• Structural Engineering and Mechanics
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• v.65 no.4
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• pp.369-380
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• 2018

In this paper, a multi-layered finite element model for laminated glass plates is introduced. A layer-wise theory is applied to the analysis of laminated glass due to the combination of stiff and soft layers; the independent layers are connected via Lagrange multipliers. The von $K{\acute{a}}rm{\acute{a}}n$ large deflection plate theory and the constant Poisson ratio for constitutive equations are assumed to capture the possible effects of geometric nonlinearity and the time/temperature-dependent response of the plastic foil. The linear viscoelastic behavior of a polymer foil is included by the generalized Maxwell model. The proposed layer-wise model was implemented into the MATLAB code and verified against detailed three-dimensional models in ADINA solver using different hexahedral finite elements. The effects of temperature, load duration, and creep/relaxation are demonstrated by examples.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.703-709
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• 2001

In this paper, we analyzed the laminated composite sandwich plate structure of truss core with changing values of the designing parameters. As a result, in designing parameters of that, the more height and thickness of the laminated composite plate's core, the more increase of natural frequency. In this type of structure, in the case of applying core of the laminated composite plate and antisymmetric stacking, natural frequency has high value and we calculated the optimum angle-ply making natural frequency maximum. Natural frequency of CFRP is higher than that of GFRP. Both are materials of the laminated composite plate. The mode shapes are various along with the angle-ply of the laminated composite plate.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.616-622
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• 2001

In this paper, we analyzed the laminated composite sandwich plate structure of honeycomb core with changing values of the designing parameters. As a result, in designing parameters of that, the more height and thickness of the laminated composite plate's core, the more increase of natural frequency. The laminated angle has the maximum value when the plate of honeycomb core is join to opposite direction. This paper shows that the natural frequency of CFRP is higher than that of GFRP, and also impact strength marks maximum value in case of antisymmetry than symmetry of core. Also it shows that the mode shapes are various along with the angle-ply of laminated composite plate.

• Coupled systems mechanics
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• v.12 no.6
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• pp.519-530
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• 2023

This paper presents a mathematical model suitable for the calculation of laminated glass, i.e. glass plates combined with an interlayer material. The model is based on a beam differential equation for each glass plate and a separate differential equation for the slip in the interlayer. In addition to slip, the model takes into account prestressing force in the interlayer. It is possible to combine the two contributions arbitrarily, which is important because the glass sheet fabrication process changes the stiffness of the interlayer in ways that are not easily predictable and could introduce prestressing of varying magnitude. The model is suitable for reformulation into an inverse procedure for calculation of the relevant parameters. Model consisting of a system of differential-algebraic equations, proved too stiff for cases with the thin interlayer. This novel approach covers the full range of possible stiffnesses of layered glass sheets, i.e., from zero to infinite stiffness of the interlayer. The comparison of numerical and experimental results contributes to the validation of the model.

• Advances in Computational Design
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• v.7 no.3
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• pp.173-188
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• 2022

In modern buildings, glass is considered a structurally unsafe material due to its brittleness and unpredictable failure behavior. The possible use of structural glass elements (i.e., floors, beams and columns) is generally prevented by its poor tensile strength and a frequent occurrence of brittle failures. In this study an innovative modelling based on an equivalent thickness concept of laminated glass beam reinforced with FRP (Fiber Reinforced Polymer) composite material and of glass plates punched is presented. In particular, the novel numerical modelling applied to an embedding Carbon FRP-rod in the interlayer of a laminated structural glass beam is considered in order to increase both its failure strength, together with its post-failure strength and ductility. The proposed equivalent modelling of different specimens enables us to carefully evaluate the effects of this reinforcement. Both the responses of the reinforced beam and un-reinforced one are evaluated, and the corresponding results are compared and discussed. A novel equivalent modelling for reinforced glass beams using FRP composites is presented for FEM analyses in modern material components and proved estimations of the expected performance are provided. Moreover, the new suggested numerical analysis is also applied to laminated glass plates with wide holes at both ends for the technological reasons necessary to connect a glass beam to a structure. Obtained results are compared with an integer specimen. Experimental considerations are reported.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.89-92
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• 2002

Traditionally unidirectional laminated composite which are characterized by high specific stiffness and strength were used for structural application. But theses composites are highly susceptible to impact damage because of lower transverse tensile strength. The main failure modes of laminated composite are fiber breakage, matrix cracking and delamination for low velocity impact. The modified failure criterions are implemented to predict these failure modes with finite element analysis. Failure behavior of the woven fabric laminated composite which is used in forehead part of subway to lighten weigh has been studied. The new failure criterions are in good agreement with experimental results and can predict the failure behavior of the woven fabric composite plate subjected to low velocity impact more accurately.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.282-289
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• 2014

