• Journal of Korean Society of Steel Construction
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• 제17권5호통권78호
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• pp.537-547
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• 2005

MABB(Editor's note: Please spell out "MABB" upon first mention)is a new structural type of arch that connects arch ribs and stiffened girders with two internal arches. In this study, the static and dynamic behavior of MABB were analyzed in comparison with those of conventional arches for the investigation of the structural effect of MABB on moving loads. For the purpose of surveying the effect of internal arches on the dynamic behavior of structure, natural frequency and natural vibration mode were investigated and the static and dynamic behavior were analyzed by the method of idealizing train loads as traveling loads consisting of a group of concentrated loads. From the results, the following conclusions were known. First, it is concluded that with MABB, decreasing the section of stiffened girders is possible as compared with conventional arches because the increase of stiffness by internal arches is larger than that of the mass of internal arches. Second, MABB has the advantage of assurance of stability of dynamic behavior because the dynamic behavior of MABB on moving loads is usually investigated in a more stable way than that of conventional arches.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제14권2호
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• pp.159-171
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• 2001

평면 아치 구조물에 대해 선형 탄성 변분방정식에 기반을 둔 설계민감도 해석을 위한 일반적 이론을 개발하였다. 아치 구조물내의 임의 마디에 정의된 응력범함수를 고려하였고 이에 대한 설계민감도 공식을 유도하기 위해 전미분(material derivative) 개념과 보조(adjoint) 변수 방법을 도입하였다. 얻어진 민감도 공식은 구조해석 결과를 얻고 나면 이들로부터 단순 대수연산을 통해 계산이 되므로 적용이 간편할 뿐 아니라 해의 정확도가 높은 잇점이 있다. 본 방법은 아치의 형상을 매개변수를 통해 표현하므로 얕은 아치에 국한하지 않고 어떠한 형상도 고려가 가능하며, 나아가서 아치의 형상변화를 형상에 대해 수직뿐 아니라 접선방향도 포함하여 일반적으로 고려하므로 다양한 형상설계가 가능하다. 몇 가지 예제에서 민감도 계산을 수행함으로써 본 방법의 정확도와 효율성을 입증하였으며, 두 가지의 설계최적화 문제를 대상으로 실제로 두께 및 형상최적설계를 수행하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제4권4호
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• pp.127-135
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• 1984

This paper considers the problem of optimum shaping of steel arches subjected to general loading. The weight of arches is considered as the objective function and the appropriate combinations of section forces, material volume, arc length, and closed section area of arches are considered as the stress constraints. The shape optimization problems are formulated in terms of the design variables of sectional areas of each element. First the cost sensitivity of the design is investigated. Then the investigation comprises the search for the optimum arch form as well as the optimum area distribution along the arch. Two spaces of shape optimization algorithm will be treated, the first space corresponding to the section optimization by the Modified Newton Raphson Method, and the second space to the coordinate optimization by the Powell Method. The optimization algorithm is evaluated and the optimum span-rise ratios for the given arches are evaluated.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제19권4호
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• pp.441-447
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• 2006

This paper deals with the application of the numerical differentiation in the structural analyses. Derivative values of the geometry of structure are definitely needed for analysing the structural behavior. In this study, free vibration problems of arches are chosen for verifying the numerical differential technique in the structural analyses. The curvature parameters composed with the derivatives of arch geometry obtained herein are quite agreed with those of analytical method. Also, natural frequencies with curvature parameters obtained by using the forward fifth polynomial method are quite agreed with those in the literature. The numerical differentiation technique can be practically utilized in the structural analyses.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제33권6호
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• pp.391-399
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• 2020

In this study, the behaviors of a suction cap shaped as an arch were analyzed using finite element models. The fundamental structural behaviors of both flat- and arch-type caps were compared, and the advantages of the arch-shaped cap were explained. Moreover, the effects of geometric parameters and stiffener arrangements on the stress and deformation of the arch-shaped caps were investigated by comparisons of the changes in the behaviors of the caps. Additionally, the effects of boundary condition at the edge of the cap were analyzed to study the interactions between the cap and cofferdam walls; these results were used to derive the fundamental structural design of stiffened arch caps. Unlike flat caps, the results showed that ring stiffeners could improve the structural behaviors of arch caps remarkably, while the contributions of the radial stiffeners to the structural behaviors of the caps are dependent on constraints at the edges of the caps.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 한국전산구조공학회 2010년도 정기 학술대회
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• pp.27-30
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• 2010

