• Wind and Structures
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• 제3권4호
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• pp.255-266
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• 2000

Wind-induced interference effects on a building are the result of one or more adjacent buildings modifying the flow of wind around it, which may result in a significant increase or decrease in wind loads on the building. Wind loading standards and codes of practice offer little guidance to the designer for assessing the effects of interference. Experimental results on interference effects indicate that code recommendations may be significantly low (unsafe) or uneconomically conservative. The paper presents results of an extensive experimental program to study the wind flow mechanisms and to quantify the extent of wind load modifications on buildings due to interference effects. These results have been simplified and presented from the point-of-view of design and codification for the case of two buildings. Based on these results, general guidelines and limiting conditions defining wind interference are formulated and discussed.

• Earthquakes and Structures
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• 제6권1호
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• pp.71-87
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• 2014

Interaction between closely-spaced buildings subject to earthquake induced strong ground motions, termed in the literature as "seismic pounding", occurs commonly during major seismic events in contemporary congested urban environments. Seismic pounding is not taken into account by current codes of practice and is rarely considered in practice at the design stage of new buildings constructed "in contact" with existing ones. Thus far, limited research work has been devoted to quantify the influence of slab-to-slab pounding on the inelastic seismic demands at critical locations of structural members in adjacent structures that are not aligned in series. In this respect, this paper considers a typical case study of a "new" reinforced concrete (R/C) EC8-compliant, torsionally sensitive, 7-story corner building constructed within a block, in bi-lateral contact with two existing R/C 5-story structures with same height floors. A non-linear local plasticity numerical model is developed and a series of non-linear time-history analyses is undertaken considering the corner building "in isolation" from the existing ones (no-pounding case), and in combination with the existing ones (pounding case). Numerical results are reported in terms of averages of ratios of peak inelastic rotation demands at all structural elements (beams, columns, shear walls) at each storey. It is shown that seismic pounding reduces on average the inelastic demands of the structural members at the lower floors of the 7-story building. However, the discrepancy in structural response of the entire block due to torsion-induced, bi-directionally seismic pounding is substantial as a result of the complex nonlinear dynamics of the coupled building block system.

• 한국지반환경공학회 논문집
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• 제15권10호
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• pp.23-28
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• 2014

최근 도심재개발사업의 증가로 기존 건물 철거 후 신축공사를 하는 사례가 증가하는 추세이다. 그러나 현재까지의 연구는 신축공사에 따른 인접굴착이 지하철 터널에 미치는 영향 검토에 국한되어 왔다. 이에 따라 기존 주차장 건물을 철거한 후 신축공사가 이루어지는 ${\bigcirc}{\bigcirc}$건물 신축사업을 연구대상으로 선정하여 상부 건물 철거 등으로 인한 하중제하 및 하중재하에 따른 지하철 터널에 미치는 영향 검토를 수행하였다. 수치해석은 기존 건물 철거를 고려한 경우와 고려하지 않은 경우에 대해 MIDAS/GTS를 사용하여 3차원 수치해석을 수행하고 터널 변위 및 부재력 결과 분석을 통해 기존 건물 철거가 지하철 터널에 미치는 영향을 검토하였다. 그 결과 기존 건물 철거를 고려하는 경우가 고려하지 않는 경우보다 지하철 터널에 미치는 영향이 더 큰 것으로 나타났다.

• 한국소음진동공학회논문집
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• 제19권12호
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• pp.1269-1280
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• 2009

This study was performed to construct sound performance DB of royal palace buildings and to examine the special quality more scientifically. Research target of royal palace were Changdeokgung and Gyeongbokgung. Sound insulation performance between the adjacent room and facade, room acoustics of Pyeonjeon and Chimjeon which is representative building in royal palace were examined through field measurement. Measured values of RT($T_{mf}$) at Pyeonjeon were 0.78 sec. and 1.03 sec. in Seonjeongjoen and Sajeongjoen, respectively. The RTs of both Pyeonjeon buildings were estimated suitable for speech and lecture considering their volume. The RT($T_{mf}$)s at Chimjeon were measured in range of 0.29~0.55 sec. This meant that the acoustic energy in rooms was decreased by sound transmission through mulberry paper(Hanji) of traditional windows and doors. As a sound insulation performance, the single-number quantities($D_{ls,2m,nT,w}$) of the building facades in Pyeonjeon and Chimjeon were measured 4~20 dB. Also the single-number quantities($D_{p,w}$) between the adjacent rooms in Chimjeon were measured 3~18 dB. Sound insulation performance of traditional building elements such as window and door depended strongly on their layers and area.

• 한국지반공학회논문집
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• 제21권10호
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• pp.99-112
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• 2005

도심지에서의 지반굴착은 배면지반의 변위와 그에 따르는 건물의 손상을 유발시킨다. 굴착에 의한 지반변위의 예측과 굴착면 주변에 위치한 건물의 손상 위험도 평가는 설계단계에서 필수적인 요소이다. 본 논문에서는 기존의 굴착에 의한 지반변위 예측기법인 Peck의 방법과 Bowles의 방법을 조합하여 지보굴착에 따르는 배면지반 변위예측방법을 제안하였다. 또한, 배면지반의 Green-field 뒤틈각과 수평변형률을 이용한 인접건물 손상위험도 평가기법을 제안하였다. 이 기법은 싱가폴에서 시공중인 대규모 지반굴착공사의 설계에 성공적으로 적용되었다.

