• 물과 미래
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• 제20권4호
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• pp.249-256
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• 1987

유한수심의 해역중에 잠겨있는 고정된 2차원 구조물에 작용하는 파력을 경계요소법의 선형요소에 의해 해석하였다. 파력은 2차원 선형과 이론으로부터 해석하였으며, 입사파 방향은 무한히 긴 구조물의 직각방향으로 진행한다고 가정하였다. 본 연구에서는 바닥위에 놓여있는 반원 및 원형 단면 송유관, 수중에 잠겨있는 단면 송유관 그리고 임의 형상의 잠제에 작용하는 파력에 관해 해석하였다. 본 계산의 신뢰도를 검증하기 위하여 기존의 실험적, 이론적 결과 및 수치결과와 각각 비교하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.343-350
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• 1999

Orthotropic steel bridge decks are potentially liable to cause fatigue cracks due to weld defects, residual stresses, and in-plane or out-of-plane stresses. In particular, the cracks propagated through deckplate in longitudinal rib to deckplate joints occur at weld toe and weld root due to stress concentrations. Numerical parametric studies are performed to show the Influence of the parameters on the stress concentration at the connection between the longitudinal rib and the deckplate. The parameters include root gap, toe angle $\theta$, toe radius $\rho$, and weld penetration. This study provides a fundamental point for the improvement of fatigue resistance and the estimation of the fatigue crack propagation in wekded joint details.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.511-516
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• 2004

The objective of this study is to optimally design FRP-concrete members of a bridge structure. Using the GENESIS7.0 that is a commercial optimization program we performed an optimal design with design parameters that consist of height, width of FRP member, height of concrete. And we practiced an optimal design with the design variables, thickness of upper flange, bottom flange, and web. The results of these studies are summarized as follows : (1) Thickness of composite-concrete is proper at over loon (2) FRP member reaches the optimal section when the width of the FRP member is 20cm its height is 10cm and the height of the composite-concrete is 12cm.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.85-91
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• 2003

This paper presents a 3D nonlinear analysis with slip in steel-concrete hybrid deck. In this study, it was founded that the limit slip modulus could classify the states of steel-concrete hybrid deck into three parts as full-composite, partial-composite, and non-composite, considering the longitudinal behavior and end-slip as well as the yield load and ultimate load of it. Also, it proved that the stress of lower steel plate at the support was increased, because of frictional forces by reaction forces in the steel-concrete hybrid deck. The end-slip did not occur near the full-composite state, but it was largely increased as the slip modulus decreased. On the basis of the EC 4, the state of steel-concrete hybrid deck classified into brittle behavior and ductile one using the end-slip of it

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.119-126
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• 2003

In the conventional reinforced-concrete bridge deck, concrete and steels are likely to be deteriorated and corroded under the influence of noxious environment. To cope with these problems caused in the conventional reinforced-concrete bridge deck, pultruded composite bridge deck having light weight, high strength, corrosion resistence and durability is developed. Based on the previous study, Pultruded composite bridge deck is designed. For the DB24 truck load finite element analysis is performed to verify whether it meets both strength and serviceability design criteria. For the fabricated and assembled deck panel, structural testings are conducted. This paper present structural details and field application and testing results of composite bridge deck are presented. of composite bridge deck.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.185-192
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• 2003

This study presents the Optimum Evaluation of PS Concrete Deck and High Strength Two Plate Girder System. Recently, for the simplification of structure and the long length of bridge, a small number girder bridge which minimized a number of girder by two is much designed and constructed. For the structural analysis, a finite element formulation considering with even the matter of torsion in the three-dimensional problem is presented. And connectively, for the design of optimum section, an algorithm of optimum design is developed. The section of a small number girder bridge which constituted of two girders and PS Concrete Deck is optimized by using optimum program developed in this study. and two girders bridge refered in this study is proved a efficiency and a economy by being compared and checked to the general plate girder bridge with five girder and Reinforced Concrete Deck.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.749-756
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• 2006

Because of the orthotropic elastic properties and significant two-way bending action, orthotropic plate theory may be suitable for describing the behavior of concrete filled grid bridge decks. Current AASHTO LRFD Bridge Design Specification(2004) has live load moment equations considering flexural rigidity ratio between longitudinal and transverse direction, but the Korea highway bridge design specification(2005) doesn't. The Korea highway bridge standard specification LRFD(1996) considers an orthotropic plate model with a single load to estimate live load moments in concrete filled grid bridge decks, which may not be conservative. This paper presents live load moment equations for truck and passenger car, based on orthotropic plate theory. The equations of truck model use multiple presence factor, impact factor, design truck and design tandem of the Korea highway bridge standard specification LRFD(1996). The estimated moments are verified through finite-element analyses.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.29-34
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• 2006

In general, the vertical vibration problems for .strength of members and serviceability of building structures are not considered in structural design process, but the prediction of the vertical vibration is very important and essential to structural design process. This study aims to investigate the characteristics of vertical vibration in terms of the transfer of horizontal directions on the rahmen building structures. In order to examine the characteristics of vertical vibration, the modal test and the impact (heel-drop and hammer) excitation experiments were conducted several times on three building structures. The results from the experiments are analyzed and compared. with the results. The results of this study suggest that the characteristics of vertical vibration transfer in horizontal way are effected from the fundamental frequency of the slabs and excitation forces.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.483-484
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• 2000

Mudskipper로 알려진 망둑어과 어류인 말뚝망둑어 Periophthalmus modestus는 구나 기수역의 갯벌바닥에 서식하면서 간조시에는 물 밖으로 나와 육상의 갯벌을 뛰어다니거나 또는 추운 계절에는 갯벌에 굴을 파서 생활하는 amphibious habit를 갖고 있다. 말뚝망둑어와 비슷한 서식환경을 가지는 드렁허리 Monoterus albus와 Amphinous는 용존산소를 이용한 수중호흡 이외에 피부를 이용한 공기호흡(cutaneous respiration)을 병행하는 dual respiration system을 갖는 것으로 알려져 있으며 (Liem, 1967; Mittal and Munshi, 1971) 또한 쉽게 건조가 되는 연못, 농수로 또는 진흙바탕에 서식하는 Misgurnus fossilis(Jakuboski, 1958), M. anguillicauda (Park and Kim, 1999)에서도 피부를 이용한 공기호흡이 알려져 있다. 그러나 이러한 어류들의 피부구조는 말뚝망둑어 피부와 많은 차이점을 보여 주고 있는 본 조사는 말뚝망둑어의 피부의 특징을 조사하고 및 이들의 호흡체계에 대한 기초자료를 얻고자 한다. (중략)

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.414-421
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• 2001

Recently, the damping effect of building structures are greatly reduced because the use of non-structures members as like curtain wall are decreased and large open space are in need for the service of buildings. Assembly and office buildings with a lower natural frequency have a higher possibility of experiencing excessive vibration induced by human activities as like jumping, running and walking. These excessive vibration make the occupants uncomfortable and the serviceability deterioration. The common method of application of walking loads for the vibration analysis of structures subjected to walking loads is to inflict a series unit walking load and a periodic function at a node. But this method could not consider the moving effect of walking. In this study, natural frequency and damping ratio of plate structure are evaluated by heel drop tests. And new application of equivalent walking loads are introduced for vibration analysis of real slab system subjected to walking loads. The response obtained from the numerical analysis are compared well to the results measured by experimental tests. It is possible to efficiently analyze the vibration of floor which is subjected to walking loads by applying equivalent walking loads.