• 한국구조물진단유지관리공학회 논문집
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• 제17권5호
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• pp.13-20
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• 2013

구조물의 지진응답을 저감시키기 위하여 추가적인 감쇠기나 진동제어장치가 일반적으로 사용된다. 이때, 추가적인 감쇠장치의 제어성능은 대상구조물 특성의 변화 없이 검토된다. 본 연구에서는 구조물과 스마트 제어장치의 다목적 통합최적화를 수행하였고 스마트 최상층 면진시스템이 설치된 구조물의 구조물량 저감의 가능성을 분석하였다. 이를 위하여 20층 예제구조물이 사용되었으며 MR 감쇠기와 저감쇠 탄성베어링을 사용하여 스마트 면진시스템을 구성하였다. 중약진지역의 설계스펙트럼을 바탕으로 생성된 인공지진하중을 사용하여 구조해석을 수행하였다. 수치해석결과, 스마트 최상층 면진시스템이 중약진지역에 있는 구조물의 응답과 면진층 변위를 동시에 효과적으로 줄일 수 있는 것을 확인하였다. 본 연구에서 제안된 통합최적설계기법으로 구조물량 및 감쇠기 용량을 적절하게 줄이면서도 우수한 제어성능을 발휘하는 다양한 설계 대안을 제공할 수 있었다.

• 한국공간구조학회논문집
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• 제16권2호
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• pp.79-88
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• 2016

Modular buildings are constructed by assembling modular units which are prefabricated in a factory and delivered to the site. However, due to a problem of noise between floors, concrete slab is usually poured at the top or bottom level of a modular unit in Korea. This greatly increases the weight of buildings, but designing vertical members of modular units to resist overall gravity loads is very inefficient. In this study, considering domestic building construction practices, feasible structural systems for tall modular buildings are proposed in which separate steel frames and reinforced concrete core walls are designed to resist gravity and lateral loads. To verify performance, a three-dimensional structural analysis has been performed with two types of prototype buildings, i.e., a residential building and a hotel. From the results, wind-induced lateral displacements and seismic story drifts are examined and compared with their limit values. Between the two kinds of buildings, the efficiency of the proposed system is also evaluated through a comparison of the weight of structural components. Finally, the effect of a floor diaphragm on the overall behavior is analyzed and discussed.

• Smart Structures and Systems
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• 제6권7호
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• pp.811-833
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• 2010

Vibration control and health monitoring of building structures have been actively investigated in recent years but treated separately according to the primary objective pursued. This paper presents a general approach in the time domain for integrating vibration control and health monitoring of a building structure to accommodate various types of control devices and on-line damage detection. The concept of the time-domain approach for integrated vibration control and health monitoring is first introduced. A parameter identification scheme is then developed to identify structural stiffness parameters and update the structural analytical model. Based on the updated analytical model, vibration control of the building using semi-active friction dampers against earthquake excitation is carried out. By assuming that the building suffers certain damage after extreme event or long service and by using the previously identified original structural parameters, a damage detection scheme is finally proposed and used for damage detection. The feasibility of the proposed approach is demonstrated through detailed numerical examples and extensive parameter studies.

• Structural Monitoring and Maintenance
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• 제1권4호
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• pp.357-369
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• 2014

In the existing bridge management systems, assessment of the structural behavior is based on the results of visual inspections in which corresponding condition states are assigned to individual elements. In this process, limited attention is given to the correlation between bridge elements from structural perspective. Also, the uncertainty of parameters which affect the structural capacity is ignored. A system reliability-based assessment model is potentially an appropriate replacement for the existing procedures. The aim of this research is to evaluate the system reliability of existing conventional Steel-Reinforced bridge decks over time. The developed method utilizes the reliability theory and evaluates the structural safety for such bridges based on their failure mechanisms. System reliability analysis has been applied to simply-supported concrete bridge superstructures designed according to the Canadian Highway Bridge Design Code (CHBDC-S6) and the deterioration pattern is achieved based on the reliability estimates. Finally, the bridge condition index of an old existing bridge in Montreal has been estimated using the developed deterioration pattern. The results obtained from the developed reliability-based deterioration model and from the evaluation done by bridge engineers have been found to be in accordance.

• 한국실내디자인학회논문집
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• 제14권1호
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• pp.73-80
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• 2005

Open Housing System ideas were developed in Korea in the 1980s to satisfy the demand for variety indwelling spaces. This domestic attempt to apply open building principles was highly restricted and was applied only in support of middle-large size apartments rather than small size apartments. One of the problems was the conventional design of building structures. It was difficult to effectively satisfy the various lifestyles and transformation of dwellings because existing apartments were designed using a concrete wall structure approach, in which room sizes and arrangements were fixed by the placement of structural concrete walls. This was the result not only of structural analysis (other structural designs were possible) but also the result of the idea that the standard plan was suitable for a stable society and was easier to implement, and that change in social standards and technical upgrading was not going to happen. This study presents an apartment concept in which open building design methods were applied to satisfy the problem of various lifestyles and household sizes and preferences for small apartments. This concept also helps to create a more effective and long lasting building which decreases construction waste, saves resources and protects the environment by enabling the building to accommodate combining, increasing / decreasing, changing location or changing usage of rooms.