After being laminated with a combination of glass fiber reinforced plastic and plywood, the GFRP laminated plate was densificated for 1 hour at $150^{\circ}C$ with pressure of $1.96N/mm^2$. A partial reinforced beam was produced by attaching the 5 GFRP laminated plates to the joint of glulam and the column. In addition, the column to beam joint was produced by using reinforced laminated wooden pin which was made of GFRP sheet and plywood, fiber glass reinforced cylindrical-LVL column. The joint was made of round log, glulam and drift pin as the reference specimen, and its moment resistance was evaluated. As a result, the strength performance of specimens with partial reinforced beams were 1.8 times stronger than the reference specimen on average. Furthermore, rupture was neither occurred on partial reinforced beam nor column. Toughness and stiffness of joints were also fine. The GFRP sheet reinforced laminated plate showed better reinforcement effect than GFRP textile reinforced one. GFRP sheet was inserted into each layer of laminate, and it showed good condition in rotation-angle and strength, therefore it is the most appropriate to reinforce the part of the beam.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.571-578
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• 2014

As a way of developing wooden joint development, a glass fiber reinforced wood plate was manufactured to replace a steel plate. Also, the fracture toughness was evaluated. Through application to a cantilever-type specimen made of a column and a beam, the moment resistance performance was evaluated. For the fracture toughness specimen of the wood plate, 12 types were manufactured by varying the combination of a main member (veneer and plywood) and reinforcement (glass fiber sheet and glass fiber cloth). The results of the fracture toughness test indicated that the 5% yield load of the specimen using plywood was 18% higher than that of the specimen using veneer, and that the specimen reinforced by inserting glass fiber sheets between testing materials (Type-3-PS) had the highest average 5% yield load 4841 N. Thus, a moment resistance strength test was performed by applying Type-3-PS to a column-beam joint. The results of the test indicated that compared to the specimen using a steel plate and a drift pin (Type-A), the maximum moment ratio of the specimen using a glass fiber reinforced wood plate (Type-3-PS) and a drift pin (Type-B) was 0.79; and that a rupture occurred in the wood plate due to high stiffness of the drift pin. The maximum moment ratio of the specimen using a glass fiber reinforced wood plate (Type-3-PS) and a glass fiber reinforced wooden laminated pin (Type-C) was 0.67, which showed low performance. However, unlike Type-A, a ductile fracture occurred on Type-C, and the load gradually decreased even after the maximum moment.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.258-265
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• 2014

By replacing the previous metal connector on the joints of timber structure, the GFRP reinforced laminated wooden pin was produced using a wooden material and Glass fiber reinforced plastic(GFRP) composite laminate. In addition, using the reinforced wooden pin, the tensile type shear strength test was conducted. Based on the result of the bending strength test of the reinforced laminated wooden pin according to the GFRP arrangement, a specimen(Type-A) with a single insertion of GFRP for each layer have shown the most favorable performance. Also, it was verified that densified specimen hot pressed for an hour at the temperature of $150^{\circ}C$ and with the oppression pressure $1.96N/mm^2$ have shown the improved performance of 1.57 times than the specimen without the densification. And in the bending strength test considering the load direction, edgewise have shown a higher performance of 3.51 times than the flatwise. A shear strength test was conducted using the Type-A reinforced laminated wooden pin which have shown a moderate performance on the test. Based on the test conducted by differentiating the type of the joint plate and the connector, compared to the specimen(Type-DS) applied with the drift pin and steel plate, the specimen( Type-WL) applied with the GFRP reinforced laminated wooden pin and GFRP reinforced wooden laminated plate have shown 1.12 times higher shear strength and also have shown an excellent toughness even after the maximum load.

• Structural Engineering and Mechanics
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• v.57 no.1
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• pp.105-126
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• 2016

In the present study, modelling and vibration control of axially moving laminated Carbon nanotubes/fiber/polymer composite (CNTFPC) plate under initial tension are investigated. Orthotropic visco-Pasternak foundation is developed to consider the influences of orthotropy angle, damping coefficient, normal and shear modulus. The governing equations of the laminated CNTFPC plates are derived based on new form of first-order shear deformation plate theory (FSDT) which is simpler than the conventional one due to reducing the number of unknowns and governing equations, and significantly, it does not require a shear correction factor. Halpin-Tsai model is utilized to evaluate the material properties of two-phase composite consist of uniformly distributed and randomly oriented CNTs through the epoxy resin matrix. Afterwards, the structural properties of CNT reinforced polymer matrix which is assumed as a new matrix and then reinforced with E-Glass fiber are calculated by fiber micromechanics approach. Employing Hamilton's principle, the equations of motion are obtained and solved by Hybrid analytical numerical method. Results indicate that the critical speed of moving laminated CNTFPC plate can be improved by adding appropriate values of CNTs. These findings can be used in design and manufacturing of marine vessels and aircrafts.