• Earthquakes and Structures
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• 제25권1호
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• pp.1-13
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• 2023

Reinforced concrete (RC) moment frames are used as lateral seismic load resisting systems in mid- and high-rise buildings in different regions of the world. Based on the seismic design provisions and construction details presented in design codes, RC frames with different levels of ductility (ordinary, intermediate, and special) can be designed and constructed. In Iran, there are RC buildings with various uses which have been constructed based on different editions of design codes. The seismic performance of RC structures (particularly moment frames) in real seismic events is of great importance. In this paper, the observations made on damaged RC moment frames after the destructive Sarpol-e Zahab earthquake with a moment magnitude of 7.3 are reported. Different levels of damage from the development of cracks in the structural and non-structural elements to the total collapse of buildings were observed. Furthermore, undesirable failure modes which are not expected in ductile seismic-resistant buildings were frequently observed in the damaged buildings. The RC moment frames built based on the previous editions of the design codes showed partial or total collapse in this seismic event. The extensive destruction of RC moment frames compared with the other structural systems (such as braced steel frames and confined masonry buildings) was attributed not only to the deficiencies in the construction practice of these buildings but also to the design procedure. In addition, the failure and collapse of masonry infills in RC moment frames were frequent modes of failure in this seismic event. In this paper, the main reasons related to design practice which led to extensive damage in the RC moment frames and their collapse are addressed.

• 한국건설관리학회논문집
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• 제21권6호
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• pp.66-74
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• 2020

해체공사의 수요증가와 사고 위험성을 고려하여 정부는 20년 건축물관리법을 시행해 해체공사의 안전관리를 개선하고자 하였다. 그러나 건축물관리법 제 30조 건축물의 해체 허가에 따른 기준은 일률적이기 때문에 규모에 따른 허가대상 건축물의 구분은 불합리할 수 있다. 또한, 해체공사는 건축물의 구조 유형에 따라 공사 난이도 및 발생 재해의 형태가 달라질 수 있기 때문에 본 연구는 건축물관리법상 신고대상에 속하는 조적조 등의 소규모 건축물의 구조 유형을 고려한 해체공사 안전관리 개선 방안을 제시하고자 한다. 본 연구의 순서는 (I) 건축물관리법 기준; (II) 건축물의 구조 유형에 따른 해체공사 분석; (III) 해체공사 허가대상 세분화 순으로 진행되었다. 연구 결과 건축물관리법상 허가대상은 과거 해체공사 실적의 10% 정도, 조적조는 2.43%에 불과하였다. 허가대상 기준을 세분화한 결과 조적조의 경우 연면적 100㎡이하일 때 허가 및 신고대상의 수가 유사해짐을 확인하였다. 이를 통해 이해관계자는 1) 해외와 같이 규모에 관계없이 특수구조 건축물에 강화된 안전관리 기준을 적용하거나, 2) 건축물의 구조 유형에 따라 해체공사 허가 대상 기준을 세분화하는 방식 등을 활용한 해체공사 안전관리를 개선할 수 있다.

• 농업과학연구
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• 제38권1호
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• pp.101-108
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• 2011

In forest work, working conditions are very hard to improve. The proper distribution of work time and good posture is believed to bring about direct improvements such as accident prevention. On this, this study has analyzed forest workers' posture and their working hours in order to improve their working conditions in stone channel work. Authors has chosen several core elements of stone channel work to focus on, which include stone masonry, excavation of bed, moving stone, directing work, choosing stone, and breaking stone. The ratio of real working time over total working time was shown as 84.6%. As for the time ratio of each elemental work over the real working time, the stone masonry was 60.4%, the directing work was 15.1%, moving stone was 12.1%, choosing stone was 7.1%, breaking stone was 3.3%, and excavation of bed was 2.0%. According to the analytical results provided by OWAS, the ratio of category III (Work posture has a distinctly harmful effect on the musculoskeletal system) has shown that moving stone turned out 65.2%, choosing stone was 61.5%, stone masonry was 46.1%, breaking stone was 14.3%, excavation of bed was 12.5% and directing work was 6.8%. Furthermore, the ratio of category IV (Work posture with an extremely harmful effect on the musculoskeletal system) has shown that excavation of bed turned out 37.5%, breaking stone was 28.6%, stone masonry was 27.3%, choosing stone was 7.7%, moving stone was 6.1% and directing working was 4.5%. These results are expected to be utilized for the improvement with respect to both working methods in the stone channel work and the workers' working posture.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.37-43
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• 2020

국내 도로, 철도 등 SOC 시설의 내진보강율은 2017년 기준 96%이며 건축물은 2016년 기준 약 7백만동 중 내진성능이 확보된 건축물은 51만동에 불과하다. 조적조 건축물은 전체 건축물의 38.8%를 차지할 만큼 비중이 크지만 내진성능이 확보된 것은 2.0% 내외로 거의 전무한 실정이다. 이러한 문제를 해결 하기 위해국내에서는 정부차원의 내진 대책이 추진되고 있으나 현재까지 미비한 상황이다. 국외의 캐나다 벤쿠버 UBC 연구팀은 조적조 내진성능 보강을 위해 EDCC를 개발하여 사용하고 있다. EDCC는 섬유혼입으로 콘크리트 연성능력 확보 및 가교작용으로 콘크리트의 변형 저항능력을 확보 할 수 있는 건설재료이다. 그러나 내진성능 확보를 위해 EDCC를 분사형으로 사용하지 않기 때문에 다양한 재료의 검토가 필요하다. 이에 본 연구에서는 조적조의 내구성능 향상을 위한 뿜칠재료 연구개발의 일환으로 내진보강용 섬유보강 모르타르의 분사특성을 평가하고자 하였으며, 섬유보강 모르타르의 섬유사용량에 따른 분사특성 및 증점제 사용량에 따른 점도변화를 검토하였다. 조적조 내진보강용 섬유보강 모르타르의 부착성능 및 시공성능을 검토한 결과 섬유의 사용량은 1%, 증점제의 사용량은 1%로 최적 사용량을 도출할 수 있었다.