• 비파괴검사학회지
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• 제26권6호
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• pp.373-379
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• 2006

Vibration-based structural health monitoring is one of non-destructive evaluation (NDE) techniques for civil infrastructures. This paper presents a novel fiber optic accelerometer system to monitor civil engineering structures and a successful application of the novel sensor system for measuring ambient vibration of a real building structure. This sensor system integrates the Moire fringe phenomenon with fiber optics to achieve accurate and reliable measurements. The sensor system is immune to electromagnetic (EM) interference making it suitable for difficult applications in such environments involving strong EM fields, electrical spark-induced explosion risks, and cabling problems, prohibiting the use of conventional electromagnetic accelerometers. A prototype sensor system has been developed, together with a signal processing software. The experimental studies demonstrated the high-performance of the fiber optic sensor system. Especially, the sensor was successfully used for monitoring a real building on UCI (University of California Irvine, USA).

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.29-30
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• 2012

The precast concrete column-beam structure, Green Frame, allows the main structural members such as precast concrete column and beam to be produced on the site, resulting in a reduction of transportation cost and the margin of plant. However, existing plywood from for in-situ production of precast concrete members has problems like putting in inordinate human resource, falling-off in quality and workability. To solve those problems, form system for in-situ production of precast concrete members shall be developed. In this regard, this study aims to analyze the structural concept of from system for in-situ production. The result of this study will use for development of form system for in-situ production.

• Structural Engineering and Mechanics
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• 제49권6호
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• pp.687-703
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• 2014

This paper develops a new nonlinear model for active control of three-dimensional (3D) irregular building structures. Both geometrical and material nonlinearities with a neuro-controller training algorithm are applied to a multi-degree-of-freedom 3D system. Two dynamic assembling motions are considered simultaneously in the control model such as coupling between torsional and lateral responses of the structure and interaction between the structural system and the actuators. The proposed control system and training algorithm of the structural system are evaluated by simulating the responses of the structure under the El-Centro 1940 earthquake excitation. In the numerical example, the 3D three-story structure with linear and nonlinear stiffness is controlled by a trained neural network. The actuator dynamics, control time delay and incident angle of earthquake are also considered in the simulation. Results show that the proposed control algorithm for 3D buildings is effective in structural control.

• 국제초고층학회논문집
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• 제7권1호
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• pp.17-32
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• 2018

This paper explores the function of a structural skin with an embossed surface applicable to use for tall building structures. The major diagrid system with a secondary embossed surface structure provides an enhanced perimeter structural system by increasing tube section areas and reduces aerodynamic loads by disorienting major organized structure of winds. A parametric study used to investigate an optimized configuration of the embossed structure revealed that the embossed structure has a structural advantage in stiffening the structure, reducing lateral drift to 90% compared to a non-embossed diagrid baseline model, and results of wind load analysis using computational fluid dynamics, demonstrated the proposed embossed system can reduce. The resulting undulating embossed skin geometry presents both opportunities for incorporating versatile interior environments as well as unique challenges for daylighting and thermal control of the envelope. Solar and thermal control requires multiple daylighting solutions to address each local façade surface condition in order to reduce energy loads and meet occupant comfort standards. These findings illustrate that although more complex in geometry, architects and engineers can produce tall buildings that have less impact on our environment by utilizing structural forms that reduce structural steel needed for stiffening, thus reducing embodied $CO^2$, while positively affecting indoor quality and energy performance, all possible while creating a unique urban iconography derived from the performance of building skin.

• 한국구조물진단유지관리공학회 논문집
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• 제17권6호
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• pp.40-49
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• 2013

본 연구는 구조해석 프로그램 MIDAS-Gen을 사용하여 80층 건물의 구조분야에 대한 계획설계를 실시한 후에 캡 트러스가 설치된 초고층건물의 아웃리거 구조의 최적위치에 대하여 연구하는 것을 목적으로 하였다. 이 논문에서 구조해석의 주요한 변수는 아웃리거 위치와 주요한 구조요소 (아웃리거, 외곽기둥, 전단벽 등)의 강성이다. 캡 트러스가 설치된 초고층건물의 아웃리거 구조의 최적위치를 찾기 위하여 초고층건물의 구조설계에서 가장 중요하게 고려해야하는 요소의 하나인 최상층의 수평변위를 분석하고 고찰하였다. 본 연구의 결과, 아웃리거 위치와 아웃리거, 외곽기둥, 전단벽과 같은 주요한 구조요소의 강성은 최적의 아웃리거 위치에 영향을 주는 것으로 나타났다. 그리고 본 연구의 결과는 초고층건물의 수평변위를 최소화시키는 최적의 아웃리거 위치를 결정할 수 있는 기본적인 엔지니어링 자료를 제공하는 것으로 나타났다.