• Interaction and multiscale mechanics
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• 제1권3호
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• pp.339-355
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• 2008

A Galerkin meshfree method is presented for analyzing shear deformable cylindrical panels. Based upon the analogy between the cylindrical panel and the curved beam a pure bending mode for cylindrical panel is rationally constructed. The meshfree approximation employed herein is characterized by an enhanced moving least square or reproducing kernel basis function that can exactly represent the pure bending mode and thus meets the requirement of Kirchhoff mode reproducing condition. The variational form is discretized using the efficient stabilized conforming nodal integration with a smoothed nodal gradient based curvature. The resulting meshfree formulation satisfies the integration constraint for bending exactness. Moreover, it is shown here that the smoothed gradient preserves several desired properties which are valid for the standard gradient obtained by direct differentiation, such as partition of nullity and reproduction of a constant strain field. The efficacy of the proposed approach is demonstrated by two benchmark cylindrical panel examples.

• International Journal of Railway
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• 제8권2호
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• pp.46-49
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• 2015

In this paper, improved out-of-plane design of parabolic arches was proposed based on the current design code. The arches resist general loading by a combination of axial compression and bending actions, and the interaction formula between two extreme cases of axial and bending actions is generally used for the design. Firstly, the out-of-plane buckling strength of arches in a pure axial compression and a pure bending were studied. Then, out-of-plane design of parabolic aches under general transverse loading was investigated. From the results, it can be found that the proposed design equations provided good prediction of out-of-plane strength for parabolic arches which satisfy the thresholds for deep arches, while proposed design equations overestimated the buckling load of shallow arches.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.130-133
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• 2005

Efficient finite element method has been introduced for metallic sandwich plates subject to 3-point bending. A full model 3-point bending FE-analysis shows that plastic behavior of inner structures appears only at the load point. So, Unit structures of sandwich plates are defined to numerically calculate the bending stiffness with recurrent boundary condition of pure bending. And then equivalent models with same bending stiffness and strength of full models are designed analytically. It is demonstrated that results of both models are almost same and FE analysis method with equivalent models can reduce analysis time effectively.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.139-144
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• 2003

To apply CFT members into the bridge girders, bending behavior of CFT is to be investigated. However, pure bending tests of CFT have been rarely performed, while much of the experimental study of CFT focuses on the axial loading. In this study, ultimate bending strength of CFTs with various different thicknesses and diameters was measured and compared with behaviors of bare tubes. It shows the beneficial effect of concrete for CFT in flexure to increase strength and ductility.

• 한국정밀공학회지
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• 제21권4호
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• pp.132-139
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• 2004

The open section members have been used as the members of vehicle such as automotives, airplanes and trains. When vehicles are crashed, these members have absorption of the energy and it is necessary for retainment of the survival space, and as the result, the prediction for the displacement of members in this case of the crash of vehicles is very important. The displacements of members in this case of the crash of automotives show combined aspect of both axial collapse and bending collapse. In the rollover accident when bending collapse happen, the collapse of each members is progressed by the plastic hinge which made from bending moment, and therefore the research for the behavior of members under bending moment after collapse is necessary to determine the internal energy which the members can absorb and the deformed shapes of the members on the step of design. In this paper, the characteristics of bending collapse at the members of the open cross-section were studied with experiment and numerical analysis. We made a comparative studied of the result of the experiment, and changed the axis according to the parallel-axis theorem.

• 산업기술연구
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• 제20권B호
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• pp.131-138
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• 2000

In this paper, we would like to develop the bending collapse specific equation of aluminum members which are usually used in light-weight vehicle or electromobiles. The result of the developed equation are compared with that of test and finite element methods as the moment-rotational angle curves. Three types of aluminum members are tested with the pure bending collapse test rig. PAM-CRASH and ABAQUS program are used for finite element analysis. As the result the developed bending collapse governing equation is accurate in estimating the yield moment and the maximum moment. Especially, in the case of the local buckling and the delayed buckling, the developed equation is better effective than F.E.M.

• 대한기계학회논문집
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• 제9권1호
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• pp.18-23
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• 1985

본 논문에서는 편심 경사진 균열을 가진 판이 순수굽힘을 받는 경우에 등각사 상함수를 발견하고 등각사상법에 의한 복소응력함수를 사용하여 응력확대계수의 근사 이론식을 구하고 광탄성 실험을 통하여 비교 고찰하였다.

• Steel and Composite Structures
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• 제24권5호
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• pp.523-536
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• 2017

A layerwise (LW) formulation based on the Galerkin method is presented to investigate the three-dimensional stress state in long sandwich plate which is subjected to tension force and pure bending moment. Based on the Galerkin method and the LW discretization approach, the equilibrium equations of elasticity for the long plate are written in the weak form and discretized through the thickness of the plate. The discretized equations are written in terms of displacement components of the numerical layers. The governing equations of the plate are solved analytically for the free edge boundary conditions. The distribution of stress state especially the 3D stress state in the vicinity of the edges of the sandwich plate which is subjected to tension and pure bending is studied. In order to increase the accuracy, the out of plane stresses are obtained by integrating the equilibrium equations of elasticity. The convergence and accuracy of the predictions are studied and various numerical results are presented for distribution of the in-plane and out of plane stresses in symmetric and un-symmetric sandwich plates.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.344-351
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• 2000

In the design of plate girder web panels, it is required to evaluate accurately the elastic buckling strength under pure shear, pure bending and combined bending and shear. Currently, elastic buckling coefficients of web panels stiffened by transverse intermediate stiffeners are determined by assuming conservatively that web panels are simply supported at the juncture between the flange and web. However, depending upon the geometry and the properties of the plate girder bridge, upper juncture between the flange and web can be assumed as fixed because concrete deck prevents the rotational displacement of upper flange. In the present study, a series of numerical analyses based on finite element modeling is carried out to investigate the effects of the concrete deck, and the resulting data are quantified in simple equations.

• Journal of the Korean Wood Science and Technology
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• 제37권2호
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• pp.128-136
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• 2009

Curved glued laminated timber (glulam) is rapidly coming into the domestic modern timber frame buildings and predominant in building construction. The radial stress is frequently occurred in curved beams and is a critical design parameter in curved glulam. Three models, Wilson equation, Exact solution and Approximation equation were introduced to determine the radial stress of curved glulam under pure bending condition. It is obvious that radial stress distribution between small radius and large radius was different due to slight change of neutral plane location to center line. If the beam design with extremely small radius, it should be considered to determine the exact location of maximum radial stress. The current standard KSF 3021 was reviewed and would be considered some adjustment determining the optimum radius in curved glulam. Current design principle is that the stress factor is given by the curvature term only in constant depth of the beam, but like tapered or small radius of beams, the stress factor by Wilson equation was underestimated. So current design formula should be considered to improvement for characterizing the radial stress factor under pure bending condition.