• Structural Engineering and Mechanics
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• v.40 no.4
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• pp.489-500
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• 2011

The elastic seismic response of plan-asymmetric multi storey steel-frame buildings is investigated under earthquake loading with particular emphasis on forward-rupture directivity and fling records. Three asymmetric building systems are generated with different torsional stiffness and varying static eccentricity. The structural characteristic of these systems are designed according to UBC 97 code and their seismic responses subjected to a set of earthquake records are obtained from the response history analysis (RHA) as well as the linear static analysis (LSA). It is shown that, the elastic torsional response is influenced by the intensity of near-fault ground motions with different energy contents. In the extreme case of very strong earthquakes, the behaviour of torsionally stiff buildings and torsionally flexible buildings may differ substantially due to the fact that the displacement envelope of the deck depends on ground motion characteristics.

• Journal of Korean Library and Information Science Society
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• v.9
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• pp.85-113
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• 1982

The information material in the library or in the information service center is at once its own property and the national resources, so that every citizen in the country has the right to the equal use of it for the development of the country. Library co-operation enables every citizen to use easily and equally the materials in the library. In the informational society of today, owing to the information explosion, the increase in the various user's demand of the information, and the rise of the cost of information material, even the richest and highly advanced country cannot be self-sufficient. Under these circumstances, the international co-operation among libraries seems to be the best way to solve the difficulties of selfsufficiency. Therefore, this paper aims to study the background of IFLA founded in 1927 in order to promote the international library co-operation and its development up to 1970's since its establishment, and, by introducing IFLA's programs of UBC, ISBD, and UAP, to consider the significance of IFLA's contribution to the development of library and librarianship.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.757-762
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• 2000

The purpose of this study is to investigate the performance of slab-beam-column subassemblage in the Ordinary Moment Frame(OMF). For this purpose, 3-story building was designed according to UBC and ACI building code(ACI 318-99) and the subassemblages of in the first story were constructed. The subassemblages were classified into interior and exterior. Each interior and exterior subassemblage is modeled by the 2/3 scale experimental specimens. All the specimens have the transverse beam and the columns on the slab have the lap splice as the typical exterior and interior slab-beam-column subassemblage. The interior subassemblage was tested under the constant axial force, while the exterior subassemblage was tested under the fluctuating axial force. Based on the results of the experiments, the performance of each subassemblage is evaluated and the failure mode is investigated.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.140-143
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• 2003

Recently, many high-rise reinforced concrete (RC) bearing wall structures of multiple occupancy have been constructed, which have the irregularities of weak (or soft) story and torsion at the lower stories simultaneously. The study compared the eccentricity of such a building predicted by design codes, EC 8, IBC 2000 and UBC 97, and by the test results through a series of shaking table tests of 1:12 model. Based on the comparison of the predicted eccentricity and the test result, the conclusions are drawn as follow: Accidental torsion due to the uncertainty on the properties of structure can be reasonably predicted by using the dynamic analysis with the center of mass being shifted by 5 percent of the dimension of the building perpendicular to the direction of the excitations than by using equivalent lateral force procedure

• Structural Engineering and Mechanics
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• v.9 no.3
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• pp.257-268
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• 2000

The seismic design recommendations of the Jordan Code for Loads and Forces (JC) are evaluated, based on comparisons with analytical studies and the Uniform Building Code. It was established that the overall safety ensured by the implementation of these recommendations is not consistent with the established seismic risk in Jordan and the intended objectives of the code. A new zoning map is proposed with effective peak ground acceleration values. The different period formulae of the code were studied and were found to grossly underestimate the fundamental period when compared with analytically derived values or other codes' formulae. Other factors including the dynamic, soil, importance and behavior factors are discussed. It was determined that the JC's lateral load distribution formulae clearly lead to smaller internal forces than both dynamic analysis and UBC loads, even when those loads are normalized to give the same base shear. The main reason for this is attributed to the limited allowance for a backlash force in the JC.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.2
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• pp.23-31
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• 2001

