• Structural Engineering and Mechanics
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• 제21권1호
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• pp.83-100
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• 2005

This paper presents results from a study to extend a performance-based shearwall selection procedure to take into account the contributions of nonstructural finish materials (such as stucco and gypsum wallboard), construction quality issues, and their effects on the displacement performance of engineered wood shearwalls subject to seismic loading. Shearwall performance is evaluated in terms of peak displacements under seismic loading (characterized by a suite of ordinary ground motion records) considering different combinations of performance levels (drift limits) and seismic hazard. Shearwalls are analyzed using nonlinear dynamic time-history analysis with global assembly hysteretic parameters determined by fitting to actual shearwall test data. Peak displacement distributions, determined from sets of analyses using each of the ground motion records taken to characterize the seismic hazard, are postprocessed into performance curves, design charts, and fragility curves which can be used for risk-based design and assessment applications.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.375-382
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• 1999

The fundamental vibration period of a shearwall apartments cannot estimate accurately by means of empirical formulas specified in present codes, The objective of this paper is to estimate the period of a shearwall apartments by microtremor measurement. A micretremor is the continuous small oscillation of the ground cause by traffic and operation machinery. Microtremors are extensively studied primarily in Japan to estimate conveniently subsurface structures of soil deposits and building vibrations. It is obtained the results that the fundamental periods estimated by microtremor measurement are shorter than those values by dynamic analysis of building.

• 콘크리트학회논문집
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• 제12권4호
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• pp.3-14
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• 2000

Structural performance of the walls subjected to lateral load reversals depends on various parameters such as loading history, sectional shape, reinforcement, lateral confinement, aspect ratio, axial compression, etc. Thus, the performance of the shearwall for wall-type apartment should be evaluated properly considering above parameters. This study investigates the effect of sectional shape on the structural performance of the wall. Sectional shape of the specimen is rectangular, barbell and T. Based on this experimental results, all specimens behaved as ductile fashion and failed by concrete crushing of the compression zone. Deformation index of those specimens evaluated better than 3 of ductility ratio, and 1.5% of deformability specified by seismic provision. Moreover, the performance of the rectangular shaped specimen, whose compression zone was confined with U-bar and cross tie, was as good as the barbell shaped specimen. Therefore, if we considered construction practice such as workmanship and detailing, shearwall with rectangular section may be more economical lateral load resisting system.

• 한국지진공학회논문집
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• 제18권1호
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• pp.53-61
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• 2014

RC shear wall sections which have irregular shapes such as T, ㄱ, ㄷ sections are typically used in low-rise buildings in Korea. Pushover analysis of building containing such members costs a lot of computation time and needs professional knowledge since it requires complicated modeling and, sometimes, fails to converge. In this study, a method using an equivalent column element for the shear wall is proposed. The equivalent column element consists of an elastic column, an inelastic rotational spring, and rigid beams. The inelastic properties of the rotational spring represent the nonlinear behavior of the shearwall and are obtained from the section analysis results and moment distribution for the member. The use of an axial force to compensate the difference in the axial deformation between the equivalent column element and the actual shear wall is also proposed. The proposed method is applied for the pushover analysis of a 5- story shear wall-frame building and the results are compared with ones using the fiber elements. The comparison shows that the inelastic behavior at the same drift was comparable. However, the performance points estimated using the pushover curves showed some deviations, which seem to be caused by the differences of estimated yield point and damping ratios.

• 한국안전학회지
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• 제19권4호
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• pp.161-165
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• 2004

철근콘크리트조 공사의 안전성과 효율성은 동바리-슬래브거푸집의 최적의 운영에 달려있다. 철근콘크리트공사에서의 사고는 주로 가설공사에 과도한 하중이 작용하였거나 동바리를 조기에 철거하기 때문에 발생한다. 콘크리트의 조기압축강도발현이 공사중구조체의 안전에 중요하다. 슬래브-동바리의 상호작용에 관한 연구는 주로 무량슬래브 구조에 대하여 이루어 졌다. 본 연구에서는 전단벽식 철근콘크리트조 아파트에서 슬래브와 동바리에서의 하중분포를 유한요소법을 이용하여 조사하였다.

• 대한토목학회논문집
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• 제5권1호
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• pp.123-132
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• 1985

