• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.355-360
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• 2001

Design requirements for the nuclear fuel assembly grid of the pressurized light water reactor(PLWR) are scrutinized from the mechanical/structural point of view. As a result of the scrunity, mechanical/structural test facilities on the spacer grid of the PLWR Fuel are set up in KAERI to find out their mechanical/structural performance.

• 한국농공학회논문집
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• 제50권1호
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• pp.49-57
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• 2008

This study evaluated the flexural properties and fire resistance of polyolefm based structural synthetic fiber reinforced concrete. The effects of differing fiber length, dimension and fiber volume fraction were studied. Flexural and fire resistance test were conducted in accordance with the JCI SF-4 and RABT time heating temperature curve, respectively. The Flexural test results indicated that the polyolefln based structural fiber reinforcement showed an ability to increase the flexural toughness and good fire resistance significantly(as compared to steel fiber reinforcement).

• Structural Engineering and Mechanics
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• 제52권5호
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• pp.875-887
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• 2014

The aim of the shaking table experiment is to verify the isolation effect of a storage liquid tank with multiple friction pendulum bearings. A 1:20 scale model of a real storage liquid tank that is widely used in the petroleum industry was examined by the shaking table test to compare its anchored base and isolated base. The seismic response of the tank was assessed by employing the time history input. The base acceleration, wave height and tank wall stress were used to evaluate the isolation effect. Finally, the influences of the bearing performance that characterizes the isolated tank, such as the friction force and residual displacement, were discussed.

• Structural Engineering and Mechanics
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• 제69권1호
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• pp.77-93
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• 2019

Although much research has been carried out using recycled aggregates sourced from normal strength concrete, most of the buildings to be demolished are constructed with low strength concrete. Therefore, the properties of the concrete incorporating recycled aggregates, sourced from the waste of structural elements cast with low strength concrete, were investigated in this study. Four different concrete mixtures were designed incorporating natural and recycled aggregates with and without fly ash. The results of the mechanical and durability tests of the concrete mixtures are presented. Additionally, full-scale one-way reinforced concrete slabs were cast, using these concrete mixtures, and subjected to bending test. The feasibility of using conventional reinforced concrete theory for the slabs made with structural concrete incorporating recycled aggregates was investigated.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.389-394
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• 2011

Existing FPS(Friction Pendulum System) is isolation system which is possible to isolate structures by pendulum characteristic from ground vibration. Structural natural frequency could be decided by designing the radius of curvature of FPS. Thus, response vibration could be reduced by changing natural frequency of structures from FPS. But effective periods of recorded seismic wave were various and estimation of earthquake characteristic could be difficult. If effective periods of seismic wave correspond to natural frequency of structures with FPS, resonance can be occurred. Therefore, CFPBS(Cone-type Friction Pendulum Bearing System) was developed for controlling the response acceleration and displacement by the slope of friction surfaces. Structural natural frequency with CFPBS can be changed according to position of ball on the friction surface which was designed cone-type. Therefore, Divergence of response could be controlled by CFPBS which had constantly changing natural frequency with low modal participation factor in wide-range. In this study, Seismic performance of CFPBS was evaluated by numerical analysis and shaking table test.

• 한국지진공학회논문집
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• 제17권4호
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• pp.151-157
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• 2013

In this study, an externally reinforced structural system for SMC(Sheet Molding Compound) panel water tank, designed according to the Japanese design code, is experimented to evaluate its seismic performance. The test tank is 3m long, 2m wide and 3m high, considering the capacity and size of the shaking table. The measured hydrodynamic pressures are found to be approximately 70% of the Japanese design code values. It may be partially due to the convex shape effect of the unit panels. The analytical results of externally reinforced system based on the measured dynamic water pressures are found in good agreement with the test results. If the design hydrodynamic pressures are estimated properly, the proposed analytical model for the externally reinforced water tank becomes a useful design tool and the Japanese design code is found to provide a safe design for the external frames of SMC panel water tank.

