• Title/Summary/Keyword: 진동대 실험

Search Result 372, Processing Time 0.029 seconds

Identification of Stiffness and Damping Matrix of Building Structures using Modal Characteristics (모드 특성을 이용한 건축 구조물의 강성 및 감쇠 행렬식별)

  • 강경수
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.8 no.2
    • /
    • pp.45-53
    • /
    • 2004
  • In this paper, the stiffness and damping matrix are experimentally constructed using the structural modal information on frequencies, damping ratio and modal vectors, which are obtained by shaking table tests. Free vibration, harmonic and white noise vibration tests are performed. The acceleration of the shaking table was used as the input signal, and the corresponding accelerations of each floor were measured as output signals. The characteristics and limitations of modal information from each test are compared. The results of this study would be a basic resource of the analytical and experimental studies on the system identification of structures.

The analysis of RC bridge piers on shaking table test by using Nonlinear program (비선형 해석프로그램을 이용한 RC교각의 진동대 시험 분석)

  • Yang, Dong-Wook;Park, Young-Kwon;Lee, Yeon-Hun;Chung, Young-Soo;Lee, Dae-Hyoung
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2009.05a
    • /
    • pp.67-68
    • /
    • 2009
  • This research aims at investigating the seismic behavior of RC bridge piers subjected to NFGM in low or moderate seismic region according to Volumetric Confinement Steel Ratio through the shaking table test unlike original way of the test. This investigation deal with the estimate with SARCF for shaking table test by the comparative analysis for the value of FFT.

  • PDF

Analysis of Seismic Behaviour of Cut and Cover Tunnel according to backfill materials (뒤채움재 특성별 개착식 터널의 동적 거동 특성 연구)

  • Kim, Nag-Young;Lee, Seung-Ho;Lee, Yong-Jun;Kim, Jung-Ho
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.7 no.2
    • /
    • pp.177-186
    • /
    • 2005
  • World widely, the occurrences of earthquakes have been increased recently including to nations which earthquake often happen to like Japan. Taking into account that the earthquake acceleration at design was 0.154 g at the contigency level earthuake (CLE) with its geological condition, it resulted that this method must be the most efficient condition against the earthquake vibration to two lane cut-and cover tunnel. The correlations between the result of the shaking table test and its numerical analysis showed that the test data of the bending stress due to the earthquake vibration have been underestimated about 5 percents in case of the cut slope 1 : 0.6 and about 10 percent in case of the cut slope 1 : 1.2. However, on average, the results showed a similar tendency that the higher the height of the backfill of the EPS block was, the less the bending stress was.

  • PDF

Development and Shaking Table Tests of a Base Isolator for Controling Subway Train-Induced Vibration of a Steel Building (지하철 진동에 대한 철골건물 기초진동 절연장치의 개발 및 진동대 실험)

  • Kim, Jin-Koo;Song, Young-Hoon;Kwun, Hyong-Oh;Huh, Young
    • Journal of KSNVE
    • /
    • v.7 no.5
    • /
    • pp.789-796
    • /
    • 1997
  • In this study a conventional rubber mount and a new form of base isolator made of steel spring coated with natural and articial rubber were manufactured and tested on a shaking table to investigate the capacity of reducing the vertical vibration of a building induced by subway train. The model structure used in the test is a 1/4 scaled steel structure, and a white noise input and train vibration records were used to check the effectiveness of the isolators. According to the results all three types of isolators turned out to perform effectively in reducing the acceleration and the natural rubber-coated one is ranked best among the isolators. However the vertical displacement of the model is increased due to the instolation of the bearings, and the safty against the lateral load induced by earthquake ground motion should be provided to be able to apply the system to the real buildings.

