• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2006년도 학술발표회 논문집
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• pp.209-216
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• 2006

For evaluation of building performance, a nonlinear dynamic capacity of the building is a key parameter. In this study, an reinforced concrete special moment resisting frame building was chosen to study the process of determining the nonlinear dynamic capacity. The building, which was designed by IBC 2003 representing new codes, was composed of special moment resisting frames in the perimeter and internal frames inside the building. The capacity, which is inter-story drift capacity, consists of two categories, local and global collapses. Global collapse capacity was determined by incremental dynamic analysis. Local collapse capacity was determined by the same method except for utilizing damage index. In audition to this, it was also investigated that the effect of including internal frames designed by gravity load in the analysis. Results showed that the damage index is a useful tool for determining local collapse. Furthermore, including the internal frames with special frames in the analysis is very important in determining the capacity of a building so both must be considered at the same time.

• 한국지진공학회논문집
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• 제9권5호
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• pp.11-19
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• 2005

건축 구조물의 내진 설계는 탄성 정적 방법에 기초하고 있으나, 강진시 구조물의 실제 거동은 비탄성 동적이기 때문에 설계 규준의 적합성을 판단하기 위해서는 비탄성 동적 해석이 요구된다. 본 논문에서는 철근 콘크리트 특수 모멘트 저항 골조 건물을 선택하여 IBC 2003에 따라 설계한 후, 선택된 부재들의 최대 소성 회전, 소산 에너지를 구하여, 건물의 비탄성 거동이 규준에서 의도한 거동을 보이는 지를 검토함과 동시에 층간변위률 요구값을 구하여 설계 한도를 만족하는 지를 조사하였다. 더불어 비횡력 저항 시스템인 내부 모멘트 저항 골조의 해석시 포함 여부의 영향도 함께 조사하였다. 해석 결과 IBC 2003에 의해 설계된 건물은 규준이 의도한 비탄성 거동을 보여주었으며 층간변위률 또한 설계한도를 만족하였다. 그리고, 내부 모멘트 저항 골조는 지진 해석 결과에 중요한 영향을 미치므로 해석 모델에 반드시 포함되어야 함을 알수 있었다.

• Structural Engineering and Mechanics
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• 제27권6호
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• pp.671-682
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• 2007

The probability and the reliability-based seismic performance evaluation procedure proposed in the FEMA-355F was applied to a reinforced concrete moment frame building in this study. For the FEMA procedure, which was originally developed for steel moment frame structures, to be applied to other structural systems, the capacity should be re-defined and the factors reflecting the uncertainties related to capacity and demand need to be determined. To perform the evaluation procedure a prototype building was designed per IBC 2003, and inelastic dynamic analyses were conducted applying site-specific ground motions to determine the parameters for performance evaluation. According to the analysis results, distribution of the determined capacities turned out to be relatively smaller than that of the demands, which showed that the defined capacity was reasonable. It was also shown that the prototype building satisfied the target performance since the determined confidence levels exceeded the objectives for both local and global collapses.

• Steel and Composite Structures
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• 제47권4호
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• pp.489-502
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• 2023

The strong column-weak beam (SCWB) moment ratio is specified in AISC 341 to prevent an abrupt column sway in steel special moment frames (SMFs) during earthquakes. Even when the SCWB requirement is satisfied for an SMF, a column-sway can develop in the SMF. This is because the contribution of the composite beam action developed in the concrete floor slab and its supporting beams was not included while calculating the SCWB moment ratio. In this study, we developed a new method for calculating the SCWB moment ratio that included the contribution of composite beam action. We evaluated the seismic collapse performance of the SMFs considering various risk categories and building heights. We demonstrated that the collapse performance of the SMFs was significantly improved by using the proposed SCWB equation that also satisfied the target performance specified in ASCE 7.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.190-193
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• 2006

The definition of the Dual system is that the total seismic force resistance is to be provided by the combination of the moment frame and the shear walls or braced frames in proportion to their stiffness and the moment frame shall be capable of resisting at least 25% of the design force in Korean Building Code 2005 (KBC 2005). But, the definition of moment frame is ambiguous whether the moment frame include the imaginary columns in the shear wall (Case I) or include only the columns outside the shear wall (Case II). 60-story RC building was designed as dual system for Case I and Case II, and the required strength and reinforcement are compared. Moment and axial capacity of the shear wall of Case II decreased about 5% due to the absence of the column in the shear wall. The requirement of upper and bottom reinforcement of slab in Case II increased 13% and 40%, respectively, when compared to those of Case I. The required longitudinal reinforcement in columns for Case II is about 1.5 times larger than that of Case I.

