• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.241-244
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• 2008

The authors proposed a new rapid-screening method for more reasonably evaluating seismic capacities of medium and low-rise RC buildings controlled by both shear and flexure in Ref. [1]. The method proposed in Ref. [1] was based on relationships between required strengths of each failure system for ductility factors and damage degrees of overall system derived from the view-point of ductility factors. The proposed method was also verified using observed real damage data of low-rise RC buildings caused by past earthquakes. Results indicated that the methodology proposed in Ref. [1] compares well with real damages and is a useful strategy for rapidly identifying low-rise RC buildings having high potential seismic risk. In this study, in order to verify the applicability of the new methodology proposed in Ref. [1] to real RC building systems, seismic capacities of existing eleven low-rise RC buildings in Korea are evaluated based on the new method.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.13 no.1
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• pp.63-74
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• 2000

The main objective of this paper is to apply as the basic data for development of a methodology to discuss the future earthquake preparedness measures in Korea by investigating the concept and applicabilities of the Japanese Standard for Evaluation of Seismic Performance of Existing RC Buildings developed in Japan among the methodologies of all the countries of the world. This paper describes the seismic performance, Is-index, of existing RC buildings in Tokyo, Japan evaluated by the Japanese Standard, also the relationships between Is-index distribution of existing RC buildings in Tokyo and that of Shizuoka and Chiba Prefecture reported already in reference[4][5][6] are investigated. And from the comparison with Is-index to buildings damaged by earthquakes experienced in Japan, the damage ratio due to severe earthquake of 3 districts mentioned above is estimated based on the probabilistic point of view. The results of this study can be utilized to identify urgently required earthquake preparedness measures with highest priority in existing RC buildings, and the methodology to evaluate the seismic performance of existing RC buildings in Japan, statistics analysis method and the methodology to estimate earthquake damage ratio based on the probabilistic point of view shown in this study can be recommended to develop a methodology to discuss the future earthquake preparedness measures in Korea.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.5
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• pp.41-50
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• 2009

Following an earthquake, the major concerns for damaged buildings are their safety/risk in the event of aftershocks, and thus a quantitative damage assessment must be performed in order to evaluate their residual seismic capacity and to identify necessary actions for the damaged buildings. Post-event damage evaluation is therefore as essential for the quick recovery of a damaged community as pre-event seismic evaluation and strengthening of vulnerable buildings. The objective of this study is to develop a post-earthquake seismic evaluation method for RC frames with URM infill wall for typical school buildings. For this purpose, full-scale, one-bay, single-story specimens having different axial loads in columns are tested under cyclic loadings. During the tests, residual crack widths, which can also be found in damaged buildings, are measured in order to estimate the residual seismic capacity from the observed damage. In this paper, the relationship between the measured residual crack width and the residual seismic capacity is discussed analytically and experimentally, and reduction factors are proposed to estimate the residual seismic capacity based on the observed damage level.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.73-76
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• 2008

According to the survey of earthquake disaster, low-rise reinforced concrete building larger by the extent of damage and because of the underlying distribution of reinforced concrete structures more, it is very likely to be disasters. The purpose of this study is to discuss how strength and stiffness of each system in low-rise reinforced concrete buildings consisted of extremely brittle, shear and flexural failure lateral-load resisting systems have influence on seismic capacities of the overall system. Generally, if shear failure members including extremely brittle failure members are failed during an earthquake, the lateral-load resisting seismic capacities of RC buildings are lower rapidly, and if the seismic capacities of shear failure members were higher than that of flexural failure members, failures of shear failure members have influence on failures of the overall system. The result of this paper will provide pseudo-dynamic test of carried out to estimate the possibility of proposals.