지반 위에 세워진 구조물의 지진응답해석시 지반-구조물 상호작용 영향은 지반으 선형특성을 고려하여 간주되었는데 최근 연구결과에 의하면 구조물 지진해석에서 연약지반의 비선형 특성이 중요한 요소로서 인식되었다. 하지만 지반-구조물계의 복잡한 비선형 특성 때문에 내진설계 기준에서 비선형 지반특성을 고려하기에는 아직도 어려움이 많다. 이 논문에서는 UBC 지반종류 $S_{D}$ 지반 위에 놓인 중규모의 얕은 온통기초와 묻힌 온통기초위에 세워진 건물에 대한 단자유도계 선형 지진해석을 연약지반의 비선형성을 고려하여 최대가속도가 0.17g 과 0.36g 인 Taft E-W 및 El Centro N-S 지진기록을 사용하여 수행하였다. 비선형 지진해석을 결과를 선형해석 결과와 비교하였을 때, 비선형 응답스펙트럼의 최대가속도가 지반의 비선형성 때문에 상당히 줄어드는 것으로 나타나 지반의 비선형성을 고려한 더효율적인 내진설계의 가능성을 보여준다.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.3
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• pp.55-65
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• 2000

구조물 지진해석을 위한 구조물 -지반 상호작용 해석에서도 비선형 지반 특성을 고려한 비선형해석이 요구되고 있어 구조물 비선형 지진 해석을 위해 기초 지반에 대한 수평방향 비선형 해석을 수행하였다. 기초지반은 UBC 분류에서 규정한 보통지반인 Sn 지반과 연약지반인 SE 지반을 고려하였고, 지반의 비선형 특성은 Ramberg-Osgood 모델을 이용하였다. 비선형 지반이 기초지반 수평 및 회전 동적 강성 및 감쇠비에 미치는 영향을 조사하기 위하여 얕은 기초와 묻힌기초에 대해 기초 크기, 지반깊이 및 말뚝유무에 따른 동적 강성 및 감쇠비 변화를 조사하였는데, 지반의 비선형 특성이 기초지반의 선형 수평 및 회전 강성과 감쇠비를 크게 감소 또는 증가시키는 것으로 나타났으며, 기초크기, 지반깊이 및 말뚝유무의 영향도 큰 것으로 나타나 구조물 지진해석시 기초크기, 지반깊이 및 말뚝유무와 함께 지반의 비선형성도 고려하는 것이 필요한 것으로 판단되었다.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.236-243
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• 2005

Nonlinear static analysis is used to quantify the resistance of the structure to lateral deformation and to gauge the mode of deformation and intensity of local demands. A simple method for the nonlinear static analysis of complex building structures subjected to monotonically increasing horizontal loading(pushover analysis) is presented. The method is designed to be a part of new methodologies for the seismic design and evaluation of structures. A variety of existing pushover analysis procedures are currently being consolidated under programs such as ATC 40 and FEMA 273. And various techniques have been recommended, including the use of constant lateral force profiles and the use of adaptive and multimodal approaches. In this paper a modal pushover analysis using design response spectra of UBC 97 is proposed. Proposed method is compared against the method in FEMA 273 and ATC 40, and results of time history analysis.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.10a
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• pp.201-208
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• 1997

In most seismic codes such as the Uniform Building Code(UBC), the response modification factor(or the force reduction factor)is used to reflect the capability of a structure in dissipating energy through inelastic behavior. The response modification factor is assigned according to structural system type. Ductile systems such as special moment-resisting steel frames are assigned larger values of the response modification factor, and are consequently designed for smaller seismic design forces. Therefore, structural damage may occur during a severe earthquake. To ensure safety of the structures, the suitability of the response modification factor used in aseismic design procedures shall be evaluated. The object of this study is to develop a method for the evaluating of the response modification factor. The validity of the evaluating method has been examined for several cases of different structures and different earthquake excitations.

• Journal of the Korean Professional Engineers Association
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• v.28 no.2
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• pp.13-20
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• 1995

This paper Is to help the structural engineers for a better understanding of "Earthquake" with regard to the nature o( earthquake and the effect of earthquake on building structures. This reveals that the damage Inflicted upon by earthquake varies with many factors such as : magnitude of earthquake, distance from epicenter, site conditions, building structural characteristics and etc.. It is emphasized that in order to resist very strong earthquake, the ductility demand in the building structure Is important, and the proper duc-tility enables the structure to demonstrate inelastic rotation capacity of the joints and thus the structure may absorb and dissipate the seismic energy. This also presents a comparison between the current Americal UBC Code and the Korean Code, and the author expresses some points of concern on each code. Since earthquake almost invariably strikes at times and places, it is suggested that the current Korean Build-ing Code should be revised to enforce more stringent regulation against possible strong earthquake in the Korean peninsula.