• Journal of Korean Association for Spatial Structures
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• v.22 no.3
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• pp.57-64
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• 2022

As earthquakes have increased in Korea recently, people are paying attention to the seismic performance of buildings built in the past. Many school buildings in Korea were built based on standard drawings before the seismic design was applied. However, since school buildings are often designated as emergency evacuation facilities in case of disasters such as earthquakes, seismic evaluation and retrofit must be done quickly. This study investigated the failure modes among structural components (beams, columns, and joints), focusing on 1980s standard drawings for school buildings. The effects of column axial force, partial masonry infills, and different material strengths for concrete and rebar were considered for detailed evaluation. As a result, most of the joints were found to be the weakest among structural components. Column axial forces tended to make the joints more vulnerable, and partial masonry infills increased the possibility of joint failure and shear failure in columns.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.259-266
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• 2011

The transient vibration test and synchronized human excitation is performed for low-rise concrete buildings and their identified natural frequency, damping ratio, and mode shape are compared. Form the identified dynamic parameters, it was found that the damping ratio obtained through the synchronized human excitation test is greater than those obtained from the transient vibration test. However, the mode shapes of the first mode are not significantly different regardless of the test method. Further, the stiffness of the interior brick partition considerably affect the stiffness of the entire building such that the first natural mode of rectangular shaped building occurred in the longitudinal direction rather than transverse direction.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.4
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• pp.1-10
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• 2004

The purpose of this study is to investigate the flexural behavior of square concrete filled carbon tube (CFCT) columns subjected to constant axial load with the cyclic lateral load. Two parameters, wnding angle and thickness of tube, were chosen to evaluate the flexural capacity and behavior of rectangular CFCT columns. Selected two parameters were considered simultaneously in order to evaluate the flexural behavior of a rectangular CFCT columns more precisely. Flexural strength, deformation capacity, ductility and energy dissipation capacity of rectangular CFCT columns were evaluated by calculating the area of load-displacement envelope curves and load-dispalcement hysteresis curves obtained from experiment. Also, the ductile capacity obtained from experiment was compared to that of reinforced masonry wall for the comparison of existing structural element.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.157-161
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• 1994

To investigate the morphology of Bacillus thuringiensis crystal proteins, two type crystal protein genes, cryIA(c) gene under the control of cryIA(b) gene promoter and cryIIA gene under the control of its own promoter, were transformed in B. thuringiensis acrystalliferous mutant strain and the transformants were characterized by SDS-PAGE and scanning electron microscopy. The expression and formation of crystal proteins in B. thuringiensis subsp. kurstaki Cry-B revealed that crystal proteins appear to have same molecular weight and morphology to those of wild type strain's, suggesting that the expression and formation of crystal proteins affected not by host cell or recombination of cryIA(e) gene under the control of cryIA(b) gene promoter but by only structural fragment of protoxin.

• The Journal of the Petrological Society of Korea
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• v.8 no.2
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• pp.81-91
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• 1999

The area of the study is located in Ogcheon district, middle part of Ogcheon Fold Belt. The area is covered by metasedimentary rocks of Ogcheon Supergroup at northern, eastern and southern part. Jurassic Ogcheon granite which intruded into Ogcheon Supergroup at central part, was intruded by Cretaceous quartz porphyry at western part. The granite consists of quartz, plagioclase, alkali feldspar, biotite, sphene, apatite, epidote, opaque and so on. It is generally characterized by grey to light grey, medium-grained, mafic enclave and partly weak foliation. In terms of geochmical compositions, the granite is felsic, peraluminous, subalkaline and calc-alkaline, and it was differentiated from single granitic magma. It shows parallel LREE enrichment and HREE depletion patterns with 0.84 Eu negative anomaly, which has REE variation trend and anomaly value similar to Jurassic granites in Korea. From charactristics of petrology, mineralogy and geochmistry, it may be interpreted that the Ogcheon granite body was derived from melting of I-type crustal material related to syn-collisional tectonic setting and emplaced more or less rapidly into the Ogcheon Supergroup.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.198-209
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• 2006

일본적전대삼희(日本的田代三喜)(たしろさんき)재명류학후(在明留學后), 타회도일본적시후(他回到日本的時候), 종명수입(從明輸入)'이주의학(李朱醫學)'. 연후충파(然后衝破)${\ulcorner}$화제국방${\lrcorner}$, 용음양 허실(虛實) 기혈(氣血) 한열등제창료변증시치적신방법(寒熱等提倡了辯證施治的新方法). 타적도제곡환뢰도삼(他的徒弟曲宦瀨道三)(まなせどうさん)건립(建立)'거적원(居迪院)', 이보급료당시최신수평적의학(以普及了當時最新水平的醫學). 타문의거적시금(他們依据的是金) 원(元) 명시대의학(明時代醫學), 소이타문규주(所以他們叫做)'후세파(后世派)'. 이후순착복고사조적흥기(以后順着複古思潮的興起), 일본의학계야주장료척시(日本醫學系也主張了隻是)${\ulcorner}$상한론(傷寒論)${\lrcorner}$적완전사용(的完全使用), 이반대료음양오행 장부경맥적학설.유차출현료향송명의학게간이기적(由此出現了向宋明醫學揭竿而起的)'고방파(古方派)'화접수량가우점적(和接受兩家優点的)'절충파(折衷派)'. 유료중시문헌연구적(有了重視文獻硏究的)'고증파(考證派)', 유료(有了)'후세별파(后世別派)' ; 인(因)'후세파(后世派)'중류완소(中劉完素) 장종정비리고 주진형경중시이흔양방. 환유료령두접수서방의학적(還有了領頭接受西方醫學的)'한란절충파(漢蘭折衷派)'등(等). 본연구(本硏究), 향일본의학방면상의대야기리론적쟁변(向日本醫學方面上擬待惹起理論的爭辯). 고찰대(考察對)'고방파(古方派)'상대적(相對的)'후세파(后世派)', 이능료해일본한방적의학특점(以能了解日本漢方的醫學特点). 소이본론자연구병보고(所以本論者硏究幷報告) ; 규주(叫做)'후세파(后世派)'적래룡거맥, 학술요지(學術要旨), 역사적지위(歷史的地位), 지류별파적형성배경이급창시병흥복(支流別派的形成背景以及倡始幷興復)'후세파(后世派)'적대표의가(的代表醫家)'전대삼희(田代三喜)'화타도제곡직뢰도삼적생애(和他徒弟曲直瀨道三的生涯), 착작급학술특점(着作及學術特点).