• Computational Structural Engineering
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• v.10 no.1
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• pp.62-69
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• 1997

본 고에서는 고층건물의 건설과정에서 발생하는 시간의 진행에 따른 기둥의 (장기)변형을 정확히 예측하고 이를 시공중에 보정하도록 함으로써 비구조요소의 강도와 사용을 만족시키기 위한 방법론을 제시하였다. 이 방법론은 실험적 통계치를 기초로 한 약산해법으로서 실무에 쉽게 적용할 수 있다. 52층 RC 건물에 대한 적용 결과 기둥에 발생하는 축소량에 가장 큰 영향을 미치는 것은 탄성변형이며, 건조수축의 효과가 가장 미세한 것으로 나타났다. 그러나, 2년 이상의 장기 변형이 지속될 경우 크립변형의 영향이 탄성변형에 비해 더욱 증가할 것으로 판단된다. 고층의 RC건물인 경우 기둥간 부등축소량의 최대치(=최대 시공오차)는 중간층 근처에서 발생하는 것으로 나타났다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.103-111
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• 2008

The purpose of this study is to find the way to determine the thickness of RC shear wall outriggers of tall buildings. For this, the analysis models of tall buildings with 60 stories are generated and analyzed. Then the changes of load transfer and deformation caused by the outriggers are investigated and the equation for the determination of the thickness of RC shear wall outriggers is proposed. Finally, the proposed equation is verified for the variously modified analysis models.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.3
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• pp.106-115
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• 2011

This study proposed a new methodology for seismic capacity evaluation of low-rise reinforced concrete (RC) buildings based on non-linear required spectrum. In order to verify the reliability of the proposed method, relationships between results obtained using the proposed method and the non-linear dynamic analyses were investigated. Compared with the seismic protection index (Es=0.6) defined in the Japanese Standard, the applicability of the method was also estimated. Research results indicate that the method proposed in this study compares reasonably well with the detailed evaluation methods. Using the seismic evaluation method developed in this study, the seismic capacity category and earthquake damage degree of low-rise RC buildings corresponding to a specific earthquake level can be effectively estimated.

• Journal of the Korea Concrete Institute
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• v.17 no.5 s.89
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• pp.727-734
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• 2005

High-rise residential buildings these days tend to adopt a building frame system as primary earthquake resisting structural system for some architectural reasons. But there exist several ambiguities in designing such building frame systems according to current codes with regards to : the effective stiffness property of RC cracked section in static and dynamic analyses, analytical model to evaluate story drift ratio, and deformation compatibility requirements of frames. The comparative study for these issues by appling KBC 2005 to a typical building frame system shows that demands of member strength and story drift ratio can be different significantly depending on engineer's Interpretation and application of code requirements. And a building frame system can be noneconomical, compared with the dual system, because of higher demands on strength or ductility in both frames and shear walls.

• Land and Housing Review
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• v.5 no.2
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• pp.107-114
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• 2014

Passive energy dissipation systems for seismic applications have been under development for a number of years with a rapid increase in implementations starting in the mid-1990s in many countries. A metallic hysteretic damper has most commonly been used for seismic protection of structures in domestic area because they present high energy-dissipation potential at relatively low cost and easy to install and maintain. This paper presents an analytical case study of the effectiveness of isotropic hysteretic metallic damper(IHMD) called Kagome as a passive dissipative device in reducing structural response during seismic excitation. An eighteen-story RC framed apartment building is studied with and without IHMD. Results demonstrate the feasibility of these techniques for seismic mitigation. The inclusion of supplemental passive energy dissipation devices in the form of IHMD proved to be a very effective method for significantly reducing the seismic response of the building investigated.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.307-315
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• 1994

The object of this experiment was to suggest the suitahle N-P-K fertilization level for orchardgrass(0G)-red clover(RC) mixtures under the intensive system of short-term pasture utilization. The fields trials were conducted over 3-year period(1991-1993) to evaluate dry matter yield. botanical composition, chemical composition and CP, DDM yield on the N-P-K levels (0-0-0. 50-100-100. 100-150-150, 150-2OO-200. 200-250-250 and 300-350- 350kg/ha). With increasing level of N-P-K, the DM yield of OG in the OG-RC mixture were significantly increased(P< 0.05), however, that of RC was remarkably decrcawd(P