• Composites Research
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• v.22 no.5
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• pp.24-29
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• 2009

In this paper, a post-tensioned reinforced concrete slab was analyzed by the specially orthotropic laminates theory. Both the geometrical and material property of the cross section of the slab was considered symmetrically with respect to the neutral surface so that the bending extension coupling stiffness, $B_{ij}=0$, and $D_{16}=D_{26}=0$. Reinforced concrete slab behave as specially orthotropic plates. In general, the analytical solution for such complex systems is very difficult to obtain. Thus, finite difference method was used for analysis of the problem. In this paper, the finite difference method and the beam theory were used for analysis. The result of beam analysis was modified to obtain the solution of the plate analysis.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.140-148
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• 1992

The free vibration problem of symmetrically laminated composite rectangular plates is formulated based on anisotropic thick plate theory including the effects of shear deformation and rotary inertia. Considering the difficulty of obtaining closed-form solutions, Rayleigh-Ritz analysis using polynomials having the property of Timoshenko beam functions as trial functions is adopted. The boundary conditions elastically restrained against rotation are accomodated as well as classical boundary conditions. From the results of numerical studies, the validity of the present method is verified. And it is also found that the adoption of thick plate theory for the vibration analysis of laminated composite plates is essential because of the relatively large shear deformation effect, and that the convergence of the Rayleigh quotient to the stationary value is less rapid in anisotropic composite plates than that in the orthotropic ones due to more complicated mode shapes of the former.

• Journal of Ocean Engineering and Technology
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• v.18 no.5
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• pp.36-42
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• 2004

Orthotropic laminates, such as [$0^{\circ}6$/$90^{\circ}6$]s and [$90^{\circ}6$/$0^{\circ}6$]s, were performed, using a commercial nonlinear finite element method. Interlaminar stress distributions, around the hole curve free-edge, were calculated. The delamination bearing strengths of pin joints were predicted, using the modified delamination failure criterion. These stress distributions were presented along the radial lines and around the free-edge of the hole. Further, three-dimensional non-linear contact analysis of orthotropic laminates was conducted to investigate the effect of friction. In this paper, laminates with a circular hole were taken to study interlaminar stresses the curved edge. This study may assist in the design of a thick composite laminate with mechanically pin joints.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.04a
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• pp.139.1-142
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• 1999

• The magazine of the Korean Society for Advanced Composite Structures
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• v.5 no.4
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• pp.12-15
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• 2014

• Composites Research
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• v.12 no.4
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• pp.33-41
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• 1999

In this paper, a simple but accurate method of vibration analysis of structural elements with or without attached mass/masses is presented. The method used has been developed by D.H., Kim since 1974. This method is very effective for the plates with arbitrary conditions and irregular sections. This method is applied to the special orthotropic plate with two opposite edges simply supported and the other two opposite edges free. Such plate represents the most of the simply supported bridges/decks, including concrete and girders-cross beam systems. Detailed illustration is given for beams and plates for easy understanding. Some laminate orientation for which the special orthotropic equations can be applied are identified.

• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.2
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• pp.59-65
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• 2010

The simple supported reinforced concrete slab bridges are analyzed by the specially orthotropic laminates theory. This method, however, may be too difficult for some practising engineers. In this paper, the result of analysis for such plate by means of the beam theory with unit width is reported. By using the "correction factor", the accurate solution for the plate can be obtained by the beam theory. By using the "correction factor", the accurate solution for the plate can be obtained by the beam theory. The plate aspect ratio considered is from 1 : 1 to 1 : 6. The result of this paper can be used for simply supported slab bridges analysis.

• Composites Research
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• v.23 no.1
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• pp.23-30
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• 2010

Most of the bridge systems, including the girders, cross-beams, and concrete decks behave as specially orthotropic plates. In general, the analytical solution for such complex system is very difficult to obtain. In this paper presented, a design method of slab bridge of simple supported made by composite materials. For the design of bridge made by the composite materials, cross-section was used the form-core shape because of this shape is economical and profitable, and for output of the stress value used finite difference method. In this paper, the rate of tensile strength reduction due to increased size was considered. Strength-failure analysis procedure, using the reduced tensile strength, was presented. And also numerical study was made for these cases.

• Journal of Korean Society of Steel Construction
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• v.17 no.5 s.78
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• pp.593-604
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• 2005

In this paper, the parametric study on the local displacement and the local moment due to a concentrated load is performed for stiffened plates with open ribs and the orthotropic rigidity ratio of stiffened plates is selected as the parameter. For estimating the local behavior, stiffened plates loaded on the center of plates between the ribs were considered and for the global behavior, stiffened plates loaded on the rib at the center of plates were analyzed. The Analyzed results for the local behavior of stiffened plates show that the increasing ratio of the local moment according to rib sizes is constant regardless of rib spaces and the ratio of the local displacement to the global displacement can be expressed as a function of the rib space and the rigidity ratio. The application of functions to examples shows good accuracy in comparison with the local behavior of stiffened plates loaded on the center of plates and the application to the orthotropic analysis of stiffened plates improves accuracy. Therefore, using functions proposed in this study, the local behavior can easily be estimated from the global behavior of stiffened plates with open ribs.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.04a
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• pp.200-210
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• 1997

This paper presents the result of analysis of special orthotropic plates supported by elastic foundation and simple supported edges. Convergence and accuracy of the solution are examined and it is verified that the solution obtained is sufficiently accurate. The effect of the spring constant, k, on deflection is studied.