  • PDF

Seismic Performance Evaluation of Concrete Anchors used in Power Plant Equipment by Shaking Table Tests (진동대 실험을 통한 발전기기용 콘크리트 앵커의 성능평가)

  • Lee, Sang-Moon;Jeon, Bub-Gyu;Jung, Woo-Young
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.41 no.1
    • /
    • pp.21-28
    • /
    • 2021
  • The main purpose of this study is to assess the safety of the fixed anchorages subjected to the seismic motion for an operating facilities in the actual power plant. Thus, the experimental study was conducted to investigate the load response in the event of an actual seismic to the anchorages of a nonstructural components. Since there are economic and spatial constraints to study nonstructural components that actually have various forms, alternative test specimens of steel frames with mass were built and the shaking table test was carried out. In order to evaluate the dynamic characteristics and seismic performance, the natural frequency of the target structure was identified through the shaking table test and then the load response characteristics of the anchorage were evaluated by generating an artificial seismic effect like actual seismic. Finally, the structural stiffness was reinforced by fixing the steel frame to the test specimen using bolts, thereby reducing the load transmitted to the anchorage. It will be carried out on the reliability verification of the experiments and areas that have not been carried out due to the site conditions through the analytical approach in the future.

Shaking Table Test for Seismic Performance Evaluation of Non-Seismic Designed Wall-Type Apartment (내진설계 되지 않은 공동주택의 진동대 실험에 의한 내진성능 평가)

  • Chung, Lan;Lee, Joung-Woo;Park, Tae-Won
    • Journal of the Korea Concrete Institute
    • /
    • v.18 no.6 s.96
    • /
    • pp.721-728
    • /
    • 2006
  • Earthquakes are reported thai building structures have been colossal damaged, but before 1988 designed structures which were not applicate seismic design code have no seismic performance. Especially, for the apartment structures were indicated that it have no resist wall element of earthquake before 1988 designed structures. We have to evaluate for seismic performance this structures, therefore it will be retrofitted for seismic index sufficient structures. We performed seismic performance evaluation for model structures by MIDAS which is general structure analysis software. In this study, it was performed shaking table test to evaluate model structure which is reinforcement concrete and 5 floors for seismic performance index. We made specimens by similar's law and tested shaking table test. In the shaking table test it is not performed prototype model test because of space and equipment condition. So we had made scale-down model for 1/5 by similar's law. That's why it needs for the evaluation of performance. However, it is not possible to do an experiment of prototype owing to the shortage of space and the limit of an experimental instrument in the shaking table test. Then, modeling and reducing the part of prototype do the experiment. In this experiment a shaking table test is done and seismic performance of model structures is evaluated by using similitude laws for scale down specimen. As a result it is proved that non-seismic design structures need to retrofit since seismic performance shows life safe grade in 0.12g of an earthquake.

Seismic Response Estimation of Water Extinguishing Facilities using Shaking Table Tests (진동대 실험을 통한 수계 소화설비의 지진응답평가에 관한 연구)

  • Nam, Min-Jun;Park, Seung-Hee;Kim, Dong-Joon;Choi, Jun-Sung
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.16 no.4
    • /
    • pp.9-18
    • /
    • 2012
  • In this study, a shaking table test was performed for the evaluation of water extinguishing facilities. Water extinguishing facilities, such as a general pipe, a seismic pipe (Loof type) and a pump, were used in the experiment. This captured the dynamic characteristics of water extinguishing systems by earthquake records at El-Centro with a 50%, 70%, 100%, 120% level. As a result, seismic type facilities have excellent seismic performance compared to general facilities. By using the acceleration response spectrum, not only is the performance evaluation of water extinguishing facilities able to be determined, but also the deformation of facilities in low earthquake levels can be known. This proposed approach can determine the seismic performance evaluation of water extinguishing facilities and verify seismic performance criteria.

