• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.153-156
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• 2008

본 연구의 목적은 와이어로프와 T형 강판으로 비부착 외부 보강된 기둥의 휨 거동을 평가하는데 있다. 이를 위해 중심축하중과 횡하중을 동시에 받는 보강된 기둥 3개와 무보강 기둥 1개가 실험되었다. 모든 기둥 시험체의 단면 크기 및 주철근과 내부 띠철근 배근 특성은 동일하게 하였다. 와이어로프의 배근 간격은 ACI 318-05 설계기준에서 제시하는 최소 띠철근 배근간격의 1.0 $^{\sim}$ 0.5배인 40 $^{\sim}$ 80mm로 조절하였다. 실험 결과 와이어로프와 T형 강판으로 비부착 보강된 철근콘크리트 기둥은 무보강 기둥과 비슷한 휨 내력을 보였지만, 연성적 거동에서는 와이어로프와 T형 강판이 피복 콘크리트를 구속하여 뛰어난 효과를 보였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.92-99
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• 2000

The nondimensional differential equations governing the buckling loads of tapered columns with both clamped ends and its boundary conditions are derived, in which the effects of shear deformations are included. These equations are solved numerically using a numerical integration technique and a bracketing method to obtain the buckling loads of columns. Four types of cross-sectional shape are considered in the numerical examples. The parametric studies of shear deformation effects on the buckling loads such as cross-sectional shape factor, shear coefficient, ratio of modulus of elasticity, slenderness ratio and section ratio are reported in tables and figures.

• 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.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.949-954
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• 2006

The purpose of this paper is to investigate the stability of tapered columns with clamped one end and carrying a tip mass of rotatory inertia with translational elastic support at the other end. The linearly tapered columns with the solid rectangular cross-section is adopted as the column taper. The differential equation governing free vibrations of such Beck columns is derived using the Bernoulli-Euler beam theory. Both the divergence and flutter critical loads are calculated from the load-frequency curves which are obtained by solving the differential equation. The critical loads are presented as functions of various non-dimensional system parameters: the taper type, the subtangential parameter, mass ratio and spring stiffness.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.689-696
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• 2006

This paper deals with the geometrical non-linear analyses of the buckled columns. Differential equations governing elasticas of the buckled columns are derived, in which both effects of taper type and shear deformation are included. Three kinds of taper types such as breadth, depth and square tapers are considered. Differential equations are solved numerically to obtain the elasticas and buckling loads of such columns. End constraint of both clamped ends and both hinged ends are considered. The effects of shear deformation on the elastica of the buckled column and buckling load of column are investigated extensively. Experimental studies are presented that complement theoretical results of non-linear responses of the elasticas.

• 소음진동
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• 제2권3호
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• pp.203-211
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• 1992

The main purpose of this paper is to present both the natural frequencies and the first critical loads of tapered columns. The ordinary differential equation governing the free vibration for tapered columns under compressive axial force is derived. Three kinds of cross sectional shape are considered in the governing equation. The Runge-Kutta method and determinant search method are used to perform the integration of the differential equation and to determine the natural frequencies, respectively. Additionally, the bisection method is used to determine the critical loads. In numerical examples, the effects of compressive axial force on the natural frequencies of tapered columns are investigated varying the end conditions. The first critical loads of tapered columns are determined on the basis of dynamic concepts. The first critical loads of tapered columns are determined on the basis of dynamic concept. The effects of cross sectional shapes are shown and some typical mode shapes are also presented.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.175-182
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• 2001

Effective length factor approach for framed column design has long played an important design-aid role. This approach, however, is effective only when the columns are in the form of prismatic or uniform cross sections. Structural engineers who have to design or analyse framed columns with variable cross sections need some means to do their job. By using the finite element method, the stability analysis of the isolated compression members with variable cross sections and that of the framed columns are performed. The parameters considered in the stability analysis are taper and sectional property parameters of the columns, the second moment of inertia ratio of beam to column, and beam span to column height ratio. On the basis of the stability analysis results, effective length factor formulas for the columns with variable sections are derived.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1996년도 봄 학술발표회 논문집
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• pp.19-26
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• 1996

The main purpose of this paper is to investigate a more accurate behavior analysis of tapered column with initial imperfection. The nonlinear differential equations governing the deflected shapes of the tapered column with initial imperfection are derived by large deflection theory and solved numerically using the Runge-Kutta method and Regula-Falsi method. Three kinds of cross-sectional shape with simply supported end constraint are considered in numerical examples. The load versus displacement curves including the left and right end rotations are presented in figures. The effect of cross-sectional shapes on deflected shape is analyzed, and the deflected shapes of column for several initial imperfections are shown in figure.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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• pp.243-250
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• 2003

A method for the determination of effective length factors of the framed columns with sinusoidally tapered sections is proposed. In the study, the stability analysis of the single story-two equal bay, frame with tapered columns is performed first by finite element method. The changes of the critical load coefficients of frames are reprersented by algebraic equations of the analysis parameters. The effective length factor formula is expressed in terms of proposed algebraic equation. The effective length factors for the prismatic columns (α=0.0) estimated by the proposed method coincide fairly well with those determined by the analytical method.

• 한국지반공학회논문집
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• 제27권2호
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• pp.91-101
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• 2011

본 연구에서는 소성힌지를 고려한 단일 현장타설말뚝의 수평거동을 분석하기 위하여 Beam-Column 해석모델을 토대로 단일 현장타설말뚝 기초의 거동특성을 파악하고, 소성힌지를 고려한 최적설계법을 제안하였다. 단일 현장타설말뚝의 소성힌지를 지상부로 유도하기 위한 최적의 기둥-말뚝의 직경비를 분석하기 위해, 변단면 단일 현장타설말뚝의 단면조건에 따른 균열 휨모멘트를 산정하고 지반조건과 수평하중에 따른 말뚝의 거동을 해석하였다. 연구 결과, 최적의 단면 조건은 기둥/말뚝 직경비($D_c/D_p$)와 정규화된 수평균열하중($F/F_{Dc}=D_p$)의 관계를 나타내는 이중직선의 변곡점 이하 부분에서 산정할 수 있었으며, 이로부터 최적의 단면 조건을 제안하였다. 또한 실제 시공사례 분석을 통해, 깊이별 휨모멘트를 바탕으로 최소철근비 적용이 가능한 구간을 분석하였으며, 그 결과 말뚝길이($L_p$)로 정규화된 최소 철근비 적용이 가능한 한계깊이($L_{As=0.4%}$)는 말뚝 직경으로 정규화된 말뚝길이($L_p/D_p$)에 따라 선형적으로 감소하였으며, $L_p/D_p=17.5$ 이후부터는 일정한 값(${\simeq}0.3$)에 수렴함을 알 수 있었다.