• 한국공간구조학회논문집
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• 제15권3호
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• pp.69-76
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• 2015

Cheomseongdae is the masonry stone structure with the cultural and historical values. But, this structure has the various damages such as cracks, gaps, slope variations and ground subsidence. So, the interests for the safety security in the structural parts have been increased. Therefore, this study performs the structural modelling which considers the several damage cases, and then evaluates the structural behavior characteristics through the discrete element analysis. Especially, this study checks the swelling and displacement gap of the whole structure and the separation between the neighboring members.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.103-105
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• 2011

The purpose of this study is to suggest basic data which is firing technique at manufacturing time for preservation and rehabilitation of masonry modern architecture by assumed firing-temperature. It could be possible to estimate firing-temperature at manufacturing time through the result of the experiments, XRD and changed absorbing ratio from re-firing.

• 한국소음진동공학회논문집
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• 제23권11호
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• pp.987-995
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• 2013

One of the most important processes to accurately predict structural responses is to evaluate accurate structural dynamic characteristics using finite element(FE) models. The numerical structural dynamic characteristics usually show considerable discrepancies with the measured ones because structural details are commonly simplified in the FE models. To identify such discrepancies, FE models of them have been calibrated using the measured dynamic characteristics in previous researches. In this study, the dynamic characteristics were measured for a historic cathedral and the FE model of it was calibrated using the measured results as a reference. Finally, a procedure of the FE model construction for the unreinforced masonry cathedral were tentatively proposed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.117-121
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• 2006

This study intends to suggest the effective methods for water leakage prevention around the windows in stone works to up-grade the outdoor public space that has been taken much portion of apartment housing trends. The subjects of the study was selected among the domestic subcontractors of stone works. There are four methods for water leakage prevention around the windows; Firstly, the painting water-proof method after the masonry. Secondly, the urethane water-proof method after galvanizing panels on the gap. Thirdly, the separation method between stone and substructure and the last one is water-proof method that they put some water-proof screen between stone and substructure with the EPDM sheets. According to the analysis of the water-proof effects, constructability and planning, we could approach to conclusion that the most influent items to the water-leakage are the filling material's deformation, the state of oxygenation and deterioration of work skill. Among the water-proof methods in construction the EPDM sheet is most excellent water-proof method to meet the technical conditions. However, we have to apply it to stone works as a water-proof method for the decrease of the leakage defects after standardizing the materials, test and construction skill because there are many work skills according the subcontractors.

• 한국건축시공학회지
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• 제9권2호
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• pp.93-101
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• 2009

Recently, public interest in housing defects, such as construction errors, occupiers' complaints, faults in production, and so on, is increasing. In addition, the construction requirements of high-rise residential buildings have increased, due to the higher prices of urban areas, especially in metropolitan areas. While previous research has focused on the defects occurring in apartment housing complexes, research has not been carried out on the defects occurring in high-rise residential buildings. In this paper, the defects patterns and characteristics of high-rise residential buildings are examined and analyzed and a defect management plan is then suggested. In order to do this, we collected the defects data of high-rise residential buildings recorded by 2,299 of 2,327 occupants. The defect occurrence rate (DOR) in the residential area is 98.8%. The frequency rate of defect occurrence over the total defect occurrence since building completion is 63.28% during the first year, 24.63% (second year), 6.88% (third year), 2.27% (fourth year), and 2.53% (fifth year). The result of correlation analysis between work types showed that there is a relationship between the built-in furniture and electronics (F&E) and painting works, and the F&E and masonry works, such as marble finishing. We expect that this research will assist in the efforts to decrease the number of defects in high-rise buildings.

• 한국건축시공학회지
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• 제21권6호
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• pp.641-652
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• 2021

화성성역의궤에는 화성성역에 대한 상세정보가 기록되어 있으나, 현대적 건설관리 관점에서 분석과 평가는 제한적으로 진행되었다. 이에 본 연구에서는 팔달문을 대상으로 하여 시간, 비용, 인력 등 건설관리 관련 정보를 분석하였다. 팔달문 건설에 주요공종은 기초공사와 석공사였고, 전체 공기는 6개월로 전체적으로 매우 빠르게 공사가 진행되었다. 팔달문 건설의 소요비용의 총합은 약 52,423냥인데, 자재비에 약 15,9332냥이 소요되고, 인건비에는 약 36,4901냥이 소요되었다. 이를 현재가치로 환산하면, 자재비 약 11억원, 인건비 약 25억원으로 합은 약 36억원 수준이다. 향후에 공종별 작업 기간과 연계된 상세 투입인력 도출 등 추가적인 연구를 진행할 예정이다.