• Structural Engineering and Mechanics
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• 제60권5호
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• pp.749-760
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• 2016

The objective of the study is to investigate the effects of model calibration on seismic behaviour of a historical mosque which is one of the most significant Ottomon structures. Seismic analyses of calibrated and noncalibrated numeric models were carried out by using acceleration records of Kocaeli earthquake in 1999. In numerical analysis, existing crack zones on real structure was investigated in detail. As a result of analyses, maximum stresses and displacements of calibrated and noncalibrated numerical models were compared each other. Consequently, seismic behaviour and damage state of historical masonry Hafsa Sultan mosque was determined as more realistic in the event of a severe earthquake.

• Earthquakes and Structures
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• 제10권6호
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• pp.1347-1367
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• 2016

The purpose of this work is to investigate the seismic behavior of St. Titus Church in Heraklion, Crete, Greece as well as the need of its seismic retrofitting. A numerical model of the Church is constructed using shell finite elements and it is then seismically examined using response spectrum and linear time-history analyses. Effects of soil-structure interaction have been also taken into account. The Church without retrofit is expected to exhibit extensive tensile failures and many compressive ones. Aiming to maintain the architectural character of the structure as well as to increase its seismic resistance, a retrofitting procedure involving injection of cement grout in conjunction with reinforced concrete jacketing to the internal side of the masonry walls is proposed. A numerical implementation of the proposed seismic retrofitting is performed and its effect is evaluated by response spectrum and linear time-history analyses. From the results of these analyses, it is shown that compressive failures are eliminated while only few tensile failures of local character take place.

• 한국구조물진단유지관리공학회 논문집
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• 제15권4호
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• pp.87-98
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• 2011

최근 생태 친환경 건축이 화두로 등장하면서 친환경 건축재료인 점토벽돌과 공기의 흐름과 수분의 이동이 가능한 석회모르타르의 사용이 증가하고 있다. 하지만 국내 연구는 콘크리트벽돌과 시멘트모르타르에 집중되고 있어 점토벽돌 및 석회모르타르에 대한 연구가 거의 없는 실정이며, 조적조의 국내 기준 또한 국내에서 사용되는 재료와 다른 물리적 값을 사용하고 있는 국외기준을 바탕으로 제정되어 국내 실정을 적절히 반영하지 못하고 있다. 따라서 본 연구는 프리즘압축강도, 부착강도, 전단 및 사인 장강도 실험을 통해 점토벽돌과 석회모르타르를 사용한 조적구조의 물리적 특성을 파악하고자 한다. 또한, 콘크리트벽돌과 시멘트모르타르를 사용한 조적구조와의 물리적 특성을 비교분석하여 국내 조적기준을 개정하기 위한 근거를 제시하고자 한다. 점토 벽돌과 석회모르타르를 적용한 조적구조는 콘크리트벽돌과 시멘트모르타르를 사용한 조적구조와는 다른 양상을 보이므로 점토벽돌과 석회모르타르를 적용한 조적구조의 프리즘압축강도와 탄성계수에 대한 추정식을 제안한다.

• 콘크리트학회논문집
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• 제24권3호
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• pp.305-313
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• 2012

비보강 조적조 건축물은 전세계적으로 기존의 건물 및 역사 건축물의 많은 부분을 차지하고 있다. 특히, 최근 지진이 전세계적으로 빈번하게 나타남에 따라 비보강 조적조 구조물에 대한 내진 보강 대책이 요구되고 있다. 현재 비보강 조적조의 보강방법으로는 숏크리트, ECC jacketing, FRPs(fiber reinforced polymer sheet) 등이 개발되어 사용되고 있다. 특히 많은 엔지니어들이 FRPs를 사용한 보강방법을 채택하는 경향이 보이는데 이는 숏크리트나 ECC jacketing과는 달리 벽체의 두께 확장에 따른 구조물 자중 증가 문제없이 비보강 조적조의 전단강도를 향상시킬 수 있기 때문이다. 그러나 비보강 조적 벽체의 복잡한 역학적 거동과 FRPs를 사용한 실험 데이터의 부족은 아직까지도 적절한 보강량을 산정하는데 어려움을 주고 있다. 이 연구는 비보강 조적조의 면내 거동을 확인하고 두 가지의 다른 특징을 가진 FRPs를 사용한 보강 효과에 대한 정보를 주기 위해 수행되었다. 실험체는 1970년대 한국에서 빈번하게 지어진 저층형 연립주택의 내벽을 대상으로 하고 있으며 별도의 내진 설계는 되어있지 않은 상태이다. 실험체의 형상비는 실제 상황을 반영하기 위해 1에 가깝게 설정되어 있다. 보강 재료로는 탄소섬유보강 시트와 하이브리드 시트를 사용하였으며 이들은 각각 다른 극한 강도와 탄성계수 및 극한 변형률을 보유하고 있다. 연구 결과 비보강 조적 벽체의 면내 전단력 저항 성능을 확인하였으며 FRPs가 사용된 내진 보강 방안의 특성을 분석할 수 있었다. 또한 FRPs를 사용한 보의 전단보강 방법에 착안하여 비보강 조적조에 대한 FRPs의 보강 설계안을 도출할 수 있었다.