• 한국지반공학회지:지반
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• 제14권2호
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• pp.107-126
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• 1998

터널굴착으로 발생되는 지반침하는 지상구조물의 변형을 유발할 수도 있으므로 터널굴착 전에 지상구조물의 안전성 평가가 요구된다. 이러한 변형에 대한 구조물의 안전성을 평가하기 위하여 본 연구에서는 터널현장의 지반침하를 예측하고, 이를 기반으로 지상구조물의 안정성 평가를 수행하는 전문가 시스템 NESASS(Neural Network Expert System for Adjacent Structure Safety analysis)를 개발하였다. NESASS는 인공신경망을 이용, 터널현장의 지반침하 계측자료로 작성된 데이터베이스 자료를 학습자료로 하여 학습을 수행하고, 이를 기반으로 터널현장의 지반침하 트라프를 추론한다. 또한 일반구조물의 안전성을 평가하는데 이용되고 있는 인자, 즉 각변형(angular distortion)과 처징비 (deflection ratio) 등을 이용하여 지상건물의 안전성을 평가함과 아울러 Dulacska의 균열평가 모델 을 이용하여 건물의 균열양상을 예측한다. 본 연구에서는 서울지하철 현장을 대상으로 113개 계측측선의 지반침하 계측자료를 수집 정리하고 지반침하의 주 영향인자들을 선정하여. 이들을 데이터베이스화하였다. 그리고 인공신경망 구조에 관련된 매개변수 연구를 수행하여 구축된 데이터베이스에 대한 최적 인공신경망 모델을 선정하였다. 또한 현장자료와의 비교를 통하여 NESASS의 지반침하 예측능력을 조사하고, 현장자료를 이용하여 지상구조물에 대한 안전성 평가의 신뢰성을 평가함으로써 NESASS의 실무 적용성을 확인 하였다.

• Wind and Structures
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• 제11권1호
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• pp.1-18
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• 2008

Interference effects in five square tall buildings arranged in an L- or T-shaped pattern are investigated in the wind tunnel. Mean and fluctuating shear forces, overturning moments and torsional moment are measured on each building with a force balance mounted at its base. Results are obtained at two values of clear separation between adjacent buildings, at half and a quarter building breadth. It is found that strong interference effect exists on all member buildings, resulting in significant modifications of wind loads as compared with the isolated single building case. Sheltering effect is observed on wind loads acting along the direction of an arm of the "L" or "T" on the inner buildings. However, increase in these wind loads from the isolated single building case is found on the most upwind edge building in the arm when wind blows at a slight oblique angle to the arm. The corner formed by two arms of buildings results in some wind catchment effect leading to increased wind pressure on windward building faces. Interesting interference phenomena such as negative drag force are reported. Interference effects on wind load fluctuations, load spectra and dynamic building responses are also studied and discussed.

• KIEAE Journal
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• 제15권4호
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• pp.53-60
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• 2015

Purpose: Subway in Seoul, Korea is an important urban mass transportation system as it carries more than 4 million people a day. To support this important mission, subway entrances were designed and installed to maximize accessibility to the stations. However, a uniform plan by the national government guided quantity and layout of the subway entrances. Therefore, the plan did not consider unique characteristics of each station area and reorganization of the subway entrance system is required to improve pedestrian environment. Method: This study grouped the subway entrances into specific patterns to propose reorganizing schemes. The authors conducted field surveys, examined case studies and proposed an entrance reorganizing plan for each type. Result: The study recommends subway entrances be installed inside adjacent building when large commercial or office complexes are nearby. The authors proposed installing a bridge connecting the stations and adjacent buildings for elevated entrances. This would be only possible when there are commercial or office facilities nearby with enough floor space. The study summarizes the pros and cons of each solution. To translate our proposals into realities, various incentives should be given to building or land owners. This study made suggestions as to which kinds of incentives exist and be effective in a range of situations.

• Earthquakes and Structures
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• 제1권3호
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• pp.231-252
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• 2010

Previous research on pounding between seismically isolated buildings during earthquakes has been focused on impacts at the bases of structures and the effect of simultaneous interactions at the bases and at the superstructures has not been studied in details. In this paper, the seismic responses of adjacent buildings supported on different or similar base systems considering impacts between bases and superstructures are numerically investigated. The study is carried out in three parts for the two types of adjacent buildings: (i) both structures have fixed bases; (ii) one structure has fixed base and the other is seismically isolated and (iii) both structures have base isolation systems. The results of the study indicate that the pounding-involved responses of the buildings depend mainly on the type of structural base systems and on the structural parameters of both buildings. For the base-isolated building, the variation of the peak accelerations and displacements of the storeys have been found to be relatively low. On the other hand, significant differences have been observed for the fixed base building. The results of the parametric study conducted for different values of the gap size between colliding structures show the reduction in the peak base displacements as the gap distance decreases.

• 한국전산구조공학회논문집
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• 제17권4호
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• pp.433-442
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• 2004

본 논문에서는 이웃한 빌딩의 기초가 서로 상이한 경우, 구조물과 지반의 상호작용에 대한 지진응답해석을 하였다. 세 가지 시스템에 대한 두 가지 모델에 대하여 연구하였다. 첫째 모델의 경우에는 빌딩은 프레임모델로 지반은 그리드모델로 설정하였고, 둘째 모델의 경우에는 구조물과 지반을 평면응력과 평면변형률로 모델화하였다. 또한 변형된 관성모멘트는 지반의 탄성모듈과 함께 구조물의 단면력에 영향을 미치므로 함께 고려되었다. 근사해석으로는 유한요소법과 응답스펙트럼이 적용되었으며 제시된 예를 통하여 안전성을 논증하였다.