• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.305-312
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• 1999

A four-story reinforced concrete frame building model is designed for the gravity loads. only Static nonlinear pushover analyses are performed in two orthogonal horizontal directions. The overall capacity curves are converted into ADRS spectra and compared with demand spectra. At several points the deformed shape moment and shear distribution are calculated. It is observed that the seismic capacity may not meet the design requirements in soft soil condition and may collapse in MCE. It is concluded that limited but adequate amount of ductility need be provided in the seismic design in low to moderate seismicity regions.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.370.2-370
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• 1999

• 한국강구조학회 논문집
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• 제18권5호
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• pp.553-562
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• 2006

바람과 지진에 의한 횡력은 고층건물의 설계에 영향을 미치는 주요하중이다. 본 연구에서는 중/약진대로 분류되지만 강한 태풍이 내습하는 국내의 횡하중 환경하에서 철골조 초고층건물의 내진설계의 핵심문제를 취급하고자 하였다. 즉 연성이 아니라 강성과 강도에 의한 탄성 내진설계의 가능성을 타진하기 위해, 내풍설계된 철골조 초고층 중심가새골조의 푸쉬오버해석, 동적 지진응답해석 및 내진성능평가를 수행하였다. 내풍설계에서 요구되는 사용성 요건을 만족시키면 상당한 크기의 시스템 초과강도가 유입됨을 내풍설계의 분석 및 푸시오버해석을 통하여 확인할 수 있었다. 결과적으로 양질로 내풍설계된 세장비 5이상의 철골조 초고층 중심가새골조는 2400년 재래기의 최대고려지진에 대해서도 즉시입주 가능한 거동수준에서 탄성적으로 저항할 수 있음이 확인되었다. 본 연구의 결과를 종합하여 실무설계에서 활용될 수 있는 풍진대에서의 철골조 초고층건물의 탄성내진설계절차 및 관련 권장사항을 제안하였다.

• Structural Engineering and Mechanics
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• 제39권4호
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• pp.559-578
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• 2011

In regions of high seismic risk, high-strength concrete (HSC) columns of tall buildings are designed to be fully ductile during earthquake attack by providing substantial amount of confining steel within the critical region. However. in areas of low to moderate seismic risk, the same provision of confining steel is too conservative because of the reduced seismic demand. More critically, it causes problematic steel congestion in the beam-column joints and column critical region. This will eventually affect the quality of concrete placing owing to blockage. To relieve the problem, the confining steel in the critical region of HSC columns located in low to moderate seismicity regions can be suitably reduced, while maintaining a limited ductility level. Despite the advantage, there are still no guidelines developed for designing limited ductility HSC columns. In this paper, a formula for designing limited ductility HSC columns is presented. The validity of the formula was verified by testing half-scale HSC columns subjected to combined high-axial load and flexure, in which the confining steel was provided as per the proposed formula. From the test results, it is evident that the curvature ductility factors obtained for all these columns were about 10, which is the generally accepted level of limited ductility.

• Earthquakes and Structures
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• 제12권3호
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• pp.375-388
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• 2017

Prior to modern seismic provisions, several bridges were not designed for seismic actions in moderate seismic areas. Precast multi-girder and slab bridges are typical highway overpass structures; they have a significant contribution to national bridge stocks. Since the seismic behavior is questionable, a preliminary parametric study is conducted to determine critical configurations and components. The results indicate that the behavior of the abutments, backfill soil, superstructure and foundation is normally satisfactory; however, the superstructure-abutment joints are critical for both single- and multi-span bridges, while the piers are also critical for longer multi-span configurations. The parametric results provide a solid basis both for detailed seismic assessment and development of design concepts of newly built structures in moderate seismic zones.

• 한국지진공학회논문집
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• 제22권2호
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• pp.77-86
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• 2018

This study develops an empirical prediction equation of spectral acceleration responses of earthquakes which can induce structural damages. Ground motion records representing hazards of low-to-moderate seismic regions were selected and organized with several influential factors affecting the response spectra. The empirical equation and estimator coefficients for acceleration response spectra were then proposed using a robust nonlinear optimization coupled with a regression analysis. For analytical verification of the prediction equation, response spectra used for low-to-moderate seismic regions were estimated and the predicted results were comparatively evaluated with measured response spectra. As a result, the predicted shapes of response spectra can simulate the graphical shapes of measured data with high accuracy and most of predicted results are distributed inside range of correlation of variation (COV) of 30% from perfectly correlated lines.

