• Journal of Korean Association for Spatial Structures
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• v.7 no.3 s.25
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• pp.79-86
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• 2007

Recently, as steel structures become higher and more long-spanned, construction of high-strength steels is increasing gradually. Application of high-strength steel can be possible to make a more light and economic steel structures by reducing thickness and space. To apply a high-strength steel to structure, criteria of high-strength steel for buckling is required. However, current specification is not sufficient for criteria of high-strength steels. In this paper, buckling behavior of high-strength steel truss columns with box sections is investigated by using three-dimensional elastic-plastic finite deformation analysis program. The criteria equation for allowable compressive stress of high-strength steel truss columns with box sections is proposed and confirmed the applicability. It is reasonable form analytical results that formulated equations after finding the upper limit of allowable axial direction compression stresses of high-strength steel truss columns. And new equation is suitable to buckling design of high-strength steel truss columns.

• Journal of the KSME
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• v.17 no.1
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• pp.40-44
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• 1977

먼저번에는(대한기계학회지 제16권 제4호 1976) 유한요소법의 중심부를 통하는 기본로선을 따라 가면서 기초 개념을 해설하였다. 이 해설에서 앞으로 취급될 사항은 다음과 같다. 1. 트러스 구조물의 정역학적 문제를 예제로 다루며 방향변환에 따르는 "변환매트릭스"해설 2. 기둥의 탄성 안정 문제를 예제로 다루며 비 선형 문제에서 등장하는 "추가 강성매트 릭스 (Incremental Stiffness Matrix)[N]의 해설 3. 1차원 문제에 있어서의 여러 가지 유한요소 해설 4. 2차원 문제에 있어서 평면형을 갖는 여러 가지 유한요소 해설 5. 2차원 문제에 있어서 곡면형을 갖는 여러 가지 유한요소 해설 6. 유한요소법의 발전 전망 7. 전자계산기 프로그래밍에 있어서의 여러문제 해설의 대상자는 공과대학 기계계열의 상급학년 학생 또는 고체역학 부문에 경력을 갖는 기술자 들로서 이 부문의 기본지식을 갖고 있는 자로 한다. 이번회에는 유한요소의 자유도 즉 미지상 수로 다루어지는 자변수의 좌표축이 바뀔 때 부수적으로 등장하는 변환 매트릭스에 대하여 해 설한다.트릭스에 대하여 해 설한다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.23-34
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• 2015

Recently a new damper system with Kogome truss structure was developed and its mechanical properties were verified based on the laboratory test. This paper presents a Kagome truss damper external connection method for seismic strengthening of RC frame structural system. The Kagome external connection method, proposed in this study, consisted of building structure, Kagome damper and support system. The method is capable of reducing earthquake energy on the basis of the dynamic interaction between external support and building structures using Kagome damper. The pseudo-dynamic test, designed using a existing RC frame apartment for pilot application of LH corporation, was carried out in order to verify the seismic strengthening effects of the proposed method in terms of the maximum load carrying capacity and response ductility. Test results revealed that the proposed Kagome damper method installed in RC frame enhanced conspicuously the strength and displacement capacities, and the method can resist markedly under the large scaled earthquake intensity level.

• Journal of Korean Society of Steel Construction
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• v.20 no.2
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• pp.303-312
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• 2008

In this paper, the seismic behavior of shear wal-frame systems is analyzed. The governing equations of the wall-frame systems with outrigger truss are formulated through the continuum approach and the whole structure is idealized as a shear-flexural cantileverwith rotational spring. The effect of shear deformation and flexural deformation of the wall-frame and outrigger trusses are considered and incorporated in the formulation of the wall-frame structures with and without outriggers are compared by using finite element analysis incorporated with the Newmark-${\beta}$ method. Numerical results are obtained and compared with the finite element package MIDAS. The proposed method is found to be simple and efficient, and provides reason ably accurate results in the early design stage of tall building structures.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.2
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• pp.137-146
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• 2005

This study presents the shape iteration method and the updated Lagrangian methods to calculate the initial tension and the reference length of cables of cable-stayed bridges. The girders and towers of cable-stayed bridge are modelled as 3-dimensional frame elements and the cable as nonlinear truss element or Ernst's cable element. Compared with the initial tensions of cables by finite element method in this study and by trial-and error method in practices, the tensions by the former are shown to be a little less than the those by the latter. The reference lengths of cables by Ernst's cable elements are almost consistent with those of cables by nonlinear truss elements. And the reference length of cables in this study are almost consistent with the arc length of beam with the same initial tension. Therefore the reference lengths of cables in cable-stayed bridges are shown to be obtained simply by the theory of beam with the initial tension calculated in this study.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.64-64
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• 2004

최근 복합재료, 신소재 등 다양한 방법을 통해 빔(beam), 바(bar), 패널(panel) 등 초경량 구조재료가 개발되고 있다. 이중 금속 내부구조재를 가진 접합판재(Inner Structured and Bonded panel, ISB panel)은 3차원 형상의 내부구조재가 강성 및 강도를 증가시키는 반면, 부피의 대부분이 비어있어 비강도 및 비강성을 크게 개선시킨다 일반적으로 다양한 트러스 형태의 금속 내부구조물은 허니컴 형상의 내부구조와 유사한 정도로 기계적 특성이 우수하다.(중략)

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.207-214
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• 2000

In this paper, a study of the effenctiveness and convergency of five damage measures for structural damage detection of 2-dimensional truss structure using the extended Kalman filtering algorithm is presented. These damage measures are associated with the change in mode shape and displacement due to structural damage. Damage measures contain the change in natural frequency, mode shape, curvature of mode shape, displacement of static force and curvature of displacement of static force. The effectiveness and convergency of these damage measures by using extended Kalman filtering algorithm are demonstrated with the numerical examples.

• Journal of Korean Association for Spatial Structures
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• v.2 no.1 s.3
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• pp.41-49
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• 2002

In this paper, a study of 2-step damage detection for space truss structures using the extended Kalman filter theory is presented. Space truss structures are composed of many members, so it is difficult to find damaged member from the whole system. Therefore, 2-step damage identification method is applied to detect the damaged members. First, kinetic energy change ratio is used to find damage region including damaged member and then detect damaged member using extended Kalman filtering algorithm in damage region. The effectiveness of proposed method is verified through the numerical examples.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1993.10a
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• pp.81-90
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• 1993

The optimum design of a structure requires the determination of the economical member size and shape of the structure which satisfies the design condition and function. In this study, the process of design automatization of three-dimensional truss structure introduces the optimization technique tests its application in the design automatization, proposes its application method and applies the example structure of the parabolic antenna truss. Using the Formex Algebra of configuration function, the structure's mesh-generation is automatized. By using the program developed in this study, the input member array, member size and load condition designer can generate the input data file for the structure analysis and optimum design. This study is aimed at the development of a design automatization system that search for tile optimum value of a structure design by observing the structure's sensitivity from the modification of member array and member property.

• Journal of Power System Engineering
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• v.8 no.1
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• pp.69-74
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• 2004

A structure-control combined optimal design problem is discussed taking a 3-D truss structure as a design object. We use descriptor forms for a controlled object and a generalized plant because the structural parameters appear naturally in these forms. We consider not only minimum weight design problem for structure system, but also suppression problem of the effect of disturbances for control system as the purpose of the design. A numerical example shows the validity of combined optimal design of structure and control systems. We also consider the validity of sensor-actuator collocation for control system design in this paper.