• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.352-355
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• 1998

토목섬유제품 중에서 차수재조 널리 사용되는 지오멤브레인은 1$\times$$10^{-12}$의 낮은 투수계수를 갖고 있지만 시공전후 찢어지거나 구멍이 뚫리게 되면 침출수의 유출이 발생하여 환경오염을 일으키게 된다. 이를 보완하기 위해 친수성과 팽윤성이 큰 벤토나이트 물질을 이용한 Geosynthetic Clay Liner(GCL) 복합재료가 개발되었다. GCL은 지오텍스타일이나 지오멤브레인사이에 벤토나이트를 충진시키고, 접착제 또는 니들펀칭(needle-punching)이나 스티칭(stitching)과 같은 기계적인 방법으로 결합한 복합재료이다. (중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.66-75
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• 2002

해양공학에 관련된 문제를 접근하는 방법은 이론해석, 수치해석, 수리모형실험으로 정리될 수 있다. 최근 컴퓨터의 발달로 수치실험기법이 급격한 발전을 보이고 있으나, 실해역의 복잡한 환경 특성을 모두 고려한 수치모델은 아직 개발되지 못한 상태이므로 수리모형실험은 해양환경 특성을 규명하는데 있어 여전히 중요한 기법의 하나로 남아있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.285-286
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• 2003

폴리우레탄은 복합재료의 함침 및 코팅용으로 가장 보편적으로 사용되는 수지이다. 폴리우레탄-부직포 복합소재는 폴리에스테르 또는 나일론과 같은 합성섬유로 제조된 부직포에 폴리우레탄으로 함침한 후 다시 폴리우레탄으로 코팅함으로써 소재의 단위 무게 당 폴리우레탄이 차지하는 비율이 매우 높고, 최종제품의 물성에 많은 영향을 끼치므로 이와 관련한 연구는 주로 기능성 및 내구성을 부여하는데 맞춰지고 있다[1]. (중략)

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.827-832
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• 1998

Recently, Carbon Fiber Sheets(CFS) have been used for strengthening the deteriorated RC beams and bridge decks because of its resistant capacity of corrosion and easy repairing works. In this study, the static test tare performed on RC bridge decks strengthened with CFS. Test results show that ultimate strength of specimens strengthened with CFS is increased as 15~26% comparing to the control specimen.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.585-593
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• 2010

On the basis of the strain-based shear strength model developed in the previous study, a strength model was developed to predict the direct punching shear capacity and unbalanced moment-carrying capacity of interior and exterior slab-column connections. Since the connections are severely damaged by flexural cracking, punching shear was assumed to be resisted mainly by the compression zone of the slab critical section. Considering the interaction with the compressive normal stress developed by the flexural moment, the shear strength of the compression zone was derived on the basis of the material failure criteria of concrete subjected to multiple stresses. As a result, shear capacity of the critical section was defined according to the degree of flexural damage. Since the exterior slab-column connections have unsymmertical critical sections, the unbalanced moment-carrying capacity was defined according to the direction of unbalanced moment. The proposed strength model was applied to existing test specimens. The results showed that the proposed method predicted the strengths of the test specimens better than current design methods.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.5
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• pp.605-613
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• 2007

The purpose of this study is to develop a structural analysis system of LNG pump tower structure. The system affords to build optimized finite element model and procedure of the pump tower structure. The pump tower structure is one of the most important components of LNG (liquefied natural gas) carriers. The pump tower structure is subject to sloshing load of LNG induced by ship motion depending on filling ratio. Three typer of loading components, which are thermal, inertia and self-gravity are considered in the analysis. The finite element analysis is performed with ANSYS commercial code. The failure of each members can be evaluated of API unity and punching shear in ABS rule. The GUI is newly developed using Tcl/tk script language. All these design and analysis procedures are embedded in to the analysis system successfully.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.413-420
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• 2014

The purpose of this study is to experimentally investigate the shear behavior of flat plate that reinforced by embedded GFRP(glass fiber reinforced polymer) plate with openings. Shape of the GFRP shear reinforcement is a plate with several openings to ensure perfect integration with concrete. The test was performed on 7 specimens to check shear strength of flat plate that reinforced by GFRP plate. The parameters include the spacing of the shear reinforcement and amount of the shear reinforcement. The result of test showed that when amount of shear reinforcement was increased, shear strength improved. The result of test showed that maximum shear strength was confirmed when spacing of shear reinforcement was 0.3d. The calculation of the shear strength of reinforced flat plate with GFRP plate based on the KCI was compared with the test results.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.185-188
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• 2008

Flat plate system has structural weakness such as punching shear. Punching shear resistance can be increase by using a lager column section and effective depth, higer concrete compressive strength, and more flexural reinforcement ratio. But using a shear reinforcement is most economical, enable, workable solution in flat plate. The slab with thickness smaller than 250mm can not perform effectively due to insufficient development length of shear reinforcement in the slab. In case of proposed reinforcements, since the shear reinforcements were installed between the top bar and the bottom bar, shear elements generated slip failure before they reached yield. strength. effect of anchorage strength were effective anchorage length, concrete strength, diameter of shear element and anchorage detail. considering effect of slab thickness and concrete strength, formula of K factor propose in thin flat plate slab. by considering effect of anchorage length and concrete strength, strength of shear reinforcement will be computed correctly in thin flat plate slab.

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.213-220
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• 2004

This paper deals with an enhanced structural capacity of reinforced concrete bridge deck strengthened with carbon fiber rod (CFR) which is subjected to monotonic and cyclic loads. Strengthening variables considered in this test were evenly and unevenly strengthening type. To evaluate strengthening capacity for these two strengthening types, load-carrying capacity and crack and failure pattern from the failure test were analyzed and fatigue response were examined. According to the test results, all the strengthened specimens showed punching shear failure as a result of premature failure of bonding interface between mortar and concrete. In the case of strengthening capacity, it was observed that the strengthened specimens was more effective in strength, stiffness and fatigue endurance limit than the unstrengthened specimen. In addition, the unevenly strengthening method (CR-UE) was more effective than the evenly strengthening method (CR-E).

• Advances in Computational Design
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• v.3 no.1
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• pp.49-69
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• 2018

This paper shows an optimal design for reinforced concrete rectangular combined footings based on a criterion of minimum cost. The classical design method for reinforced concrete rectangular combined footings is: First, a dimension is proposed that should comply with the allowable stresses (Minimum stress should be equal or greater than zero, and maximum stress must be equal or less than the allowable capacity withstand by the soil); subsequently, the effective depth is obtained due to the maximum moment and this effective depth is checked against the bending shear and the punching shear until, it complies with these conditions, and then the steel reinforcement is obtained, but this is not guaranteed that obtained cost is a minimum cost. A numerical experimentation shows the model capability to estimate the minimum cost design of the materials used for a rectangular combined footing that supports two columns under an axial load and moments in two directions at each column in accordance to the building code requirements for structural concrete and commentary (ACI 318S-14). Numerical experimentation is developed by modifying the values of the rectangular combined footing to from "d" (Effective depth), "b" (Short dimension), "a" (Greater dimension), "${\rho}_{P1}$" (Ratio of reinforcement steel under column 1), "${\rho}_{P2}$" (Ratio of reinforcement steel under column 2), "${\rho}_{yLB}$" (Ratio of longitudinal reinforcement steel in the bottom), "${\rho}_{yLT}$" (Ratio of longitudinal reinforcement steel at the top). Results show that the optimal design is more economical and more precise with respect to the classical design. Therefore, the optimal design presented in this paper should be used to obtain the minimum cost design for reinforced concrete rectangular combined footings.