• Steel and Composite Structures
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• 제18권1호
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• pp.121-134
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• 2015

This paper is to investigate the potentials of the elastic seismic design of twisted high-rise steel diagrid frame buildings in the strong wind and moderate/low seismicity regions. First, the prototypes of high-rise steel diagrid frames with architectural plans that have a twist angle of 0 (regular-shaped), 1, and 2 degrees were designed to resist wind. Then, the effects of the twist angle on the estimated quantities and structural redundancies of the diagrid frames were examined. Second, the seismic performance of the wind-designed prototype buildings under a low seismicity was evaluated. The response spectrum analysis was conducted for the service level earthquake (SLE) having 43-year return period and the maximum considered earthquake (MCE) having 2475-year return period. The evaluation resulted that the twisted high-rise steel diagrid frames resisted the service level earthquake elastically and most of their diagrid members remained elastic even under the maximum considered earthquake.

• Earthquakes and Structures
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• 제10권6호
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• pp.1391-1404
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• 2016

Peninsular Malaysia lying on the stable Sunda Plate has traditionally been considered safe with low to moderate seismicity. However, far field Sumatran mega-earthquakes have been shown to be capable of triggering ground motions felt in high rise structures in the major Malaysian cities while seismic impact from local earthquakes of moment magnitude 3.8 have reportedly induced nominal structural damages to nearby buildings. This paper presents an overview of the recent seismic activities in and around Peninsular Malaysia with reference to prominent earthquakes generated by far field interplate and local intraplate sources. Records of ground motion data and seismic hazard assessment (SHA) results available in the literature have been analyzed and discussed. The peak ground acceleration (PGA) values from historical records for few local intraplate events were observed to be higher than those for the events from Sumatran Subduction Zone. This clearly points to the need for a detailed and comprehensive SHA incorporating both far field and local sources. Such an analysis would contribute the knowledge required for secure and reliable infrastructure design and safeguard the Malaysian people and economy.

• 한국지구과학회지
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• 제32권1호
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• pp.152-157
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• 2011

일본, 중국 등 인접 지진다발 국가에서 큰 지진동이 전파되어 오는 경우, Lg파가 최대 진폭을 갖게 되어 Lg파의 감쇠상수($Q^{-1}$)는 매우 중요한 의미를 갖게 된다. 지진연구협의회(IRIS)의 자료를 바탕으로 관측점간 경로거리가 긴 자료에 대하여 두관측점법을 이용하여 Lg파의 감쇠상수 값을 도출한 결과, 지진활동도에 상응하는 감쇠값을 얻었다. 일본지역을 잇는, 해양지각을 통과하는 경로는 높은 감쇠값을 보여서 지진활동도 및 지각의 감쇠특성을 잘 나타내고 있으며, 또한 큰 지진이 많았던 중국 상해지역을 잇는 경로도 일본지역 다음으로 높은 감쇠값을 보인다. 반면, 한반도 및 만주지역을 잇는 경로는 지진활동상황과 상응하는 매우 낮은 값을 보였다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.178-185
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• 1999

Minimum life-cycle cost helps to evaluate cost effectiveness of base-isolated bridges under specific condition. Life-cycle cost mainly consists of the initial construction cost and the expected damage cost. Damage cost estimation needs proper model of input ground motion failure probability evaluation method and limit states definition. We model the input ground motion as spectral density function compatible with the response spectra defined at each seismicity and site condition. Spectrum analysis and crossing theory is suitable for reseating calculation of failure probabilities in the process of cost minimization. Limit states of base-isolated bridges re defined for superstructure isolator and pier respectively The method is applied to both base-isolated bridges and conventional bridges under the same conditions to investigate cost effectiveness of base isolation in low and moderate seismic region. the results show that base-isolation of bridges are more effective in low and moderate seismic region and that the site effects on the economical efficiency may not be negligible in such a region.