• International journal of steel structures
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• v.18 no.4
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• pp.1167-1176
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• 2018

Steel cylindrical tanks are widely used for the storage of hazardous substances of which leakage must be prevented under any circumstances. However, the dynamic response of the steel cylindrical liquid storage tank depends sensitively on the fluid-structure interaction and the vibration of the tank structure and necessitates clarification for the safety of the tank structure. This paper presents the results of shaking table tests performed to examine the dynamic behavior of a scaled cylindrical steel tank model considering the presence or not of fixed roof and added mass at the top of the tank for various fluid levels. The test results confirm the occurrence of both beam-type and oval-type vibration modes and show that the larger content of liquid inside the container amplified the acceleration along the height of the cylindrical tank. The oval-type vibration modes are seen to be more dominant in case of large water-to-structure mass ratio.

• International journal of steel structures
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• v.18 no.4
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• pp.1420-1430
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• 2018

Earthquakes of 5.8 and 5.4 Richter scale recently occurred one after another in Korea, changing the Korean peninsula from an earthquake safe zone but 'earthquake danger zone'. Therefore, seismic reinforcements must expand to include structures with low seismic resistance in order to prepare for earthquakes on a larger scale in the future. This study investigated the performances of various seismic reinforcement systems such as X-braced steel rod reinforcement, steel shear wall with circular opening reinforcement, and slit damper reinforcement using shaking table test and computational analyses of seismic data in order to establish a proper seismic reinforcement plan. These three seismic reinforcement systems could increase the stiffness and strength of existing structures and reduce maximum drift ratio in the event of an earthquake.

• Journal of Korean Association for Spatial Structures
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• v.22 no.3
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• pp.41-48
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• 2022

The purpose of this study is to evaluate seismic performances of a modular house system developed by a simple 4-clip fastening method and double metal assembly made of lightweight metals. In order to evaluate structural and non-structural seismic performances of the system. Shaking table test was carried out with full-scale modular units, and a nonlinear pushover analysis was performed to obtain suitable seismic responses for story drifts, displacements, force resistances and dynamic properties of the system. Through 3D analysis and shaking table test, the current method of lightweight modular metal unit assembly and systems with seismic performance of a 4-clip fastening type modular house were demonstrated safe and effective to seismic design.

• Journal of Korean Port Research
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• v.14 no.3
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• pp.341-351
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• 2000

This study is on the purpose that the influence caused by noise and shaking through construction works shall be ranged to the fishing species of fishing area of the surface of sea. This study have been performed through analysis of physical effect by the value of noise and shaking test. The resulted purpose of this study has been carried out regarding whether influence factor of the fishing species and others are related or not as per the noise and shaking. For the purpose of the survey of noise and shaking, observances have been performed regarding the direct water surface of fishing area are as well as undersea. As for this result, the influence area for the injury at the fishing area caused by the noise and shaking have been stretched out to the distance of 10km from the source of sound. In this conclusion, this study is regarded as the reference basis of the compensation of injury for the species of fish and others in fishing area.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1345-1356
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• 2021

Damage to nuclear power plants causes human casualties and environmental disasters. There are electrical facilities that control safety-related devices in nuclear power plants, and seismic performance is required for them. The 2016 Gyeongju earthquake had many high-frequency components. Therefore, there is a high possibility that an earthquake involving many high frequency components will occur in South Korea. As such, it is necessary to examine the safety of nuclear power plants against an earthquake with many high-frequency components. In this study, the shaking table test of electrical facilities was conducted against the design earthquake for nuclear power plants with a large low-frequency components and an earthquake with a large high-frequency components. The response characteristics of the earthquake with a large high-frequency components were identified by deriving the amplification factors of the response through the shaking table test. In addition, safety of electrical facility against the two aforementioned types of earthquakes with different seismic characteristics was confirmed through limit-state seismic tests. The electrical facility that was performed to the shaking table test in this study was a motor control center (MCC).

