• Architectural research
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• 제3권1호
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• pp.45-52
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• 2001

In this paper, a pressurized single vertical arch and a pressurized leaning arch composed of flexible fabric material are considered. These arches have also been considered as a possible support structure for the tent-like structures. Two different boundary conditions are considered in leaning arches with fixed bases and pinned bases. The behaviors of the leaning arches are investigated for two tilt angles as 15, 30. For each angle, two loading conditions are considered as uniformly distributed load and wind loads. The F.E.M. is used through the all analysis procedures. For the results, load-deflection relationships, buckling modes, differences between two boundary conditions and deformed configurations are discussed.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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• pp.274-279
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• 1998

The structural behaviors of a arch composed of flexible membrane are investigated. The membrane is considered as thin shell with internal pressure during FEM analysis by using ABAQUS. In the paper, a wind load and uniformly distributed vertical load are considered. As a vertical load, snow loads including applied over all and half of the structure are introduced. The ends of arch are fixed to the ground. Load-Deflections relationship, buckling mode of the structure are presented.

• Communications for Statistical Applications and Methods
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• 제22권5호
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• pp.463-473
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• 2015

We consider a nonparametric AR(1) model with nonparametric ARCH(1) errors. In order to estimate the unknown function of the ARCH part, we apply the stationary bootstrap procedure, which is characterized by geometrically distributed random length of bootstrap blocks and has the advantage of capturing the dependence structure of the original data. The proposed method is composed of four steps: the first step estimates the AR part by a typical kernel smoothing to calculate AR residuals, the second step estimates the ARCH part via the Nadaraya-Watson kernel from the AR residuals to compute ARCH residuals, the third step applies the stationary bootstrap procedure to the ARCH residuals, and the fourth step defines the stationary bootstrapped Nadaraya-Watson estimator for the ARCH function with the stationary bootstrapped residuals. We prove the asymptotic validity of the stationary bootstrap estimator for the unknown ARCH function by showing the same limiting distribution as the Nadaraya-Watson estimator in the second step.

• Steel and Composite Structures
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• 제19권2호
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• pp.405-416
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• 2015

We proposed the concept of nominal rigidity of a long-span V-shaped rigid frame composite arch bridge, analyzed the effects of structural parameters on nominal rigidity, and derived a theoretical nominal rigidity equation. In addition, we discussed the selection of the arch-to-beam rigidity ratio and its effect on the distribution of internal forces, and analyzed the influence of the ratio on the internal forces. We determined the delimitation value between rigid arch-flexible beam and flexible arch-rigid beam. We summarized the nominal rigidity and arch to beam rigidity ratios of existing bridges. The results show that (1) rigid arch-flexible beam and flexible arch-rigid beam can be defined by the arch-to-beam rigidity ratio; (2) nominal rigidities have no obvious differences among the continuous rigid frame composite arch bridge, V-shaped rigid frame bridge, and arch bridge, which shows that nominal rigidity can reflect the global stiffness of a structure.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2006년도 춘계학술발표대회 논문집
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• pp.53-54
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• 2006

Recently with increasing interest in the operation of life cycle, building remodeling business is spreading like a fashion. Keeping pace with the trend, the present project carried out the remodeling of an existing neighborhood facility into a religious facility based on the concepts of remodeling, reform and renovation. Basic requirements were overcoming spatial limitations, solving structural problems, meeting various functional needs, and securing a spatial size, and the project designed the interior of the building according to these requirements suggested by the owner. To overcome the low floor height of the existing space, the main sanctuary on the 1st floor had the ceiling in the form of a slant and installed indirect lighting into the resulting gaps, maximizing the depth and width of the space visually. The subsidiary sanctuary on the first basement was finished with red bricks, forming an arch using the bricks, to create religious atmosphere. However, considering the low floor height as in the 1st floor and the ceiling even lowered by the arch structure, the arch was formed threefold and the radius of the curvature of the arch was enlarged to secure a spacious feeling. The outer appearance was finished with granite on existing structure to save the cost of construction. In addition to the use of the finishing material, the structure of the arch and the frame of the opening part and the finishing of the walls were expressed with uneven surface in order to avoid the plainness of the appearance.