기초지반(基礎地盤)의 유연성(柔軟性)은 구조물의 지진응답(地震應答)에 지대한 영향(影響)을 미치게 된다. 본 연구(硏究)에서는 지반(地盤)에 대한 상부구조물(上部構造物)의 상대강도(相對剛度)가 지반(地盤)-구조물(構造物) 상호작용(相互作用)에 미치는 영향을 분석하였다. 해석(解析)모델로서는 기초(基礎)슬래브의 형태와 규격은 동일하지만 상부구조(上部構造)의 강성(剛性)이 상대적으로 큰 전단벽구조(剪斷壁構造)와 강성(剛性)이 작은 뼈대 구조(構造)로 된 건물에 대하여 지반과 연계(連繫)된 집중질량(集中質量)모델을 작성하였으며, 운동방정식(運動方程式)의 해석을 위해서는 Roesset의 모드감쇠(減衰)(Modal Damping)를 이용하는 모드중첩법(重疊法)을 사용하였다. 연구결과(硏究結果), 전단벽구조물(剪斷壁構造物)의 경우 대부분의 지반조건에 대하여 지반(地盤)-구조물(構造物) 상호작용(相互作用)의 영향이 현저하게 나타나는 반면 뼈대구조물(構造物)의 경우 유연성지반(柔軟性地盤)을 제외하고는 지반(地盤)-구조물(構造物) 상호작용(相互作用)의 영향이 공학적(工學的)으로 무시될 수 있음을 확인하였다. 또 지반(地盤)-구조물(構造物) 상호작용(相互作用)의 영향이 증가(增加)할수록 구조물 상부(上部)에서의 지진응답(地震應答)이 감소(減少)하는 반면 구조물 하부(下部)에서의 지진응답(地震應答)은 오히려 증가(增加)한다는 사실을 알 수 있었다.

• Wind and Structures
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• 제9권3호
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• pp.217-230
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• 2006

This paper describes a procedure to develop fragility curves for woodframe structures subjected to lateral wind loads. The fragilities are cast in terms of horizontal displacement criteria (maximum drift at the top of the shearwalls). The procedure is illustrated through the development of fragility curves for one and two-story residential woodframe buildings in high wind regions. The structures were analyzed using a monotonic pushover analysis to develop the relationship between displacement and base shear. The base shear values were then transformed to equivalent nominal wind speeds using information on the geometry of the baseline buildings and the wind load equations (and associated parameters) in ASCE 7-02. Displacement vs. equivalent nominal wind speed curves were used to determine the critical wind direction, and Monte Carlo simulation was used along with wind load parameter statistics provided by Ellingwood and Tekie (1999) to construct displacement vs. wind speed curves. Wind speeds corresponding to a presumed limit displacement were used to construct fragility curves. Since the fragilities were fit well using a lognormal CDF and had similar logarithmic standard deviations (${\xi}$), a quick analysis to develop approximate fragilities is possible, and this also is illustrated. Finally, a compound fragility curve, defined as a weighted combination of individual fragilities, is developed.

• 한국지진공학회논문집
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• 제17권1호
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• pp.33-41
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• 2013

Due to a high level of system ductility, steel moment resisting frames have been widely used for lateral force resisting structural systems in high seismic zones. Earthquake field investigations after Northridge earthquake in 1994 and Kobe earthquake in 1995 have reported that many steel moment resisting frames designed before 1990's had suffered significant damages and structural collapse. In this research, seismic performance assessment of steel moment resisting frames designed in accordance with the previous seismic provisions before 1990's was performed. Buckling-restrained braces and shear walls are considered for seismic retrofit of the reference buildings. Increasing stiffness and strength of the buildings using buckling-restrained braces and shear walls are considered as options to rehabilitate the damaged buildings. Probabilistic seismic performance assessment using fragility analysis results is used for the criteria for determining an appropriate seismic retrofit strategy. The fragility contour method can be used to provide an intial guideline to structural engineers when various structural retrofit options for the damaged buildings are available.

• 콘크리트학회논문집
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• 제12권6호
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• pp.119-126
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• 2000

Reinforced concrete structural walls are widely known to provide an efficient lateral load resistance and drift control. However, many reported researches on them are mostly limited to the RC structural walls reinforced according to seismic details. When the pushover analysis technique is used for the prediction of inelastic behavior of frame-wall structures for the seismic evaluation of existing buildings having non-seismic details, the reliability of this analysis method should be checked by the test results. The objective of this study is to verify the correlation between the experimental and analytical responses of a high-rise reinforced concrete frame-wall structure having non-seismic details by using DRAIN-2DX program[11] and the test results performed previously[1]. It is concluded that the behavior of the frame-wall model is mainly affected by the fixed-end rotation(uplift at base) and bending deformation of the wall and that the analysis with the LINKS model[10] in DRAIN-2DX describes them with good reliability.

• 한국지진공학회논문집
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• 제18권4호
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• pp.181-191
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• 2014

This research presents the nonlinear analysis model for reinforced concrete shear wall systems with special boundary elements as proposed by the Korean Building Code (KBC, 2009). In order to verify the analysis model, analytical results were compared with the experimental results obtained from previous studies. Established analytical model was used to perform nonlinear static and dynamic analyses. Analytical results showed that the semi-special shear wall improved significantly the performance in terms of ductility and energy dissipation as expected based on previous test results. Furthermore, nonlinear incremental dynamic analysis was performed using 20 ground motions. Based on computer analytical results, the ordinary shear wall, special shear wall and newly proposed semi-special shear wall systems were evaluated based on the methods in FEMA P965. The results based on the probabilistic approaches accounting for inherent uncertainties showed that the semi-special shear wall systems provide a high capacity/demand (ACMR) ratio owing to their details, which provide enough capacity to sustain large inelastic deformations.