• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.1
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• pp.1-6
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• 2002

In order to study the characteristics of fiber reinforced bearing, the steel plates of laminated rubber bearing were replaced with fibers which have same effects of steel plates. The comparison of vertical test and horizontal test of laminated rubber bearing and fiber reinforced bearing shows that the effective damping of fiber reinforced bearing is higher than laminated rubber bearing. This result implies the high energy dissipation ability of fiber reinforced bearing under earthquake excitation. These fiber reinforced bearing can be applied to the low-coast building.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.520-525
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• 1997

액체금속로의 안전성과 경제성을 향상시키는데 중요한 요소로 부각된 면진설계기술을 개발하기 위하여 고감쇠 면진베어링의 축소모델을 제작하고, 성능확인을 위한 다양한 시험을 실시하였다. 면진베어링의 성능을 나타내는 전단강성, 감쇠특성, 항복하중특성값, 전단변형능력 등에 대한 시험결과 전단강성은 목표값에 비하여 작았지만 감쇠값과 전단변형은 목표값에 근접하였다. 이를 이용한 면진 원자로건물의 지진응답을 분석한 결과 면진베어링은 건물의 지진응답 가속도를 대폭 줄여주는 것으로 나타났다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.04a
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• pp.116-121
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• 1994

지금까지 대형 구조물에 널리 사용되고 있는 Base Isolator는 특히, 지진하중에 대하여 상부 구조물의 지반분리(base isolation)을 이용한 지진제어를 목적으로 하기 때문에 Seismic Isolator라 한다. 일반적으로 면진베어링에는 LRB(Laminated Rubber Bearing) 방식과 R-FBI(resilient-friction base isolator) 방식으로 크게 나눌 수 있다. LRB 방식은 가장 널리 사용되는 면진베어링으로써 방진고무를 주된 재료로 하고 수직강성을 보강하기 위하여 steel plate를 조합하여 제작하며, 초기강성 및 에너지 소산능력을 증가시키기 위하여 단면중앙에 납(lead plug)를 삽입하기도 한다. R-FBI 방식은 방진고무 적층판 내부에 미끄럼판을 가지고 있으므로 LRB 방식에 비하여 더 큰 수평변위를 발생시킬 수 있다. 이번에 설계 제작한 면진베어링은 LNG 저장탱크의 Seismic Isolation을 목적으로 적용대상의 사양에 맞추어 설계 제작하고 성능평가 시험을 수행하여 LNG 저장탱크, 원자로, 대형 건축물등 지진으로부터 보호되어야 하는 대형구조물의 방진재로 적용할 수 있는가를 평가하고자 한다. 본 논문에서는 제작된 면진베어링의 설계를 검증하고 방진고무(HDR)재료의 물리적 특성시험, 축소모델에 의한 정적, 동적시험을 통하여 시험방법을 소개하고 이러한 시험결과를 기초로 하여 면진베어리의 성능을 평가하였으며, 면진베어링의 온도변화, 외부 수직하중의 변화등에 따른 특성변화와 LNG 저장탱크와 면진베어링의 체결방법에 따른 시험으로 체결방법을 검증하였으며, 대상물의 사양에 적합한가를 고찰하였다.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.409-416
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• 2002

In order to apply seismic isolators to the low-cost buildings, seismic isolators have to be low-cost and light. In this paper fiber reinforced strip form isolator in which the steel plates of conventional rubber bearing was replaced by fiber was proposed. The proposed fiber reinforced strip form isolator was designed, fabricated, cut and subjected to vertical test and harizontal test. Therefore fiber reinforced strip form isolator was to be shown valid in the view point of fabrication and application to desired size. The harizontal test and vertical test have shown that fiber reinforced strip form isolator could replace the rubber isolator. By these results, low-cost and light seismic isolator can be applied to the low-cost building. These fiber reinforced strip form isolator can be applied to the low-cost building.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.987-992
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• 1995

