• 한국지진공학회논문집
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• 제25권3호
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• pp.137-144
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• 2021

In this study, the seismic safety of nuclear power plant structures is evaluated and verified by performing a vibration test on a relatively simple shear wall structure. The shear walls are the prominent members of nuclear power plants and resist the seismic load. The shear wall structure is designed and manufactured to perform shaking table tests and is used to increase the accuracy of the analytical method by comparing them with the numerical analysis results. Different results will be checked and more efficient application methods will be studied depending on the method of designing reinforced concrete structures.

• Geomechanics and Engineering
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• 제19권3호
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• pp.229-240
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• 2019

The physical models are useful to understand the soil behaviour. Hence, these tools allow validating analytical theories and numerical data. This paper addresses the design, construction and implementation of a physical model able to simulate the soil liquefaction under different cyclic actions. The model was instrumented with a piezoelectric actuator and a set of transducers to measure the porewater pressures, displacements and accelerations of the system. The soil liquefaction was assessed in three different grain size particles of a natural sand by applying a sinusoidal signal, which incorporated three amplitudes and the fundamental frequencies of three different earthquakes occurred in Colombia. In addition, such frequencies were scaled in a micro shaking table device for 1, 50 and 80 g. Tests allowed identifying the liquefaction susceptibility at various frequency and displacement amplitude combinations. Experimental evidence validated that the liquefaction susceptibility is higher in the fine-grained sands than coarse-grained sands, and showed that the acceleration of the actuator controls the phenomena trigging in the model instead of the displacement amplitude.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.305-308
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• 2006

In this paper, the seismic performance of SRC piers for near fault motions was evaluated by shaking table tests on small scale models. Dead load of the superstructures was simulated by axial prestress at the center of the column section. A mass frame linked with steel bars was fabricated to include the effect of superstructure mass. Friction of the mass frame when it moves was minimized by special details and it was proved before tests. Five pier models with 400mm diameter were tested by increasing the acceleration of the near fault motion. Test results were discussed and compared with previous quasi-static tests.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.399-402
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• 1999

This study is about seismic performance of the EDF(Electricite De France) system, that is among various base isolator. We get solutions of equation of motion of this system for displacement, velocity, acceleration and compared with solutions using finite element program. And, through shaking table tests we will prove seismic performance

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.877-883
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• 2009

Shaking table tests are performed to evaluate the dynamic group pile effect in fine sand. Single pile tests and $2{\times}4$ group pile tests are performed on 3D pile spacing. Dynamic p-y backbone curves are obtained to evaluate dynamic group pile effect by using dynamic p-y curve of single pile. And dynamic group pile p-multiplier is estimated by dynamic p-y backbone curve. Dynamic p-multiplier can be calculated by using subground reaction ratio of dynamic p-y backbone curve which is the same displacement of p-y curve peak point As the result, dynamic group pile effects are evaluated in terms of a shaking frequency, a shaking acceleration, and a relative density. Dynamic group pile p-multiplier is the largest at lead pile, and the value decrease at middle pile and trail pile. p multiplier increases as increasing input acceleration and decreasing relative density. This results coincide with NCHRP's research which suggest p multiplier increases as increasing pile cap displacement.

• 한국지반환경공학회 논문집
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• 제20권12호
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• pp.15-26
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• 2019

본 연구에서는 게비온-식생토낭 옹벽에 대한 동적 특성을 평가하기 위해서 실대형 진동대 실험 시 토조 내부에 포설되는 흙과 식생토낭, 연결재, 게비온 등의 전단특성을 규명하고, 이 결과를 이용하여 실대형 진동대 실험을 수행하였다. 또한, 식생토낭벽체의 기울기, 지반가속도 등의 실험조건으로 실대형 진동대 실험을 실시하여 가속도, 변위, 토압에 대한 게비온-식생토낭 옹벽시스템의 동적 특성을 분석하였다. 결과, 1:0.3 기울기에서는 지진가속도가 $(0.154-0.44)g_n$일 때, 동적주동토압의 작용점은 저면으로 부터 (0.376-0.377)H인 것으로 나타났다. 1:1 기울기에서는 (0.389-0.393)H으로 나타나 기울기가 완만할수록 동적주동토압의 작용점은 높은 것으로 나타났다.