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.29-29
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• 2011

국내에서 기존건축물의 내진성능평가 기법이 연구되기 시작한지 20여 년간 다양한 평가방법이 제안되었다. 그러나, 제안된 평가방법은 미국이나 일본의 평가 방법을 도입 및 수정하는 내용이 주가 되어 국내실정에 맞지 않는 부분도 많이 발견되었다. 따라서 국내에서 제안된 기존 건축물의 내진성능 평가기법, 지진피해예측에 근거한 보강건축물의 합리적인 선정방법 및 이들 건축물에 적합한 내진보강방법 등의 연구는 아직까지 초보적인 단계라고 할 수 있다. 이에 본 연구의 목적은 이러한 평가 기법을 적용한 국내 저층구조물의 내진성능을 평가하는 것이다. 저층구조물의 내진성능을 평가하기 위하여 1988년 내진설계가 도입되기 이전에 건립된 4층 규모의 학교구조물을 해석대상 구조물로 선정하였다. 대상 해석구조물의 내진성능평가는 일본의 내진성능 평가법을 참고하여 평가절차가 다소 복잡한 부분을 국내 실정에 맞게 개선시킨 내진화 우선도 평가방법과 정밀한 내진성능을 평하는 방법으로 세계적으로 널리 사용되고 있는 ATC-40 성능평가방법에서 등가단자유 모델로 변환 과정에서 등가유효감쇠 및 등가유효주기 산정 관계식의 문제점을 개선한 FEMA-440의 선형화 성능평가방법(Linearization Method)을 사용하여 구조물의 성능을 평가하였다. 내진 성능 평가를 위해 현재 전 세계적으로 널리 사용되고 있는 구조물 비선형 전용 해석 프로그램인 Perform-3D를 이용하여 해석을 수행하였다. 본 연구를 통해 기존 저층구조물로 선정한 학교구조물에 대한 내진성능을 평가한 결과, 내진화 우선도 평가법 및 FEMA-440의 내진성능 평가는 유사한 경향의 결과를 나타내었고, 두 평가결과를 요약하면 Y방향은 보와 기둥에 끼인 조적벽체의 영향으로 별도의 내진성능이 향상 보강이 필요없으나, X방향은 창문하부 허리 조적벽 등의 영향으로 다소 취성적인 내진성능을 보유하고 있어 충분한 내진성능 확보를 위한 추가적인 보강이 필요한 것으로 판단된다.

• Journal of the Korea Institute of Building Construction
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• v.10 no.3
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• pp.83-90
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• 2010

The carbon dioxide($CO_2$) emissions that result from construction are one of the main factors causing a global warming problem. It is therefore necessary to make efforts to reduce $CO_2$ emissions in the construction industry. Some researchers have studied $CO_2$ emissions in the industry ; however, there has been a lack of study on $CO_2$ emissions cost. Therefore, in this study, the construction costs, including the $CO_2$ emission cost, of masonry wall type, which is a common brick wall, concrete brick wall, and fired brick wall, were examined. The purpose of this study is to compare the construction costs of masonry wall types, including $CO_2$ emission costs. The study found that the $CO_2$ emission costs were highest for the fired brick wall, followed by the concrete brick wall. This research could provide basic information that can be used in other engineering methods to convert $CO_2$ emissions to $CO_2$ emission cost.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.3
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• pp.83-92
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• 2016

The purpose of this study is to evaluate the seismic performance of domestic unreinforced masonry(URM) buildings using nonlinear dynamic analysis. For that, the nonlinear hysteresis models suggested in the previous research were validated for the dynamic analysis. The results of the shaking table test were compared with the dynamic analysis results using the suggested nonlinear hysteresis models. As a result, the nonlinear hysteresis models were expected to be applicable to the dynamic analysis of URM buildings. Based on the models, the dynamic analysis of domestic URM buildings varying the number of stories and opening ratio was carried out. The analysis results showed that most of the domestic URM buildings were very vulnerable to design earthquake in Korea.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.113-121
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• 2015

Building using masonry accounts for most of the smaller houses in Korea but due to brittle behavior and low ductility the frequency of usage has decreased in recent years. Despite this, this form of building has been gaining attention overseas for its low cost in construction and environment-friendliness of the materials. As such, many studies are being conducted to resolve the disadvantages in structure. This study produced an specimen for masonry-filled wall and the intersection to confirm the difference in structural movement depends on the existence or lack of expansion joint and verified the reinforcement effect from inserting a connecting steel item (steel plate, stainless steel twist bar). The experiment results show that the specimen with a steel plate inserted saw an increase in durability and an improvement in the strength of the specimens, while the specimen that had stainless steel twists bar inserted saw an increase in ductility that did not cause brittle failure, indicating that the reinforcement effects of inserting a connecting steel item are effective.