TMD(Tuned Mass Damper)는 대표적인 제진장치로서 주로 고층건물, 교량 및 스타디움의 객석 등의 진동제어에 이용되고 있다. 그러나 대공간구조물과 같이 면외 방향의 강성이 매우 작은 구조물에 대한 TMD 적용에 대한 연구는 거의 전무한 실정이다. 본 연구에서는 아치구조물의 진동에 대한 TMD의 제어 성능을 TMD의 설치위치 및 거동방향에 따라서 비교분석하였다. 아치구조물은 수평지진동에 대해서는 역대칭모드인 1차 모드가 지배적이며, 연직지진동에 대해서는 대칭모드인 2차 모드가 지배적인 진동응답을 보이고 있다. 따라서 아치구조물의 효율적인 진동응답제어를 위해서는 진동모드가 탁월한 위치에 TMD를 설치하는 것이 합리적이다. 그리고 수평지진동 및 수직지진동에 대하여 TMD가 수평방향으로 거동하도록 하는 것보다 연직방향으로 움직이도록 설치하는 것이 아치구조물의 진동제어에 있어서 매우 효과적인 것으로 나타났다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.619-622
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• 2011

케이블 정착구 검토를 위해서 사장교 전 체계를 모델링하는 것은 전체모델링 해석시 많은 노력과 시간이 요구되고 해석결과의 분석 또한 어려움이 많다. 따라서 문제가 예상되는 부분만을 국부 상세해석하여 구조적 거동을 정확히 파악하는 것이 필요하다. 케이블 정착부에는 여러 보강재들로 구성되어 있어 국부해석에 어려움이 있다. 따라서 실제와 가능한 한 근접하도록 모델링을 하고 전체 구조물의 거동을 국부 상세모델에 적적히 반영할 수 있도록 경계조건을 설정하는 것이다. 본 논문에서는 부산 지하철 4호선의 아치형 사장교를 국내 범용 구조해석 프로그램인 MIDAS/CIVIL을 이용하여 아치리브와 거더정착구 모델링을 실시하였다. 해석 후 해석의 타당성을 검토하고 정착부의 안전성을 확보할 수 있는지 검토 분석 하고자 한다.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제22권1호
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• pp.15-23
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• 2009

Masonry structures that are very strong in compression fail due to the instability of structural shape of geometry rather than the material stress limit. Considering such structural behavior, the use of the limit theorem that focuses on structural collapse mechanisms is more appropriate for the evaluation of the structural safety of stone voussoir arch bridges. This paper is to investigate structural performance of the stone arch bridges constructed using dry construction method in Korea based on the limit theorem and to exploit the result to develop a system for an structural safety margin. It is expected that this study will help us understand structural behavior of stone voussoir arch bridges in Korea. Also, it will provide a guideline to make engineering decision from the viewpoint of the maintenance of cultural heritages.

• Journal of Korean Association for Spatial Structures
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• 제8권5호
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• pp.9-13
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• 2008

• Journal of the Korea institute for structural maintenance and inspection
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• 제26권3호
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• pp.55-63
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• 2022

A modular underground arch structure using steel and concrete has been proposed as a structure that has a simple construction process and can effectively resist cross-sectional forces generated during construction and use. Structural behavior of modular underground arch was evaluated about span length less than 15m through 3D structural analysis and test. In general, 2D and 3D structural analysis methods may be applied for structural analysis such as underground arch and tunnels. However, if a 2D or 3D structural analysis method is applied to evaluate the structural safety of a modular underground arch structure, it is difficult to model for structural analysis and it may take an excessively long time to interpret. Therefore, it may not be reasonable as a structural analysis method for considering the structural safety and earth pressure in the design process of a modular underground arch structure. In addition, when a modular underground arch structure is configured for span lengths to which the predetermined cross-section is applicable, it may be reasonable to evaluate only the safety of the structure and cross-section according to the cross-section and load conditions. Therefore, in this study, a structural analysis model using frame elements was proposed for efficient structural safety evaluation. In addition, structural analysis results of the 2D structural analysis model and the simplified analysis model using frame elements were compared, and the structural safety of the modular underground arch structure for a span length of 20m was evaluated with a simplified analysis method.