• 한국지반공학회지:지반
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• 제14권2호
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• pp.9-20
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• 1998

지진에 의한 지반의 액상화 현상으로 인하여 지하에 매설된 생활관거가 파괴될 가능성은 대단히 높다. 만일 지진이 발생하는 즉시 지반의 액상화 가능성을 판단할 수 있다면 관거가 파괴됨으로 인한 피해를 최소한으로 감소시킬 수 있다. 액상화 현상이 지반에 발생하는 동시에 이를 판별하기 위해서는 지표에서 진동의 이력을 측정함과 동시에 해석함으로써 가능하다. 본 논문에 서는 지표에서 측정된 가속도 기록을 통하여 지반의 액상화 가능성과 액상화된 지반의 두께를 평가하는 방법을 제시하고자 한다. 이를 위하여 실제로 측정된 지진 기록을 해석하고, 또한 진동대시험이 실시되었다. 이 결과 액상화 지반의 판별과 액상화된 지반의 두께는 지반 최대 가속도와 스펙트럼 강도로 결정할 수 있음이 증명되었다.

• Structural Engineering and Mechanics
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• 제22권6호
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• pp.761-783
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• 2006

The enlargement of interest in base isolators as an earthquake-proof design strategy has dramatically accelerated experimental studies of elastomeric bearings worldwide. In this paper, a new base isolator concept that is a hybrid system of rubber bearings is proposed. Uniaxial, biaxial, and triaxial shaking table tests are also performed to study the seismic behavior of a 0.4-scale three-story isolated steel structure in the National Center for Research on Earthquake Engineering in Taiwan. Experimental results demonstrate that structures with a hybrid system of rubber bearings composed of stirruped rubber bearings and laminated rubber bearings can actually decrease the seismic responses of the superstructure. It has been proved through the shaking table tests that the proposed hybrid system of rubber bearings is a very promising tool to enhance the seismic resistance of structures. Moreover, it is demonstrated that the proposed analytical model in this paper can predict the mechanical behavior of the hybrid system of rubber bearings and seismic responses of the base-isolated structures.

• Structural Monitoring and Maintenance
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• 제3권2호
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• pp.175-194
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• 2016

Based on the change of traditional viscoelastic damper structure, a brand-new damper is designed to control simultaneously the translational vibration and the rotational vibration for platforms. Experimental study has been carried out on the mechanical properties of viscoelastic material and on its multi-dimensional seismic response control effect of viscoelastic damper. Three types of viscoelastic dampers with different shapes of viscoelastic material are designed to test the influence of excited frequency, strain amplitude and ambient temperature on the mechanical property parameters such as circular dissipation per unit, equivalent stiffness, loss factor and storage shear modulus. Then, shaking table tests are done on a group of single-storey platform systems containing one symmetric platform and three asymmetric platforms with different eccentric forms. Experimental results show that the simulation precision of the restoring force model is rather good for the shear deformation of viscoelastic damper and is also satisfied for the torsion deformation and combined deformations of viscoelastic damper. The shaking table tests have verified that the new-type viscoelastic damper is capable of mitigating the multi-dimensional seismic response of offshore platform.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.107-114
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• 2001

When group pile supporting structures are to be subjected to large lateral loads, generally, hatter piles are used in group pile with vertical piles. It is well known that batter piles resist lateral static loads which are acted upon the piles as axial farces quite well but, they show a poor performance under seismic loads. However, it is not yet known how the batter piles behave under dynamic loading and how to strengthen the batter piles to improve the seismic performance. Shaking table tests were performed to investigate the seismic behavior of the batter pile and to bring up the countermeasures to improve the seismic performance. As the result of the shaking table tests, batter piles failed due to not only the excessive increase of compressive force near the pile head but also that of tensile force. In case that the pile head was connected with pile cap by rubber joint, the max. acceleration at the pile cap was reduced due to the high damping ratio of rubber and the max. moment and max. axial farce at the pile head was decreased remarkably. When the inclinations(V:H) of the batter pile were 8:3 and 8:4, max. moment, max. shear force, and max. axial farce were reduced notably and max. acceleration and max. displacement at the pile cap was diminished, too.