• Earthquakes and Structures
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• 제1권4호
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• pp.371-390
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• 2010

Historical buildings in seismically active regions are severely damaged by earthquakes, since they certainly were not designed by the original builders to withstand seismic effects. In particular the reports after major ground motions indicate that earthquake-induced pounding between buildings may lead to substantial damage or even collapse of colliding structures. The research on structural pounding during earthquakes has been recently much advanced, although most of the studies are conducted on simplified single degree of freedom systems. In this paper a detailed pounding-involved response analysis of three adjacent structures is performed, concerning the main bodies of the "Quinto Orazio Flacco" school. The construction includes a main masonry building, with an M-shaped plan, and a reinforced concrete building, separated from the masonry one and realized along its free perimeter. By the analysis of the capacity curves obtained by suitable pushover procedures performed separately for each building, it emerges that masonry and reinforced concrete buildings are vulnerable to earthquake-induced structural pounding in the longitudinal direction. In particular, due to the geometric configuration of the school, a special case of impact between the reinforced concrete structure and two parts of the masonry building occurs. In order to evaluate the pounding-involved response of three adjacent structures, in this paper a numerical procedure is proposed, programmed using MATLAB software. Both a non-linear viscoelastic model to simulate impact and an elastic-perfectly plastic approximation of the storey shear force-drift relation are assumed, differently from many commercial softwares which admit just one non-linearity.

• Geomechanics and Engineering
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• 제18권2호
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• pp.141-151
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• 2019

In this paper, it is aimed to present a detail investigation about the comparison of static and dynamic behavior of historical masonry arch bridges considering different arch curvature. $G{\ddot{o}}derni$ historical masonry two-span arch bridge which is located in Kulp town, Diyarbakir, Turkey is selected as a numerical application. The bridge takes part in bowless bridge group and built in large measures than the others. The restoration projects were approved and rehabilitation studies have still continued. Finite element model of the bridge is constituted with special software to determine the static and dynamic behavior. To demonstrate the arch curvature effect, the finite element model are reconstructed considering different arch curvature between 2.86 m-3.76 m for first arch and 2.64 m-3.54 m for second arch with the increment of 0.10 m, respectively. Dead and live vehicle loads are taken into account during static analyses. 1999 Kocaeli earthquake ground motion record is considered for time history analyses. The maximum displacements, principal stresses and elastic strains are compared with each other using contour diagrams. It is seen that the arch curvature has more influence on the structural response of historical masonry arch bridges. At the end of the study, it is seen that with the increasing of the arch heights, the maximum displacements, minimum principal stresses and minimum elastic strains have a decreasing trend in all analyses, in addition maximum principal stresses and maximum elastic strains have unchanging trend up to optimum geometry.

• 한국공간구조학회지
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• 제10권4호
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• pp.23-30
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• 2010

• 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.

• Earthquakes and Structures
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• 제18권3호
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• pp.321-335
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• 2020

The aim of the present contribution is to consider and underline the essential interactions among the historical knowledge, the seismic vulnerability assessment, the investigation experimental tools, the preservation of the architectural quality and the strengthening design in regard to architectural heritage conservation. These topics are argued in relation to Palazzo Murena in Perugia, designed in the eighteenth century by the famous Architect Luigi Vanvitelli, and currently headquarters of the city's University. Based on the surveys and the visual inspections, a preliminary a priori global analysis has been performed by means of the FME method. The obtained results permitted to plan an experimental tests campaign inclusive of structural health monitoring. The new achieved "knowledge" of the building allowed to refine the seismic safety assessment. In particular it was highlighted that the "mezzanine floor" can be a vulnerable element of the building with the collapse of its masonry walls. Preserving the architectural characteristics, a local reinforcement intervention is proposed for the above-mentioned level; this consists of the application of plaster with FRCM, assuring an adequate strength, without burden the masonry structure with additional weight, and therefore a decreasing of the seismic vulnerability. The necessity to consider, in this ongoing research, other local mechanisms is highlighted in the unfolding of the last part of work.

• Earthquakes and Structures
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• 제10권6호
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• pp.1331-1346
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• 2016

Historical masonry structures have an important value for cultures and it is essential for every society to strengthen them and confidently transfer to the future. For this reason, determination of the seismic earthquake response, which is the most affecting factor to cause the damage at these structures, gain more importance. In this paper, the seismic earthquake behaviour of Kaya Çelebi Mosque, which is located in Turkey and the restoration process has still continued after 2011 Van earthquake, is determined. Firstly the dynamic modal analysis and subsequently the seismic spectral analysis are performed using the finite element model of the mosque constructed with restoration drawings in SAP2000 program. Maximum displacements, tensile, compressive and shear stresses are obtained and presented with contours diagrams. Turkish Earthquake Code and its general technical specifications are considered to evaluate the structural responses. After the analyses, it is seen that the displacements and compressive/shear stresses within the code limits. However, tension stresses exceeded the maximum values at some local regions. For this mosque, this is in tolerance limits considering the whole structure. But, it can be said that the tension stresses is very important for this type of the structures, especially between the stone and mortar. So, some additional strengthening solutions considering the originality of historical structures may be applicable on maximum tensile regions.