should be the main point. For example, a school building that is to be adapted by varying number of rooms to cater for the growing number of pupils.

• Earthquakes and Structures
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• 제26권1호
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• pp.1-15
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• 2024

Isolation technology has been proven effective in reducing the seismic response of superstructures, where most of the deformation is concentrated in the isolation layer. However, in cases of earthquakes with intensities surpassing the fortification level of the area, or severe near-fault earthquakes, the isolation layer may experience excessive deformation, resulting in damage to the isolation bearings or collisions with the retaining wall or surrounding buildings. In this study, a finite element model using ABAQUS is established and compared with experimental test results to deeply investigate the influence of limit devices on the isolation layer and its response to the superstructure. The findings reveal that a larger limiter stiffness and a smaller reserved gap can achieve a more effective limiting effect. Nevertheless, a smaller reserved gap and a larger limiter stiffness may result in increased response of the superstructure. Therefore, rational selection of the reserved gap and limiter stiffness is crucial to reduce the acceleration response.

• 콘크리트학회지
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• 제22권4호
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• pp.68-71
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• 2010

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 2000년도 춘계학술대회
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• pp.43-43
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• 2000

• 한국공간구조학회지
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• 제9권2호
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• pp.5-10
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• 2009

• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.39.4-39
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• 1998

• 한국지진공학회논문집
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• 제9권5호
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• pp.21-28
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• 2005

본 논문에서는 상부구조물과 진동대에서 측정된 가속도를 이용하여 구조물과 지반의 동적 상호작용을 고려한 진동대 시험을 수행하는 방법이 제안된다. 부분구조법을 기반으로 한 제안된 실험법은 상부구조물만을 실험체로 사용하고 지반모델에 대해서는 동적지반강성을 진동대 제어기에 반영하는 방법이다. 이 때, 실험부분인 상부구조물은 전체 구조물 지반계의 동적거동을 모사하기 위한 운동으로 진동대에 의해 가진된다. 먼저, 구조물 지반계의 운동방정식으로부터 유도된 수치 시뮬레이션 검증모델에 의해 제안된 방법의 타당성이 검증된다. 또한, 진동대의 전달함수를 고려한 시뮬레이션 모델로부터 진동대 시험에 의한 제안된 방법의 적용성이 수치 시뮬레이션에 의해 검증된다.