• Fibers and Polymers
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• v.5 no.4
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• pp.316-320
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• 2004

Waterproof fabrics are seamed and sealed by waterproof sealing tape to prevent water from penetrating through the stitch holes. As this process may change the mechanical properties of breathable waterproof fabric related to its deformation with human body, the changes in mechanical properties were investigated. In both of parallel and perpendicular directions, tensile characteristics were remarkably changed with seaming and sealing processes. The increase of LT and WT means that the clothing sealed by waterproofing tape may produce somewhat discomfort feeling. On the other hand, the bridge of the sewing thread seemed to be reinforced by waterproofing tape. Shear characteristics such as G, 2HG, and 2HG5 gradually increased with seaming and sealing processes in parallel direction. However, they decreased with sealing process in perpendicular direction because the seam line would work as an axis located at the center of the testing range.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.10a
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• pp.217-223
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• 1996

A structure's vibration characteristic is determined by modal property of the system. Through proper vibration analysis or experiments, the structure can be modified to reduce of vibration and noise. This paper is concerned with the natural frequency and modal loss factor of sandwich plates with viscoelastic core. The effects of shear and normal strain in the viscoelastic layer are investigated on modal properties, natural frequency and modal loss factor, by changing geometry parameter and viscoelastic material property of sandwich plates. The errors of modal parameters resulting from neglecting the extension or compression in the core material for simply supported(S-S-S-S) case are compared with those for clamped(C-C-C-C) boundary condition. Finite difference method(FDM) is utilized as numerical analysis technique of square sandwich plates for fixed boundary conditions. In order to reduce computation time and increase accuracy, improved finite difference expression with fourth order truncation error was used.

• Preventive Nutrition and Food Science
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• v.21 no.4
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• pp.367-372
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• 2016

To understand the effects of adding different gums (guar, xanthan, and locust bean gums) on naked barley flour (NBF), the rheological and pasting properties of NBF-gum mixtures were measured at different gum concentrations (0, 0.3, and 0.6% w/w). Steady shear rheological properties were determined by rheological parameters for power law and Casson models. All samples showed a clear trend of shear-thinning behavior (n=0.16~0.48) and had a non-Newtonian nature with yield stress. Consistency index, apparent viscosity, and yield stress values increased with an increase in gum concentration. Storage modulus values were more predominant than loss modulus values with all concentrations of gums. There is a more pronounced synergistic effect of elastic properties of NBF in the presence of xanthan gum. Rapid visco analyser pasting properties showed that the addition of gums resulted in a significant increase in the peak, breakdown, setback, and final viscosities, whereas the pasting temperature decreased.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.7
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• pp.1193-1202
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• 2001

The goal of this research is to investigate the effect of fusible interlinings on the mechanical characteristics and appearance related values for the Lyocell fabrics. In this study, to establish optimum fusing conditions, peel strength of the fused fabrics depending on the fusing temperature, pressure and time was measured. Appearance related properties and mechanical characteristics of the fused fabrics ere determined. The reulst are as follows: In the fusing condition of $120^{\circ}C,\;3kgf/textrm{cm}^2$, 15sec, peel strength was excellent. Peel strength was excellent in the case of tencel/cotton fabric, with increasing cover factor of woven interlining, with twill and nonwoven interlining. Flex stiffness was increased in the case of tencel/cotton fabric, with increasing weight of woven interlining, with twill and nonwoven interlining. Drapability was excellent in the case of 100% tencel fabric, with decreasing weight of woven interlining, with plain and woven interlining. Crease recovery was excellent in the case of 100% tencel fabric, with increasing weight of woven interlining, with twill and woven interlining. Shear and bend properties were increased in the case of tencel/cotton fabric, with increasing weight of woven interlining, with plain and nonwoven interlining.

• Geomechanics and Engineering
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• v.11 no.1
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• pp.161-175
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• 2016

A series of experimental studies are conducted on the deformation and shear strength property of compacted loess. The results reveal that the relationships of both the initial moisture content (w) and the initial degree of compaction (K) of compacted loess with cohesion (w) and the angle of internal friction (${\varphi}$) are linear. The relationship between the secant modulus ($E_{soi}$) and K is also linear. The relationship between $E_{soi}$ and w can be fitted well by a second-order polynomial. Further, when the influences of w and K are ignored, the relationship between the confined compression strain (${\varepsilon}$) and vertical pressure (p) can be expressed by a formula. A correction formula for the deformation of compacted loess caused by a change in w and K is derived on the basis of the study results.