• 한국지반공학회논문집
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• 제32권10호
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• pp.31-40
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• 2016

트랩도어 하강이 일어나는 토체 내부에서 발생하는 흙 아치 구조의 변화를 관찰하기 위해서 광탄성 측정 기법을 이용하여 입상체의 다양한 거동을 관찰하였다. 광탄성 반응 재료로 코팅된 원주형 모형 입자를 적층하여 입상체를 구성하였다. 광탄성 기법을 이용하여 입상체 내부에서 발생하는 입자 간 접촉력 전달 구조의 변화를 촬영하여 관찰하였으며 이를 입상체 하부 로드셀에서 측정된 압력 변화 및 내부 활동면의 변화 양상과 비교 분석하였다. 트랩도어 하강 초기에 형성된 흙 아치 구조는 하강이 지속되면 붕괴되지만 다시 확장된 아치 구조가 새롭게 형성되었다. 트랩도어 하강 초기에 일치하였던 흙 아치 구조의 경계면과 활동면은 트랩도어 하강이 진행되면서 활동면이 포함된 영역이 접촉력을 잃은 영역 내부에 포함되었다.

• 한국공간구조학회논문집
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• 제15권3호
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• pp.43-49
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• 2015

A single-layerd steel lattice roof, which has 50m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by local snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the local snow load with geometrical imperfection decreased the level of buckling load significantly.

• Steel and Composite Structures
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• 제47권1호
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• pp.51-69
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• 2023

In tied-arch bridges, a properly designed connection between the arch and the deck may become crucial, since the forces in the structure may be significantly reduced. This implies substantial material savings and, consequently, cheaper constructions. The introduction of the Nielsen cable arrangement (composed of V-shaped inclined hangers) in the last century was a milestone because it was able to reduce deflections and bending moments both in the arch and in the deck. So far, the Nielsen cable arrangement has proven to be successful in traditional vertical arch bridges. However, despite its advantages, it has not been widely applied to spatial arch bridges. Thus, this article analyses the difference between the structural behavior of spatial arch bridges with Nielsen-type cable arrangements with respect to those with classical vertical hanger configurations. The main goal is to verify whether the known effectiveness of the Nielsen cable arrangement for classical arch bridges is still preserved when applied to spatial arch bridges. In order to achieve this objective, and as the first part of our study, a set of different all-steel bridges composed of vertical and inclined arches with straight decks have been compared for both cable arrangements. As a major conclusion, for planar vertical arch bridges, the Nielsen-type cable arrangement is always the most effective. In addition, it also seems that, for spatial arch bridges composed of a straight deck and an inclined arch, it still keeps most of its effectiveness as long as the arch is moderately inclined.

• Structural Engineering and Mechanics
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• 제39권6호
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• pp.751-765
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• 2011

The present paper deals with the identification of a concentrated damage in an elastic parabolic arch through the minimization of an objective function which measures the differences between numerical and experimental values of static displacements. The damage consists in a notch that reduces the height of the cross section at a given abscissa and therefore causes a variation in the flexural stiffness of the structure. The analytical values of static displacements due to applied loads are calculated by means of the principle of virtual work for both the undamaged and damaged arch. First, pseudo-experimental data are used to study the inverse problem and investigate whether a unique solution can occur or not. Various damage intensities are considered to assess the reliability of the identification procedure. Then, the identification procedure is applied to an experimental case, where displacements are measured on a prototype arch. The identified values of damage parameters, i.e., location and intensity, are compared to those obtained by means of a dynamic identification technique performed on the same structure.

• 한국산학기술학회논문지
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• 제19권10호
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• pp.24-30
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• 2018

지하공간의 수요가 증가되면서 지중구조물의 기능을 저하시키는 상재하중 및 토피증가에 대한 구조물의 안정성 문제를 해결하기 위해 많은 연구자들이 고압축성 물질을 이용한 하중저감방법 연구를 진행해왔다. 본 논문은 하수관거에 작용하는 하중을 EPS Geofoam을 활용하여 경감시키는 하중저감공법을 아치구조물에 적용하고 그 효과를 증가시키기 위한 최적의 Soft Zone 적용방법에 대해 기술하고 있다. 지반구조 상호작용을 고려한 ABAQUS 유한요소해석을 통해 아치구조물의 거동 특성을 파악하고 4가지 EPS Geofoam 형식을 해석적으로 분석하여 최적의 적용형상을 확인하였다. 해석 결과를 토대로 선정된 최적 단면 형상에 대해 아치구조물의 라이즈비, 지간길이 변화를 해석변수로 고려하여 발생하는 토압감소율을 비교하여 적용성을 분석하였다. 수치해석에서 선정한 최적 Soft Zone를 적용한 아치구조물에 발생하는 토압이 평균 78% 감소되는 것을 확인하였다. 본 연구 결과에서 EPS Geofoam의 토압 경량화 효과와 이에 대한 지중아치구조물의 적용성 평가는 지중구조물 설계 시 경제적이고 합리적인 방법을 제공해 줄 것이며, 향후 심층 지하공간에 대한 활용성 증가에 도움이 될 것이다.