• Journal of the Earthquake Engineering Society of Korea
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• v.28 no.3
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• pp.141-147
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• 2024

Earthquakes of magnitude 3.0 or greater occur in Korea about 10 times on average yearly, and the number of earthquakes occurring in Korea is increasing. As many earthquakes have recently occurred, interest in the safety of nuclear power plants has increased. Nuclear power plants are equipped with many cabinet-type control facilities to regulate safety facilities, and function maintenance is required during an earthquake. The seismic performance of the cabinet is divided into structural and functional performances. Structural performance can be secured during the design procedure. Functional performance depends on the vibration performance of the component. Therefore, it is necessary to confirm the seismic performance of the components. Generally, seismic performance is confirmed through seismic simulation tests. When checking seismic performance through seismic simulation tests, it is difficult to determine the effect of frequency and maximum acceleration on an element. In this paper, shaking table tests were performed using various frequencies and various maximum accelerations. The seismic performance characteristics of the functions of electrical equipment components were confirmed through tests.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.04a
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• pp.188-195
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• 1998

The main objective of this study is to observe the effect of visco-elastic damper on seismic behavior of structure. A small shaking table was designed and manufactured using the materials and machinery available in the market by the authors. Also, two small-scale models with and without visco-elastic dampers were made. Dynamic characteristics, such as natural periods and damping ratios, were measured with free vibration tests. Finally, the earthquake simulations tests by using this shaking table were performed to these models. Based on the test results, the effect of visco-elastic damper on the seismic response of models is evaluated.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.755-758
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• 2010

본 연구에서는 토목구조물에 대하여 상사율을 고려한 1g 진동대실험(Shaking Table Test)과 전산해석을 수행하여, 실제 지진하중(단주기, 장주기, 인공지진)에 대한 토목구조물의 안정성을 분석 및 평가 하였다. 상사율에 따른 지표면 가속도 거동을 비교 분석하기 위하여 여러 가지 상사율을 적용한 실험을 수행하여 측정된 결과와 전산해석 결과를 상호 비교 분석하여 상사비에 따른 실험결과의 적절성을 평가하였다. 상사율을 1/50과 1/50보다 크게 조성하여 진동대실험과 전산해석 결과에 의하면, 지표면 가속도의 결과는 모두 유사한 결과를 보였다. 상사율 1:50 이상인 단면의 경우 진동대실험과 전산해석 결과 사이의 유사성이 떨어지는 것으로 볼 때, 1:50 이하인 상사단면이 실제 현장에서의 거동을 모사하는데 더 높은 신뢰성을 제공하는 것으로 판단된다.

• Geotechnical Engineering
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• v.12 no.6
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• pp.51-64
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• 1996

After the model open-ended pile attached with strain gages was driven into a pressure chamber, in which the saturated microfine sand was contained, the static compression loading test was performed for that pile. Based on the test results, ultimate pile capacity was determined. Then, either simulated earthquake shaking or sinusoidal shaking was applied to the pile with the sustained certain level OP ultimate pile load. Then, pile capacity degradations characteristics during shaking were studied. Pile capacity degradation during two different shakings were greatly different. During the simulated earthquake shaking, capacity degradation depended upon the magnitude of applied load. When the load applied to the pile top was less than 70% of ultimate pile capacidy, pile capacity degradation rate was less than 8%, and pile with the sustained ultimate pile load had the degradation rate of 90%. Also, most of pile capacity degradation was reduced in outer skin friction and degradation rate was about 80% of ultimate pile capacity reduction. During sinusoidal shaking, pile capacity degradation did not depend on the magnitude of applied load. It depended on the amplitude and the frequency , the larger the amplitude and the fewer the frequency was, the higher the degradation rate was. Reduction pattern of unit soil plugging (once depended on the mode of shaking. Unit soil plugging force by the simulated earthquake shaking was reduced in the bottom 3.0 D, of the toe irrespective of the applied load, while reduction of unit soil plugging force by sinusoidal shaking was occurred in the bottom 1.0-3.0D, of the toe. Also, the soil plugging force was reduced more than that during simulated earthquake shaking and degradation rate of the pile capacity depended on the magnitude of the applied load.

• Journal of the Earthquake Engineering Society of Korea
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• v.1 no.1
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• pp.51-56
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• 1997

The objective of this study is to review the current state of earthquake simulation tecniques using the shaking table and check the reliability. One degree-of-freedom(d.o.f) and three d.o.f aluminium shear models were used and $4m{\times}4m$ 6 d.o.f shaking table was excitated in one horizontal direction to simulate 1940 El centro earthquake accelerogram (NS component). When the actual acceleration history of shaking table is compared to the desired one, it can be found that the overall histories are very similar, but that the lower frequency range (0~2 Hz) of the actual excitation has generally lower amplitude than that of the desired in Fourier transform amplitude. Free vibration and white noise tests have shown almost the some values for natural frequencies, but shown quite different values for damping rations, that is, 1.37% in case of free vibration test vs 14.76 % in case of white noise test. The time histories of story shear driff show the globally linear elastic behaviors. But the elliptical shape of the histories with one of the axis being the stiffness of the story implies the effect of viscous damping.