본 논문에서는 복잡한 Hysteretic 복원력-변형률 특성을 갖는 고감쇠 면진베어링에 대한 Hysteretic bi-linear 모델을 사용하여 비교적 해의 정확성을 보장할 수 있는 Runge-Kutta 방법으로 지진해석을 위한 공식을 유도하였다. 그리고 Hysteretic bi-linear 모델을 사용한 면진베어링의 응답해석결과로부터 등가선형모델을 구하여 각각의 모델에 대한 지진응답 특성들을 비교분석하였다. 고감쇠 면진베어링을 전형적인 경수로원자로모델에 적용한 결과 면진구조물은 비면진 구조물에 비하여 가속도응답이 크게 감소함을 알 수가 있었다. 또한 면진베어링의 Hysteretic bi-linear 모델을 사용한 지진응답해석은 등가선형모델에 비하여 최대 변위응답특성은 유사하나 가속도응답은 크게 나타났다.

• Journal of Korean Society of Steel Construction
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• v.16 no.1 s.68
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• pp.145-153
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• 2004

Conventional lead-rubber bearings may be unstable in case of strong ground motions. To address this problem, this paper proposed a new concept of isolation device wherein shape memory alloy wires were incorporated in an elastomeric bearing. A three-span continuous steel bridge was used for seismic analyses to compare the performance of lead-rubber and proposed bearings. The proposed bearings showed almost the same performance as the lead-rubber bearings. In particular, the proposed bearings limited relative displacement effectively with strong ground motions and recovered its original undeformed shape.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.507-514
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• 2007

This paper summarizes the results of a research on the isolate effects and economical efficiencies of seismic isolation design compared with the existing earthquake-resistant design, and presents seismic performance of the base isolation system consisting of sliding-type bearing and lead rubber bearing (LRB) compared with that consisting of the LRB only. From the results of the research, it is verified that seismic isolation is very effective to mitigate the influence of earthquake on structures and it is possible to increase the serviceability due to decrease of the floor acceleration. Also, from the point of view of reduction of story acceleration and base shear, the base isolation system consisting of sliding-type bearing and LRB is more effective than that with LRB only. In respect of economical efficiency, special care should be taken in using this method since costs which have to be paid in proportin to increased performance are high.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.5 s.39
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• pp.65-77
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• 2004

In this study, the base isolation systems for equipment in the NPP are presented and the responses of each isolation system are investigated. As for the base isolation systems, a natural rubber bearing (NRB) and a high damping rubber bearing (HDRB) are selected. As input motions, artificial time histories enveloping the US NRC RG 1.60 spectrum and the probability-based scenario earthquake spectra developed for the Korean nuclear power plant site as well as a typical near-fault earthquake record are used. Uniaxial, biaxial, and triaxial excitations are conducted with PGAs of 0.1, 0.2 and 0.25g. The reduction of the seismic forces transmitted to the equipment models are determined for different isolation systems and input motions.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.1
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• pp.47-62
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• 1998

The laminated elastomeric bearing and the lead-rubber bearing were designed to isolate one bay-two story steel frame which is designed for only gravity load. The seismic performance is evaluated for the designed steel frame before and after application of these seismic isolators between the super structure and the foundation. These isolators can improve the seismic capacity of the steel frame. Especially, by inserting the lead plug into the center of the laminated elastomeric bearing, the initial stiffness of th bearing can be increased, thus rather large lateral displacement can be prevented under the frequent service lateral load. During the strong earthquake, yielding of the lead can increase the capacity of the energy dissipation.

• Land and Housing Review
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• v.4 no.2
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• pp.185-192
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• 2013

This study presents application effects of hybrid seismic isolation system to realize high seismic performance for low-rise lightweight buildings through a non-linear analysis and onsite experiments. The complex seismic isolation system applied in this study is a method of mixing sliding bearing and laminated rubber bearing in order to overcome limitation of laminated rubber bearing in increasing natural period of the whole seismic isolation system. As a result of the non-linear analysis, seismic isolation buildings designed with complex seismic isolation system are safe because its maximum response displacement is within allowable design displacement even for a strong earthquake which rarely occurs and its maximum response shear is less than design seismic force. As a result of the onsite experiment, the rigidity of seismic isolation stories corresponds to approximately 95.8% of the design equivalent stiffness value. This indicates that actual properties of the whole seismic isolation system correspond to design values.