Evaluation of Inertial Interaction of a Multi-degree-of-freedom Structure during a Large-scale 1-g Shaking Table Test (대형 진동대 실험을 이용한 다자유도 구조물의 관성 상호작용 평가)

  • Chae, Jonghoon;Yoon, Hyungchul;Jung, Jongwon
    • Journal of the Korean Geotechnical Society
    • /
    • v.38 no.6
    • /
    • pp.17-28
    • /
    • 2022
  • The effect of the soil-structure interaction (SSI) on has been recently evaluated in shaking table tests. However, most of these tests were conducted on single-degree-of-freedom (SDOF) superstructures and a single-pile. This study investigates the inertial interaction effect of a multi-degree-of-freedom (MDOF) superstructure system with a group piles on a large-scale shaking table test. Whereas the SDOF superstructure system shows a single-frequency amplification tendency, the MDOF superstructure system exhibited amplification tendencies of the acceleration phase and frequency responses for multiple frequencies. In addition, the amplification phenomenon between the footing and the column-type superstructure exceeded that between the footing and the wall-type superstructure, indicating a greater inertial interaction effect of the column-type superstructure. The relationship between shear force and inertial force, the relative vertical and horizontal displacements on the footing was figured out. Also, the ananlysis of dynamic p-y curve at each depth was conducted. In summary, the MDOF and SDOP superstructure systems exhibited different behaviors and the column-type superstructure exerted a higher interaction effect than the wall-type superstructure.

Shaking Table Test of a 1/10 Scale Isolated Fifteen-story Flat Plate Apartment Building (면진층을 가지는 1/10 축소된 15층 무량판 아파트건물의 진동대 실험)

  • Chun, Young-Soo
    • Land and Housing Review
    • /
    • v.2 no.3
    • /
    • pp.287-297
    • /
    • 2011
  • This paper presents the results of performance verification tests of the isolated flat plate apartment building with the laminated rubber bearings. The shaking table test is carried out in CABR(China Academy of Building Research) with two 1/10 scale isolation and non-isolation models under 4 excitation waves. The shaking table test is proceeding from x axis, y axis and x+y axis with different amplitude of acceleration values. The results show that, to non-isolated model, the natural vibration period is remarkably decreased and entered non-linear condition after moderate earthquake. Its accelerations become lager with increasing storey number and completely collapsed under large earthquake. The inter-storey shifts largely exceed the limit values of regulated displacement angles. But to isolated model, the natural vibration period of isolated modal is almost the same in all conditions and still in its elastic condition. The earthquake loading is greatly reduced and the accelerations of superstructure are greatly reduced. The inter-storey drifts are very small and can be neglected. The isolated model is in translational state and can be seen as a rigid whole. The displacements of isolation layer are in the allowable range. This experiment demonstrates that the seismic isolation is very effective to mitigate the influence of earthquake on structures and it is possible to increase the serviceability due to decrease the floor acceleration. facilities from their good states that is superior to non-isolated structure.

The Vibration Comfort Evaluation of the Shaking Table Mass Foundation (진동대 반력기초의 진동사용성 평가)

  • Choi, Hyoung-Suk;Jung, Da-Jung;Kim, Seong-Do;Cheung, Jin-Hwan
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.15 no.2
    • /
    • pp.53-60
    • /
    • 2011
  • When designing building structures, dynamic serviceability is one of the most important items. Much research is being carried out on machine vibrations that affect inside residents and expensive equipment in the building structure. The vibration effect generally depends on the mass ratio, and an adequate mass ratio is determined by comparison with the serviceability limit according to the criteria. This study investigates the evaluation of vibration serviceability by using ISO 2631 to confirm the propriety of adequate mass ratios and it is verified that the application of a complicated FE model to model the real large shaking table facility with the mathematical model simulated as a SDOF system. The weighted RMS value is then compared with the comfort limit given by ISO 2631. As a result, the analysis of the numerical model is consistent with analysis of the FE model. Moreover, it is found that the adequate mass ratio of the concrete foundation and shake table, considering the self-weight of the real facility, should be less than 0.013. It is also confirm that the sample facility is satisfies the requirement of an adequate mass ratio.