• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.579-584
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• 1999

In evaluating the ultimate strength of a section for a concrete flexural member, the effect of member length is not usually considered, even though the strength tends to decrease with increase of member length. In this paper the influence of specimen length on flexural compressive strength of concrete was evaluated. For this purpose, a series of C-shaped specimens subjected to axial compression and bending moment were tested using four different length-to-depth ratios(from 1, 2, 3 and 4) of specimens with compressive strength of 58 MPa. Results indicate that the reduction in flexural compressive strength with increase of length-to-width ratios was apparent. A model equation was derived using regression analyses on the experimental data. It was also founded that the effect of specimen length on ultimate strain was negligible, but its effect of the ultimate load and the displacement at center of specimen was distinct. Finally more general model equation is also suggested.

• Journal of Welding and Joining
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• 제21권6호
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• pp.40-45
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• 2003

Steel members have advantages of resisting torsion and axial compression. In design, residual stresses at the welded joint of T-shape steel pipes are one of the most important points to be considered. In this paper, characteristics of residual stresses of welded joints are clarified by carrying out 3D non-steady heat conduction analysis and 3D thermal elastic-plastic FE-analysis. According to the results, the production mechanism of residual stresses at the welded joint of T-shape steel pipe is clarified. In this paper, circumferential stresses depended on thermal histories but axial and radial stresses were more dependent on geometrical shape than thermal histories. Residual stresses in the axial direction on the lower part of pipe member were tensile, controlled by geometrical shape. However, in case of middle part, residual stresses in all the directions were controlled by thermal histories.

• 콘크리트학회논문집
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• 제11권4호
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• pp.63-71
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• 1999

In evaluating the ultimate strength of a section for a reinforced concrete flexural member, the effect of member length is not usually considered, even though the strength tends to decrease with increase of member length. In this paper the influence of specimen length on flexural compressive strength of concrete was evaluated. For this purpose, a series of C-shaped specimens subjected to axial compression and bending moment were tested using four different length-to-depth ratios (from 1,2,3 and 4) of specimens with compressive strength of 590 kgf/$\textrm{cm}^2$. Results indicate that for the region of h/c <3.0 the reduction in flexural compressive strength with increase of length-to-depth ratios was apparent. A model equation was depth of an equivalent rectangular stress block was larger than that by ACI. It was also founded that the effect of specimen length on ultimate strain was negligible. Finally more general model equation is also suggested.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.11-18
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• 1999

For the proper design of a slender compression member, the exact determination of the elastic critical load is crucial, In the cases of non-prismatic compression members, the determinations of the elastic critical load cannot be usually expressed in closed forms. h this paper, the non-symmetrically tapered compression members with arbitrary boundary conditions me analysed by using the finite element method to determine the elastic critical load. The main parameters considered in the numerical analysis are the In Parameter, $\alpha$ and the sectional property parameter, m. To generaliza the unmerical analysis, of the computed results for each sectional parameter, m are presented in algebraic equations, which agrees fairy well with those by F.E.M in most cases.

• 한국자동차공학회논문집
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• 제5권3호
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• pp.1-14
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• 1997

In this paper, collapse test of thin-walled structural member widely used for automobiles is carried out under static compression load to observe the effects of cross- sectional shape and material on the energy absorbing capacity in the viewpoint of cras- hworthiness. Specimens tested consist of two sorts(Aluminium, CFRP) and configur- ations(Circular, Square) with variation in thickness. Also, comparisons of Al circular and square specimens are made to find the influence of difference in shape on the energy absorbing capability according as the thickness of specimen varies.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.1-4
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• 2000

This paper presents the analytical results of local - global interaction buckling of orthotropic I-shape compression members. Employing the equilibrium approach, the characteristic equation for local and global interaction buckling of I-shape compression member is derived. Using the derived equation, the buckling coefficients with respect to the ratio of length to width for the I-shape column are suggested as a graphical form. In addition, graphical forms of local, global and FEM results are presents, and they are compared with those in published document.

• Steel and Composite Structures
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• 제5권5호
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• pp.345-358
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• 2005

The response of single story buildings and other case studies are investigated to observe trends in response and to develop a better understanding of the impact of some design parameters on the seismic response of CBF. While it is recognized that many parameters have an influence on the behavior of braced frames, the focus of this study is mostly on quantifying energy dissipation in compression and its effectiveness on seismic performance. Based on dynamic analyses of single story braced frame and case studies, it is found that a bracing member designed with bigger R and larger KL/r results in lower normalized cumulative energy, i.e., cumulative compressive energy normalized by the corresponding tensile energy (${\sum}E_C/E_T$), in both cases.

• 복합신소재구조학회 논문집
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• 제1권1호
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• pp.16-26
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• 2010

In this paper, we present the result of investigations pertaining to the development of the floating type photovoltaic energy generation system. Pultruded FRP has superior mechanical and physical properties compared with those of conventional structural materials. Since the FRP has an excellent corrosion-resistance and high specific strength and stiffness, the FRP material may be highly appreciated for the development of the floating type photovoltaic energy generation system. In the paper, we discussed the development concepts of the floating type photovoltaic energy generation system, briefly. The mechanical properties of the FRP structural member used in the development are investigated through the tensile and compression tests. Test results are used in the finite element analysis and the design of the system. In addition, bolted connections of the members are briefly discussed and the strengths of FRP bolted connections are estimated based on the results of experiments. The experimental results are compared with the finite element analysis results and discussed briefly. The floating type photovoltaic energy generation system is designed, fabricated, and installed successfully in site.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.161-162
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• 2010

본 연구에서는 콘크리트 구조물인 교량의 교각과 같은 압축부재의 충격하중을 정량적인 손상지수로 평가하기 위해서 동적유한요소해석 프로그램인 LS-DYNA를 이용하여 차량의 충격각도에 따른 충격도, 세장비 등을 변화시켜 case별 해석을 수행하였다. 본 연구결과를 통해 콘크리트 구조물의 거동해석 및 설계기법을 Bayesian 통계방법을 이용하여 충격하중을 받을 시의 성능기반형 설계기법을 산정하였으며, 이는 실제 충격하중에 의한 구조물의 방호성능 및 설계 시에 적절하게 적용할 수 있을 것으로 판단된다.

• 한국강구조학회 논문집
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• 제18권6호
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• pp.697-706
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• 2006

타워크레인의 횡방향 지지와 마스트의 횡강성 및 강도를 확보하기 위하여 횡하중 저항요소로서 사용되는 것이 월타이(wall tie)이다. 본 연구에서는 국내에서 가장 많이 사용되고 있는 독일 립헬사의 T형 타워크레인(기종 290HC, 작업반경: 70m, 인양하중: 12tf)을 대상으로 하고 마스트 및 월타이의 사용부재는 H형강보 구조의 구조물을 모델로 선정하여 월타이의 부재력, 월타이의 각도변화 및 각도범위에 따른 부재력의 변화를 분석하여, 실용적이고 안전한 월타이의 각도범위를 제안하여 현장기술자가 최적의 월타이를 배치할 수 있도록 하였다. 본 연구를 통하여 건축용 타워크레인의 훅크양정을 증대시키기 위하여 설치되는 횡방향지지요소인 월타이의 부재력 계산식을 구하고, 이를 프로그래밍하여 마스트 중심과 월타이 브라켓 간 거리를 변화시키면서, 월타이 각도별 월타이 부재력을 반복계산하여 월타이 부재력 특성곡선을 그리고 이를 분석하였다.