• Carbon letters
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• v.17 no.1
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• pp.33-38
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• 2016

In the present study, exfoliated graphite nanoplatelets (xGnP) with different particle sizes were coated onto polyacrylonitrile-based carbon fibers by a direct coating method. The flexural properties, interlaminar shear strength, and the morphology of the xGnP-coated carbon fiber/phenolic matrix composites were investigated in terms of their longitudinal flexural strength and modulus, interlaminar shear strength, and by optical and scanning electron microscopic observations. The results were compared with a phenolic matrix composite counterpart prepared without xGnP. The flexural properties and interlaminar shear strength of the xGnP-coated carbon fiber/phenolic matrix composites were found to be higher than those of the uncoated composite. The flexural and interlaminar shear strengths were affected by the particle size of the xGnP, while the particle size had no significant effect on the flexural modulus. It seems that the interfacial contacts between the xGnP-coated carbon fibers and the phenolic matrix play a role in enhancing the flexural strength as well as the interlaminar shear strength of the composites.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1651-1656
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• 1995

The adhesively bonded tubular single lap joint shows large nonlinear behavior in the loaddisplacement relation, because structural adhesives for the joint are usually rubber toughened, which endows adhesives with nonlinear shear properties. since the majority of load transfer of the adhesively bonded tubular single lap joint is accomplished by the nonlinear behavior of the adhesive, its torque transmission capability should be calculated incorporating nonlinear shear properties. However, both the analytic and numerical analyses become complicated if the nonlinear shear properties of the adhesive are included during the calculation of torque transmission capabilities. In this paper, in order to obtain the torque transmission capabilities easily, an iterative solution which includes the nonlinear shear properties of the adhesive was derived using the analytic solution with the linear shear properties of the adhesive. Since the iterative solution can be obtained very fast due to its simplicity, it has been found that it can be used in the design of the adhesively bonded tubular single lap joint.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.78-91
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• 2024

Double steel plate concrete composite shear wall (SCSW) has been widely utilized in nuclear power plants and high-rise structures, and its shear connectors have a substantial impact on the seismic performance of SCSW. Therefore, in this study, the mechanical properties of SCSW with angle stiffening ribs as shear connections were parametrically examined for the reactor containment structure of nuclear power plants. The axial compression ratio of the SCSW, the spacing of the angle stiffening rib arrangement and the thickness of the angle stiffening rib steel plate were selected as the study parameters. Four finite element models were constructed by using the finite element program named ABAQUS to verify the experimental results of our team, and 13 finite element models were established to investigate the selected three parameters. Thus, the shear capacity, deformation capacity, ductility and energy dissipation capacity of SCSW were determined. The research results show that: compared with studs, using stiffened ribs as shear connectors can significantly enhance the mechanical properties of SCSW; When the axial compression ratio is 0.3-0.4, the seismic performance of SCSW can be maximized; with the lowering of stiffener gap, the shear bearing capacity is greatly enhanced, and when the gap is lowered to a specific distance, the shear bearing capacity has no major affect; in addition, increasing the thickness of stiffeners can significantly increase the shear capacity, ductility and energy dissipation capacity of SCSW. With the rise in the thickness of angle stiffening ribs, the improvement rate of each mechanical property index slows down. Finally, the shear bearing capacity calculation formula of SCSW with angle stiffening ribs as shear connectors is derived. The average error between the theoretical calculation formula and the finite element calculation results is 8% demonstrating that the theoretical formula is reliable. This study can provide reference for the design of SCSW.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1417-1421
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• 2008

Temperature variation affect the response of asphalt pavement and should be considered in the evaluation of performance of the pavement. In this paper, HWAW method is applied to evaluate shear wave velocity(or shear modulus) of the asphalt pavement with temperature. HWAW method which is based on time-frequency analysis using harmonic wavelet transform have been developed to determine phase and group velocities of waves. This method minimize effect of noise and is not affected by mode jump effect which cause erroneous result when surface wave method is applied to pavement evaluation. In order to estimate the applicability of HWAW method, field tests were performed in 1 site and preliminary correlation between shear wave velocity(shear modulus) and asphalt pavement average temperature.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.10
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• pp.58-64
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• 1998

Rubber isolator has many advantages compared with steel spring mount. Rubber has high internal damping and can be formed various shape depending on specific purpose. On the contrary, low modulus of elasticity of rubber results the instability of rubber isolator by buckling phenomenon. This paper presents the development of shear type rubber isolator for industrial application by using shear rigidity property of rubber. The static load-deflection characteristics of developed isolator has been analyzed by the FEM. Consequently, the static load testing and a measure of the effectiveness of a vibration isolator in terms of force transmissibility for developed isolator have been carried out.