• 한국지진공학회논문집
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• 제17권1호
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• pp.11-19
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• 2013

This research presents that seismic performance of steel moment resisting frame building designed by past provision(UBC, Uniform Building Code) before and after retrofitted with BRB (Buckling-Restrained Brace) was evaluated using response modification factor (R-factor). In addition, the seismic performance of the retrofitted past building was compared with that specified in current provision. The past building considered two different connections: bilinear connection, which was used by structural engineer for building design, and brittle connection observed in past earthquakes. The nonlinear pushover analysis and time history analysis were performed for the analytical models considered in this study. The R-factor was calculated based on the analytical results. When comparing the R-factor of the current provision with the calculated R-factor, the results were different due to the hysteresis characteristics of the connection types. After retrofitted with BRBs, the past buildings with the bilinear connection were satisfied with the seismic performance of the current provision. However, the past buildings with the brittle connection was significantly different with the R-factor of the current provision.

• 한국지진공학회논문집
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• 제11권2호
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• pp.39-45
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• 2007

본 연구에서는 확률과 신뢰성을 바탕으로 개발된 FEMA-355F의 내진성능 평가기법을 적용하여 철근 콘크리트 모멘트골조 건물의 내진성능을 평가하였다. 철골 구조물을 대상으로 개발된 FEMA의 성능평가 방식을 다른 구조 시스템에 적용할 때 각 시스템에 적합한 성능값을 결정해야하며, 요구값과 성능값 계산 시 수반되는 불확실성을 반영하는 계수들을 새로이 구해야 한다. 이를 수행하기 위해 예제 건물을 IBC 2003에 따라 설계한 후, 성능평가에 필요한 변수들을 결정하기 위해 건물의 위치에 적합한 지반운동을 이용하여 비탄성 동적 해석을 수행하였다. 해석결과에 따르면 계산된 성능값의 분포는 요구값에 비해 상대적으로 작았으며, 이 결과는 본 연구에서 결정된 성능값이 합리적임을 나타낸다. 구해진 신뢰도는 부분 및 전체 붕괴 모두에 대해 목표치를 초과하였으므로 예제 건물은 목표 성능을 만족하는 것으로 나타났다.

• 대한조선학회 특별논문집
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• 대한조선학회 2006년도 특별논문집
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• pp.77-80
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• 2006

In recent booming up of the ship building market, the supplying of large scale casting is difficult to keep the delivery schedule for ship yard because of the restrict manufacturer in Korea. And also, it is main cause to rise-up the cost of castings. This paper describes the outline of guidance of optimizing design for Rudder Horn Casting to reduce the risk of the delivery problem to ship yard.

• 산업기술연구
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• 제18권
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• pp.97-105
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• 1998

The most of the design engineers for construction has academic background of bachelors degree. Theories for advanced composite structures are too difficult for such engineers and some simple but accurate enough methods are necessary. The senior author has reported that some laminate orientations have decreasing values of $D_{16}$, $B_{16}$, $D_{26}$ and $B_{26}$ stiffnesses as the ply number increases. Such plates behave as special orthotropic plates and simple formulas developed by the author can be used. Most of the bridge and building slabs on girders have large aspect ratios. For such cases further simplification is possible by neglecting the effect of the longitudinal moment terms($M_x$) on the relevant partial differential equations of equilibrium. In this paper, the result of the study on the subject problem is presented.

• Earthquakes and Structures
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• 제25권2호
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• pp.79-87
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• 2023

Special moment resisting steel frame structures are now being used commonly in highly seismic regions as seismically reliable structures. However, a very important parameter describing the dynamics of steel structures during earthquake loading, Soil Structure Interaction (SSI), is generally neglected. In this study, the significance of consideration of flexibility of soil in being able to obtain a result closer to reality is asserted. The current paper focuses on calculation of seismic fragility curves special moment resisting steel frame structures under different earthquake loadings for fixed-base and SSI models. The observation of obtained fragility curves lead to the conclusion that the SSI has a considerable effect on component fragility for the steel structures, with its effects decreasing for higher peak ground acceleration. The results show that the structures when considered SSI have a higher probability of exceeding a damage limit state. This observation attests the role of SSI in the accurate study of structural performance.