• Structural Engineering and Mechanics
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• v.27 no.2
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• pp.149-172
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• 2007

An experimental study of five full-scale coupling beam specimens has been conducted to investigate the seismic behavior of strengthened RC coupling beams by bolted side steel plates using a reversed cyclic loading procedure. The strengthened coupling beams are fabricated with different plate thicknesses and shear connector arrangements to study their respective effects on load-carrying capacity, strength retention, stiffness degradation, deformation capacity, and energy dissipation ability. The study revealed that putting shear connectors along the span of coupling beams produces no significant improvement to the structural performance of the strengthened beams. Translational and rotational partial interactions of the shear connectors that would weaken the load-carrying capacity of the steel plates were observed and measured. The hierarchy of failure of concrete, steel plates, and shear connectors was identified. Furthermore, detailed effects of plate buckling and various arrangements of shear connectors on the post-peak behavior of the strengthened beams are discussed.

• Coupled systems mechanics
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• v.13 no.2
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• pp.133-151
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• 2024

In this paper, an improved theoretical interfacial stress analysis is presented for simply supported composite aluminum- sandwich honeycomb beam strengthened by imperfect FGM plateusing linear elastic theory. The adherend shear deformations have been included in the present theoretical analyses by assuming a linear shear stress through the thickness of the adherends, while all existing solutions neglect this effect. Remarkable effect of shear deformations of adherends has been noted in the results.It is shown that both the sliding and the shear stress at the interface are influenced by the material and geometry parameters of the composite beam. This new solution is intended for applicationto composite beams made of all kinds of materials bonded with a thin plate. Finally, numerical comparisons between the existing solutions and the present new solution enable a clear appreciation of the effects of various parameters.

• Structural Engineering and Mechanics
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• v.22 no.3
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• pp.331-349
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• 2006

The stresses and deflections in a laminated rectangular plate under thermal vibration are determined by using the moving least squares differential quadrature (MLSDQ) method based on the first order shear deformation theory. The weighting coefficients used in MLSDQ approximation are obtained through a fast computation of the MLS shape functions and their partial derivatives. By using this method, the governing differential equations are transformed into sets of linear homogeneous algebraic equations in terms of the displacement components at each discrete point. Boundary conditions are implemented through discrete grid points by constraining displacements, bending moments and rotations of the plate. Solving this set of algebraic equations yields the displacement components. Then substituting these displacements into the constitutive equation, we obtain the stresses. The approximate solutions for stress and deflection of laminated plate with cross layer under thermal load are obtained. Numerical results show that the MLSDQ method provides rapidly convergent and accurate solutions for calculating the stresses and deflections in a multi-layered plate of cross ply laminate subjected to thermal vibration of sinusoidal temperature including shear deformation with a few grid points.

• Journal of the Korea Institute of Military Science and Technology
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• v.3 no.1
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• pp.146-154
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• 2000

Buckling behavior was studied for the square plate with bead and hole under shear load. Plates were made to examine the effect of bead and hole to the material, aluminum and composite, the effect of flange angle, bead height and bead radius of curvature. There was little difference between buckling loads obtained by the experiment and Rayleigh-Ritz method to the plate. Buckling load could be increased highly when stress concentration to the hole was dispersed effectively using flange. A well-designed plate using bead and flange showed 3 times as much as stiffness to the plate without bead and flange.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.548-549
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• 2014

Omni-directional shear-horizontal magnetostrictive patch transducers have a disadvantage that magnetic flux leakage into the plate when it is installed on a ferromagnetic plate. The leakage produces poor transduction efficiency and unwanted wave mode excitation which should be avoided in guided wave inspections of large plate-like structures. In order to resolve these problems, we newly developed a method to reduce the leakage into the plate. In the method, the patch and the magnet are vertically lifted off and their optimal positions are determined by numerical simulations. Also, the verification of the developed method is successfully verified by experiments.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.2
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• pp.324-345
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• 2015

A new procedure for determining properties of thick plate finite elements, based on the modified Mindlin theory for moderately thick plate, is presented. Bending deflection is used as a potential function for the definition of total (bending and shear) deflection and angles of cross-section rotations. As a result of the introduced interdependence among displacements, the shear locking problem, present and solved in known finite element formulations, is avoided. Natural vibration analysis of rectangular plate, utilizing the proposed four-node quadrilateral finite element, shows higher accuracy than the sophisticated finite elements incorporated in some commercial software. In addition, the relation between thick and thin finite element properties is established, and compared with those in relevant literature.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.53-56
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• 2004

Recently, post tension flat plate slab system is widely used for a new slab structural system. Slab-column connections may fail in brittle manner by punching shear. Flat plate slabs have been widely used for gravity load resisting system in buildings. Lateral resistance usually provided by shear walls or moment resisting frames. Since plat plates move together with lateral loading system during earthquake or wind, it is important to evaluate the gravity resistance under a drift experienced by lateral force resisting system during either design earthquake or wind. Thus, this study investigated post tension flat plate slab systems whether they have sufficient strength and deformability to resist gravity loads during specified drift levels. Experimental research was carried out.

• Journal of Ocean Engineering and Technology
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• v.15 no.1
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• pp.85-91
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• 2001

A study for the structural strength analysis on the doubler plate subjected biaxial in-plane compression and shear load has been performed through the systematic evaluation process. In order to estimate the proper static strength of the doubler plate, non-linear elasto-plastic analysis is introduced. Gap element modeling for contact effect between the main plate and the doubler is prepared and nonlinear analysis procedures are illustrated based on MSC/N4W. In addition, some design guides are suggested through the consideration of several important effects such as corrosion of main plate, doubler width, doubler length and doubler thickness. Finally, theses result are compared with a developed design formula based on the buckling strength and general trends. The design guides, according to the variation of design parameters are discussed.

• Structural Engineering and Mechanics
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• v.15 no.2
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• pp.249-267
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• 2003

In this study, circular plates subjected to general type of loads and supported on a two-parameter elastic foundation are analysed. The stiffness, elastic bedding and soil shear effect matrices of a fully compatible ring sector plate element, developed by Saygun (1974), are obtained numerically assuming variable thickness of the element. Ring sector soil finite element is also defined to determine the deflection of the soil surface outside the domain of the plate in order to establish the interaction between the plate and the soil. According to Vallabhan and Das (1991) the elastic bedding (C) and shear parameters ($C_T$) of the foundation are expressed depending on the elastic constants ($E_s$, $V_s$) and the thickness of compressible soil layer ($H_s$) and they are calculated with a suitable iterative procedure. Using ring sector elements presented in this paper, permits the generalization of the loading and the boundary conditions of the soil outside the plate.

• Structural Engineering and Mechanics
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• v.29 no.3
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• pp.327-349
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• 2008

Some unreasonable results from the use of a popular thick plate element are discovered from the analysis of a raft foundation and a pile cap in Hong Kong. To overcome the problems, the authors have developed a new shear deformable beam which can be extended to a general quadrilateral shear deformable plate. The behaviour of this new element under several interesting cases is investigated, and it is demonstrated that the new element possesses very high accuracy under different depth/span ratios, and the results from this new element are good even for a coarse mesh.