• 한국건설순환자원학회논문집
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• 제2권4호
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• pp.321-327
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• 2014

경량골재콘크리트는 구조물의 자중경감을 목적으로 경량골재를 적용하여 제조한 콘크리트로 구조물의 고층화 및 대형화에 효과적으로 대응할 수 있는 장점이 있다. 하지만 경량골재는 다공체이므로 화재와 같은 고온에 노출되는 경우 수증기압이나 열응력에 의해 골재 주변으로 응력이 집중될 가능성이 커 폭렬이 발생하기 쉽다. 본 연구는 구조용 경량골재를 사용한 1종 경량골재콘크리트의 함수율과 내화특성과의 관계를 검토코자 하며, 실험결과 압축강도와 함수율이 높은 경량골재콘크리트는 폭렬의 가능성이 높기 때문에 흡수율이 작은 골재의 사용이나 폭렬방지를 위한 대책이 필요하다.

• 국제초고층학회논문집
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• 제2권3호
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• pp.271-283
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• 2013

This paper introduces the current status of high-rise building design in Japan, with reference to some recent projects. Firstly, the design approval system and procedures for high-rise buildings and structures in Japan are introduced. Then, performance-based wind-resistant design of a 300 m-high building, Abeno Harukas, is introduced, where building configuration, superstructure systems and various damping devices are sophisticatedly integrated to ensure a higher level of safety and comfort against wind actions. Next, design of a 213 m-high building is introduced with special attention to habitability against the wind-induced horizontal motion. Finally, performance-based wind-resistant design of a 634 m-high tower, Tokyo Sky Tree, is introduced. For this structure, the core column system was adopted to satisfy the strict design requirements due to the severest level of seismic excitations and wind actions.

• 대한건축학회논문집:구조계
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• 제34권7호
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• pp.3-10
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• 2018

Steel fiber reinforced concrete can improve the resistance to cracking by adding steel fibers when mixing concrete. It can reduce the temperature and shrinkage cracks, and its flexural performance can be improved by increasing the effective moment of inertia. In this study, the deck-plate was used to replace the concrete form and reinforcing bars, and the steel fiber reinforced concrete was used to control the shrinkage and temperature cracks, and improve the flexural performance of the slab. Total 9 slab specimens were tested for analyzing the structural performance and serviceability. As a results, flexural capacity of the slab with deck-plate was evaluated to be superior to that of the normal reinforced concrete slab specimens with the same tensile reinforcement. The steel fiber reinforced concrete was found to have about 8% flexural capacity increase depending on the steel fiber content $15.7kg/m^3$. Also, in terms of flexural stiffness, the specimens using steel fiber reinforced concrete for the same parameters were evaluated to have a stiffness increase of about 30% compared with the case of using ordinary concrete. Especially, it was found that the stiffness of the test results was significantly higher than the analytical result because the increase of the tensile strength of the steel fiber reinforced concrete is not reflected in the current structural code.

• Structural Engineering and Mechanics
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• 제17권2호
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• pp.187-201
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• 2004

A shaking table test on a three-story one-bay steel frame model with metallic yield dampers and their parallel connection with oil dampers is carried out to study the dynamic characteristics and seismic performance of the energy dissipation system. It is found from the test that the combined energy dissipation system has favorable reducing vibration effects on structural displacement, and the structural peak acceleration can not evidently be reduced under small intensity seismic excitations, but in most cases the vibration reduction effect is very good under large intensity seismic excitations. Test results also show that stiffness of the energy dissipation devices should match their damping. Dynamic analysis method and mechanics models of these two dampers are proposed. In the analysis method, the force-displacement relationship of the metallic yield damper is represented by an elastic perfectly plastic model, and the behavior of the oil damper is simulated by a velocity and displacement relative model in which the contributions of the oil damper to the damping force and stiffness of the system are considered. Validity of the analytical model and the method is verified through comparison between the results of the shaking table test and numerical analysis.