• Magazine of the Korea Concrete Institute
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• v.28 no.1
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• pp.46-50
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• 2016

• Magazine of the Korea Concrete Institute
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• v.24 no.1
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• pp.61-64
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• 2012

• Journal of Korean Society of Steel Construction
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• v.25 no.5
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• pp.555-567
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• 2013

Slim floor system using deep decks has been developed and employed in Europe to reduce the floor height of steel structures. Although long span buildings involving the issue of reducing floor height are being increasingly built in Korea, employing deep decks in more than 7m long span structures is likely to cause problems associated with excessive deflection. This study is applied to the long-span concrete casting of the deep deck plate usability of deflection due to bending and torsional instability of open cross-section, as a way to improve the problem of cap plates are suggested, and the optimum length of reinforcement and location are derived from theoretic estimation. The cap plates are placed on the deep decks with regular intervals to overcome the instability of open sections, improve the stiffness of the sections and control the deflection at the centers. The improvement in flexural capacity associated with the location of the cap plates and the length of reinforcement are verified through analysis and test.

• Magazine of the Korea Concrete Institute
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• v.3 no.3
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• pp.141-148
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• 1991

Investigations on the behavior of steel fiber reinforced high strength concrete beams subjected to predominant shear are accomplished to determine their diagonal shear strength including ultimate shear strength. The par¬ameters varied were the fiber volume fraction(Vf) of the steel-fibers and shear span to depth ratio(a/d). The test result show that diagonal shear strength and ultimate shear strength are increased significantly due to crack arrest mechamsm. Predictive equations are suggested for evaluating the diagonal cracking strength and ultimate shear strength of the fiber reinforced high strength concrete beams.

• Journal of the Korea Concrete Institute
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• v.24 no.6
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• pp.677-684
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• 2012

In recent years, extension of life span of buildings is becoming an important issue in our society. To improve the life span of buildings, rhamen structure construction and long-spanned structures are advantageous. And in order to achieve this goal, structural elements of buildings must be light and slender. As an alternative method, general porous slabs are used frequently domestically and internationally. But the study on the porous slabs using T-deck plate and assembly of light weight precast construction is insufficient at present. In this study, flexural and fatigue tests were performed on six specimens to verify structural performance and serviceability. The main parameters of the specimens were light weight and T-deck plate construction possibility as well as slab thickness. The test results indicated that the strength of porous slabs using T-deck plate and assembly of light weight were much better than general RC slabs and porous slabs without T-deck plate. And stiffness was much better than that of other tested slabs.

• Journal of Institute of Convergence Technology
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• v.11 no.1
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• pp.29-32
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• 2021

편대비행 항공기들은 선행항공기에서 발생시킨 후류의 영향으로 후행항공기의 공력효율이 증가하는 것으로 잘 알려져 있다. 비점성 비회전 유동장에 관한 연속방정식을 지배방정식으로 사용하는 패널법은 비교적 빠른 시간 이내에 항공기의 공력특성 변화를 계산할 수 있는 장점이 있다. 본 연구에서는 편대비행 항공기들 사이의 항공기들 사이의 흐름방향 거리는 스팬길이의 2.5배로 위치시키고, 수평상대거리는 스팬길이의 -0.4~0.3배로, 수직상대거리는 스팬길이의 -0.25, -0.15.0.15.0.25배로 변화시키며 계산을 수행했다. 연구결과 선행항공기와 후행항공기의 수평상대거리 변화의 경우 주날개들이 안쪽으로 겹침이 발생하고, 수직 상대거리가 가까울수록 더 큰 공력성능 향상을 얻을 수 있었다. 편대비행 하는 후행항공기의 공력성능 향상은 선행 항공기로부터 발생한 익단 와류의 올려흐름 영향에 기인한 것이다. 선행항공기로부터 발생한 익단와류는 후행항공기의 모멘트 특성을 변화시켜 비행안정성에 영향을 미치게 된다. 향후 연구에서는 선행항공기로부터 발생한 와의 영향이 후행항공기의 모멘트 특성에 미치는 영향을 연구 할 것이다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.149-150
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• 2015

Structural beam plays a key role to carry the applied load on the floors. And then the beam have to sustain the applied load and its load-bearing capacity in fire situation. In this study to know the fire resistance performance of long span beam made of a submarine structural steels, an engineering method is used using mechanical and thermal properties of structural steel at high temperature.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.44-51
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• 2017

Recently, the parking in downtown area has caused severe problem due to the dramatic increase of possessing automobile in the country. A parking structure has been on the spotlight to solve the parking problem in downtown area. However, the overall height of parking structure is stipulated less than 8 m. Therefore, in this research, 'wide composite beam', which is possible for reducing story height and having long span, is developed and the flexural capacity of the wide composite beam is evaluated. Based on the result of the flexural test, the flexural strength of wide composite beam increased by 20% as the thickness of steel beam increased by 3 mm ($6mm{\rightarrow}9mm$) The shapes of rebar (whether it is triangle or rectangular shape) in the wide composite beam did not affect its flexural strength. The flexural strength of wide composite beam without rebar decreased by 10% compared to that of wide composite beam with rebar. In addition, the neutral axis moved upward as a load increased, but the neutral axis moved downward, when the load exceeded a certain level of load.

• Journal of Korean Society of Steel Construction
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• v.20 no.5
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• pp.601-608
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• 2008

Joints of single-layer latticed domes show various flexural behaviors according to their shapes and connecting methods. Ball joints are relatively easy to apply and build while their rigidities are relatively small and have disadvantage in long span. Welded joints have many advantages in rigidity, internal force and long span. However few experimental studies have been performed. In this paper, improved welded joint for the single layer latticed domes was proposed through both analytical and experimental analyses. Length of inserted plates, thickness of inserted plates and hole of sub steel pipes were selected as parameters for experimental comparisons and defining the effects of the selected variables.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.109-118
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• 1998

전단거동에 의해 지배되는 고강도 철근콘크리트 춤이 큰 보의 전단역학적 거동 및 전단강도특성을 고려한 이론식을 제시하고자 소성이론에 근거한 극한해석에서 상계치정리를 이용하여 이론적 전개를 하였으며, 고강도 R/C춤이 큰 보의 전단응력에 영향을 미치는 콘크리트 압축강도, 수직전단보강근 및 수평잔단보강근의 보강효과를 고려한 이론식을 제시하였으며, 수평철근 즉 주인장철근 및 수평전단보강근의 장부작용을 고려하였다. 실험결과와 비교할 때 제안식은 수직잔단보강근의 전단보강효과를 과대평가하고있으며, 수평전단보강근의 효과를 적절하게 평가하고 있음을 나타내었다. 또 전단스팬비가 0.5, 0.85인 경우에는 제안식에 의한 값이 다소 낮게 나타내, 전단스팬비가 낮은 경우는 다소 과소평가하는 것으로 나타났다.